Title Page
 Pineapple culture in Florida
 Fertilizers for pineapples

Title: Florida quarterly bulletin of the Department of Agriculture
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00077080/00050
 Material Information
Title: Florida quarterly bulletin of the Department of Agriculture
Series Title: Florida quarterly bulletin of the Department of Agriculture.
Uniform Title: Report of the Chemical Division
Alternate Title: Pineapple culture
Physical Description: 9 v. : ill. (some folded) ; 23 cm.
Language: English
Creator: Florida -- Dept. of Agriculture
Publisher: Department of Agriculture. State of Florida.
Place of Publication: Tallahassee, Fla.
Manufacturer: Artcraft Printers
Publication Date: July 1927
Frequency: quarterly
Subject: Agriculture -- Periodicals -- Florida   ( lcsh )
Agricultural industries -- Statistics -- Periodicals -- Florida   ( lcsh )
Genre: periodical   ( marcgt )
Periodicals   ( lcsh )
Statistics   ( lcsh )
Dates or Sequential Designation: Vol. 31, no. 4 (Oct., 1921)-v. 39, no. 3 (July 1929).
General Note: Title from cover.
General Note: Each no. has also a distinctive title.
General Note: Many issue number 1's are the Report of the Chemical Division
General Note: Issues occasional supplements.
 Record Information
Bibliographic ID: UF00077080
Volume ID: VID00050
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 28473180

Table of Contents
    Title Page
        Page 1
        Page 2
    Pineapple culture in Florida
        Page 3
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
        Page 12
        Page 13
        Page 14
        Page 15
        Page 16
        Page 17
        Page 18
        Page 19
        Page 20
        Page 21
        Page 22
        Page 23
        Page 24
        Page 25
    Fertilizers for pineapples
        Page 26
        Page 27
        Page 28
Full Text

---- ---e e-.-s----


Pineapple Culture

(Reprint from Farmers' Bulletin No. 1237,
U. S. Dept. of Agriculture)


Commissioner of Agriculture
Tallahassee, Florida

;R 3

Artcraft Printers, Tallahassee. Florida


This bulletin discusses the history of pineapple
growing in Florida, the usual methods of culture, the
causes for the recent decline of the industry, and
the most promising methods for its restoration.
This once thriving industry has rapidly declined
in recent years. Most of the fields have been aban-
doned and pineapple growing in Florida is now
threatened with extinction. The chief causes are the
depletion of soil humus and fertility through con-
stant cultivation and exposure to the tropical sun,
the growing prevalence of wilt due to attacks of
nematodes, and failure to use healthy, vigorous slips
in new plantings.
As a practical method of restoring abandoned
fields, it is recommended that Natal grass be sown
and allowed to grow on the impoverished soil for
two years or longer. This practically starves out the
nematodes, as Natal grass is immune, or nearly so,
to them, and at the same time adds the essential
humus to the soil. Carefully selected and vigorous
slips should then be planted. Whenever pineapples
begin to show a decrease in production the land
should again be rotated to Natal grass.
By the use of the methods suggested, which are
based upon experimental planting made by the
Bureau of Plant Industry, it is believed that pine-
apple growing eventually can be reestablished, not
only in Florida, but in other sections where similar
conditions exist.

Contribution from the Bureau of Plant Industry
WM. A. TAYLOR, Chief
Washington, D. C. Issued November, 1921

Pineapple Culture in Florida*

By E. D. VOSBURY, Formerly Scientific Assistant, Office of
Horticultural and Pomological Investigations, and J. R.
WINSTON, Pathologist, Office of Fruit-Disease Investiga-


The pineapple, universally considered one of the
finest of all fruits, is widely cultivated throughout
the tropical regions of the world. Large quantities
of the fresh fruit are annually imported into the
United States from the West Indies (including Porto
Rico), and from the Hawaiian Islands still larger
shipments of the canned article are received.
A native of tropical South America, the pineapple
is so easily injured by cold that its culture in the
United States is restricted to the regions of southern
Florida, most nearly frost free. Small plantings
have been started from time to time in California
and in southeastern Texas, but these have been
abandoned on account of adverse climatic or other


The earliest recorded successful planting of pine-
apples in Florida was made in 1860, when Benjamin
Baker, of Key West, obtained a number of slips from
Havana and started a small experimental patch on
Plantation Key. The venture was so successful and
the profits realized were so excellent that a rapid
The writers are indebted to C. D. Sherbakoff, pathologist, Florida
Agricultural Experiment Station; R. L. Goodwin, A. W. Hoofnagle, and
T. C. HeIllich, Fort 'ierce, Fla.; C. Dunscombe, Stuart, Fla.; T. V.
Moore, Miami, Fla.: and other pineapple growers and investigators for
valuable suggestions and assistance.

growth of the industry on the keys resulted. The
shallow soils of the keys soon became exhausted, and
most of the plantations there were abandoned. In
the meanwhile the industry had spread to other
parts of Florida where pineapple culture met with
varying success. A number of plantings under sheds
were made in Lake, Orange, Volusia, and other in-
terior counties, but with few exceptions these were
soon abandoned. By 1890 the industry had become
centralized in the famous east-coast pineapple belt,
extending from the vicinity of Fort Pierce southward
to Miami.
In spite of occasional setbacks from freezes and
other causes, the industry in the east-coast belt grew
and prospered, and by 1910 there were more than
5,000 acres of pineapples in that section.. For many
miles along the Indian River the pineapple fields ex-
tended in an almost unbroken expanse, and the an-
nual crop exceeded 1,000,000 crates. At about that
time, however, serious crop shortages began to occur
in some of the older plantings, where the plants com-
menced to show loss in vigor and decreasing yields.
This decline became more and more prevalent, until
by 1917 many of the fields had been permanently
abandoned or neglected. A heavy freeze which
swept over the State in February, 1917, and a second
freeze in the fall of that year were final blows to
many growers. In 1920 there were only a few hun-
dred acres of bearing pineapples in Florida. But
few new plantings had been made since the freeze of
1917, owing to the scarcity of slips and to the belief
of the growers that the suitable pineapple soils were
Near Punta Gorda, on the western coast of the
State, about 60 acres of pineapples were grown with
shed protection in 1915. Fruit of choice quality was
produced, and the industry there was considered
quite promising. As on the east coast, however,
these plantings have largely died out during the past
few years, and in 1920 only two or three acres re-
The failure of the pineapple industry of Florida is
a particularly serious matter to the farmers of these
localities, as much of the land on which this fruit has
been grown is too light and sandy for the profitable

production of other crops. The demand for reliable
information regarding the profitable restoration of
the abandoned fields is therefore urgent.



As pineapples are injured by temperatures lower
than 300 F., a locality for their culture should be
selected which is practically free from severe
freezes. Nearly all plantings in Florida have been
made in the southern portion of the State. It should
be understood, however, that though general cli-
matic conditions become more tropical as one pro-
ceeds southward, latitude alone does not determine
the danger from freezes. Damage from cold is often
greater in southern localities than in latitudes far-
ther north, and the topography and surroundings of
a locality influence its liability to freezes and its suit-
ability for tropical fruit culture. The effects of local
climatic conditions are illustrated in the leading
pineapple sections of Florida.
The earliest plantings were made on the coastal
islands, or keys, in the extreme southern part of the
State, which are surrounded and protected by large
bodies of salt water. The famous east coast pine-
apple belt consists of a narrow ridge, an ancient sand
dune, 1 to 3 miles wide and about 150 miles long,
which is elevated some 25 to 50 feet above the sur-
rounding country. It is bounded on the east by the
waters of the Indian River and the Atlantic Ocean
and on the west by marshes known locally as "savan-
nahs." The elevation of this ridge above the sur-
rounding country adds greatly to its freedom from
frost, as the cold air drains to the lower levels. The
large bodies of water on either side of the ridge also
furnish further protection from cold.

After a favorable general locality has been de-
cided on, consideration should be given to the selec-
tion of a desirable site within that region. The

choice must be made with great care, as very fre-
quently desirable and unsuitable sites are found in
close proximity. Careful consideration should be
given to the question of local air drainage and water
protection and their influence on potential damage
from cold. The factor of roads should also be taken
into account, as pineapples are injured by long hauls
over rough roads, and, besides, such hauls are ex-
pensive. A field should be selected, therefore, as
near as possible to a good shipping point. Among
other points which should be considered in selecting
a site are community advantages, an adequate sup-
ply of labor, and marketing facilities.
Many of the conditions for successful pineapple
growing will be unfamiliar to growers who may have
been successful with other fruits. The mistake of
choosing an unsuitable site for a pineapple planta-
tion, as in the case of other kinds of fruit growing.
is likely to prove extremely costly and is usually
without remedy. The newcomer, especially when
his capital is limited, should proceed with great
caution and purchase land only after thorough in-
vestigation and after consultation with successful


Pineapples require an open, thoroughly drained
soil. Nearly all of the Florida plantings have been
made on light sandy soils, too low in fertility for
most crops but adapted for pineapples when prop-
erly fertilized and supplied with humus. The main-
tenance of a sufficient supply of humus in pineapple
growing, as in the culture of other crops, is essential
in order to increase the beneficial activity of soil
organisms, to promote the general fertility of the
soil, and to improve its physical condition. Most
Florida pineapple soils in their original state are
poorly supplied with humus, and one of the essential
measures that must be taken in building up the Flor-
ida pineapple industry, as will be shown later in
considering humus depletion, is that of maintaining
and increasing the humus supply.
Most of the fields of the east coast belt have been
planted on scrub-pine land which bears an original

growth of scrub-pine trees. The soil of this type is
a white sand underlain at a depth of 5 feet or more
with a subsoil of yellow sand. A somewhat more
limited soil type is that known as "hickory scrub,"
which supports a native growth of hickories, oaks
and other hardwood trees. It is underlain at a depth
of 5 to 10 inches with the same yellow sand subsoil
found at a much greater depth in the scrub-pine
land. The soil of the "hickory scrub" land is some-
what finer in texture, richer in humus, and more re-
tentive of fertility than the scrub-pine land. It is
the soil type preferred by most experienced Florida
growers. The hammock type of land in a virgin
state is characterized by a growth of cabbage pal-
mettos and live oaks. This type is the richest in fer-
tility and humus of any of the soils commonly used
for pineapples. It is also well adapted for vegetables
and other crops, but is only found in small tracts in
the pineapple growing sections. The high pineland
is considered satisfactory for pineapples, but is found
only to a very limited extent in Florida regions where
climatic conditions permit the growing of pineapples
in the open. Flatwoods pineland, found particularly
in the vicinity of Miami and Punta Gorda, is also
satisfactory when provided with natural or artificial


A large number of pineapple varieties have been
introduced into Florida from time to time, many of
them being still found in home gardens and experi-
mental plantings. Only two or three varieties are
grown on a commercial scale.
The Spanish (Red Spanish) variety, spoken of as
the "common pineapple," is by far the most widely
cultivated, constituting more than 90 per cent of the
total plantings. The.plants are hardier than those
of the other common varieties and easier to grow.
They are easily propagated from slips, which are
abundantly produced. The fruits of this variety are
of medium size and possess excellent shipping qual-
ity when carefully handled, but their dessert qual-
ity, while good, is inferior to that of other varieties

The only other pineapple variety grown in Florida
to any important extent is the Cayenne (Smooth
Cayenne). The plants of this variety are large, with
broad leaves, free from spines. The fruits are larger
and have higher dessert quality, but are more ten-
der, more easily injured, and require much more care
in handling and shipping than those of the Spanish
variety. The Cayenne is propagated chiefly from
suckers, as few slips are produced. The scarcity of
slips is a serious drawback when rapid propagation
is desired, as but one or two suckers can be taken
from a plant. The Cayenne is the principal variety
canned in Hawaii.
The Abachi (Abakka) variety is grown to a very
limited extent in one or two localities. The fruits
are of large size and of excellent dessert quality,
but they are tender and must be carefully handled
in harvesting and shipping.
A serious fault of the Abachi variety is that the
slips are often attached so closely to the base of the
fruit that it is difficult to separate them without in-
jury to the fruit.
For the average grower in Florida the hardy and
easily grown Spanish is probably the best variety to
plant. The grower who desires to develop a special
market for fancy fruit and who is prepared to give
his crop the most skillful and painstaking attention
will usually prefer the Cayenne or the Abachi va-



After fruiting, the central portion of the plant
gradually dies back toward the base. Before the
fruit is mature, however, suckers begin to develop
in the axils of the leaves above ground, and other
suckers, called ratoons, also develop from points
along the stem below the surface of the ground.
These ratoons take root directly in the soil, while
the suckers which develop from the axils of the
leaves are nourished first through the base of the
parent plant and later by aerial root systems which
eventually take root in the ground. The plant

growths from buds on the fruit stalk near the base
of the fruit are known as "slips," while the tuftlike
growth at the top of the fruit is called a "crown."
Slips appearing at the apex of the fruit just below
the crown are called "crown slips."
The pineapple occasionally produces seeds. These,
however, do not reproduce the variety. They are
rarely used, except for experimental purposes. Sev-
eral years are required to produce a mature plant
from a seed.
Propagation is usually accomplished by means of
slips or suckers, although crowns and other vegeta-
tive parts of the plants are sometimes used. The
Spanish variety is commonly propagated from slips,
which are produced at the average rate of five or
six to the plant. The Cayenne variety produces an
average of less than one to the plant and is common-
ly propagated both from slips and suckers. The
Abachi variety is usually propagated by means of
slips, which are abundantly produced.
The ratoons are generally left in place to perpet-
uate the plantation. As they develop they take the
place of the former fruit-bearing stalk. The suckers,
unless removed, normally take root and also form
new fruiting plants. After they have produced fruit
they in turn give way to other ratoons or basal suck-
ers. The number of ratoons a plant may develop
varies, as does the number of slips and suckers. Two
ratoons to each plant are desirable for perpetuating
a plantation. If surplus ratoons develop they may
be removed and used, as are slips and suckers, for
other plantings.


The same methods are used in the collection and
preparation of both suckers and slips. Although
planting may be successful at any season, it is usually
done in August and September. Most growers pre-
fer to set their slips before the middle of September,
in order to secure advantages of the summer rainy
season. From eight to twelve thousand suckers or
slips are required to plant an acre.
Suckers and slips are removed from the parent
plant after they reach full maturity, which is indi-

cated by the brown color of the stem of the sucker or
slip. In collecting these, laborers proceed through
the fields, break them off and throw them into the
aisles, to be collected into piles. The material is
then trimmed by cutting off the hard basal end and
stripping off the lower leaves, a process which some-
times facilitates its rooting when planted in dry soils.
Some growers cure their suckers and slips by expos-
ing them to the sun for a week or two before plant-
ing, but while this process is supposed to make the
plants more disease resistant, there is little evidence
to show that any benefit is derived thereby.
Planting may be done at any time within two or
three weeks after the suckers or slips are gathered.
Slips are usually set 2 to 4 inches deep and suckers
from 3 to 5 inches deep, according to size. In set-
ting, a small hole is made in the soil with the fingers
or with a dibble, a slip is inserted, and the soil then
firmed about it so that the bud is about one inch
above the surface of the ground.


In gathering suckers or slips for planting, few
growers pay any attention to the quality or condi-
tion of the parent plant or to the desirability of the
fruit which it bears. All suckers and slips of con-
venient size for planting usually are collected, and
when they are scarce even the smallest and scrub-
biest, including those from weak or diseased plants
or from plants bearing small, misshapen fruits, are
gathered and planted. As a result of this indiscrim-
inate planting, many undesirable types of plants and
fruits are perpetuated. Moreover, it is probable that
communicable diseases are frequently transmitted
from unhealthy parent plants to new fields.
Trial plantings made by the Bureau of Plant In-
dustry of the United States Department of Agricul-
ture and investigations made throughout the Florida
pineapple sections have shown emphatically that
more care in selecting propagating material is essen-
tial. It has been found that large slips and suckers
selected from healthy, vigorous plants not only pro-
duce much stronger plants but they are more free
from disease. Furthermore, they come into bearing

from 12 to 24 months sooner than weak or diseased
plants. Suckers and slips selected from poor plants
start to grow very slowly and rarely become strong
plants or produce profitable crops. In every case
observed the best results were obtained where ma-
terial was selected with the greatest care from the
strongest, healthiest and most productive parent
plants. The reputed superiority of Cuban grown
slips is due solely to the fact that they are larger
and have usually been taken from strong, vigorous
plants. Home-grown slips give similar results when
selected from equally desirable plants.
In order to insure the selection of suckers and slips
from the best plants, the finest and healthiest parent
plants should be marked at fruiting time, when their
inherent characteristics are most apparent. They
may be marked by means of stakes, by splashing a
little whitewash on one or two of the most prominent
leaves, or by other convenient methods. When the
propagating materials are collected the plantation
owner should make sure, by careful supervision, that
only these selected materials are taken. When
parent plants have not been marked at fruiting time
or when an insufficient number have been so marked,
special care should be taken to see that slips are col-
lected from the healthiest and most vigorous plants
in the field.
There is no longer any doubt that the proper selec-
tion of the best parent plants, long recognized as
most important with other crops, is just as essential
to the best results in pineapple growing. By careful
selection of suckers and slips, the size and quality of
pineapples can be greatly improved. Many of the
failures in the past have been due in large measure
to the careless selection of slips, especially to the use
of slips from weak or undersized plants.


When virgin land is to be planted, the timber
growth usually is grubbed off, although pine stumps,
which quickly decay, are sometimes left in place.
After grubbing, the brush and roots are burned;

however, this should not be done on the land to be
planted, as fire destroys much of the valuable humus
of the soil. After the land has been deeply plowed
and leveled it is ready for marking off.


The fields are laid off for planting with a plow or
a marker similar to that used in planting corn. In
the commonly used wide-bed system, plants are usu-
ally spaced 22 inches apart in rows which are also
22 inches apart. Six rows constitute a bed, and every
seventh row is skipped and left as an aisle between
two beds. Two rows are omitted after every third
bed for a roadway. Approximately 10,000 slips are
required to plant one acre with this spacing.
In the Cuban planting system occasionally fol-
lowed, plants are set 10 inches apart in double rows,
which are 12 inches apart, with 6 feet separating the
pairs of rows. This system saves hand labor by per-
mitting cultivation with horse-drawn implements
during the first two years after planting; further, the
fruit produced averages somewhat larger than where
the wide-bed system is used. The losses from sun-
burned fruit are much greater, however, as the plants
shade each other less than in the wide-bed system.
The depletion of humus due to exposure to the sun
is another disadvantage of the Cuban system.


A few days after planting, a tablespoonful of cot-
tonseed meal is dropped into the bud of the slip.
This practice, known as "budding," results in the
formation of a hard core, which prevents sand from
blowing in and smothering the bud.
The general care of the pineapple field is com-
paratively simple, consisting mainly of three or four
annual cultivations with the scuffle hoe to keep down
the weeds. Care should be taken during hoeing and
other cultural operations to avoid breaking the brit-
tle pineapple leaves, as when these are injured they
lose moisture to such an extent that the plant may
be seriously damaged.


Most Florida pineapple soils are very low in fer-
tility and require heavy applications of fertilizers as
well as the addition of humus for the production of
profitable crops. Many systems of fertilization are
used successfully. The Florida Agricultural Experi-
ment Station recommends for the average soils of
the east coast pineapple belt from 3,500 to 4,000
pounds to the acre annually of commercial fertilizer
analyzing 5 per cent nitrogen, 4 per cent available
phosphoric acid, and 10 per cent potash, applied in
four applications a year for the first 18 months after
the field is planted.
It is further recommended that after this a similar
yearly amount be given in two applications, namely,
in February, and in July after harvest. Nitrate of
soda may be used during the first six months after
planting, but after that time organic forms of nitro-
gen, such as tankage, cottonseed meal and dried
blood give the best results. Finely ground steamed
bone is recommended as preferable to acid phos-
phate as a source of phosphorus and sulphate of
potash as preferable to muriate of potash.
The fertilizing methods used by successful grow-
ers vary greatly and there is very little agreement as
to what constitutes the best practice. A number of
successful growers apply a ton of tankage to the acre
in July after the main crop is harvested and add a
light dressing of tobacco stems in the fall or in early
spring. Other leading growers have obtained ex-
cellent results from an application of about 1,500
pounds of standard commercial "pineapple ferti-
lizer" in February, followed by a second similar ap-
plication after harvest and a third application of
1,000 to 1,200 pounds of tobacco stems in early
winter. A beginner in pineapple growing should
follow the methods found most successful by ex-
perienced growers in his immediate vicinity. At the
same time he should carefully experiment with dif-
ferent combinations of fertilizers, in order to deter-
mine the best method of fertilizing for his own par-
ticular conditions.


For growing pineapples in sections too cold for
culture in open fields and also where the protection
of fancy tender varieties is desired, protecting sheds
are often used. All of the plants in the vicinity of
Punta Gorda, where the choice, tender Cayenne va-
riety is grown, as well as most of the few plantings
in the central counties are provided with shed pro-
tection. In addition to furnishing to the plants
marked protection from the cold, these sheds pre-
vent excessive evaporation from the soil and the
foliage of the plants, thus conserving the moisture.
When grown under sheds the plants are usually more
vigorous and productive and the fruit is larger, bet-
ter in dessert and shipping quality, and freer from
sunburn than if the plants were grown in the open.
For these reasons sheds are sometimes used in re-
gions comparatively free from frosts.
The methods of constructing sheds vary with the
material available. The sheds are usually made 6
to 7 feet high to allow perfect freedom in working
under them. A plan of construction frequently used
is to set pine posts firmly in the ground about 9 by
14 feet apart, with stringers of 1 by 8 inch material
attached to the top of these posts running the 14-foot
way. A narrower strip placed below the main
stringers is nailed to the posts, running the 9-foot
way, to give additional firmness. The roof is made
of common building lath or of 1 by 3 inch pine
boards 18 feet long nailed to the stringers, leaving
a 3-inch space between boards. It is a generally
recognized principle that regardless of other details
of construction the best results are obtained when
about one-half shade is provided.
In the colder localities of Florida where pineapples
are grown, sheds are usually provided with side walls
of cloth or boards, used for additional protection
during severe freezes.
The cost of construction of pineapple sheds in
1918 averaged in the neighborhood of $800 an acre,
and the additional expense for upkeep was about
$75. While plants grown under sheds are more vig-
orous than those grown in the open, they are not free
from disease, and in view of the increasing difficulty

in securing profitable yields under any condition few
growers feel justified in making the large investment
required for shed construction and upkeep. The use
of sheds in the future will probably be largely con-
fined to the production of fancy, high-priced vari-
eties, which are most likely to repay the extra invest-
ment and care involved.


Although some fruits ripen and are shipped at
all seasons of the year, the main harvest season for
Florida pineapples extends from late May to mid-
July. In harvesting, laborers protected from the
sharp spines of the plants by heavy canvas gloves
and leggins, proceed through the fields, break the
fruits from the plants, and toss them to other labor-
ers stationed in the aisles between the beds, who
carefully catch the fruits and deposit them in the
field crates. The fruit is then hauled to the packing
house by wheelbarrow, wagon or motor truck, where
it is in turn sized, graded, wrapped in tissue paper,
and packed in crates holding 18 to 56 pineapples,
depending upon the size of the fruit. The unique
methods of harvesting and gathering pineapples and
the great activity during the height of the shipping
season furnish a most interesting and picturesque


Investigations of the Bureau of Plant Industry of
the United States Department of Agriculture con-
ducted in Florida, and other investigations made in
the West Indies, have demonstrated that greater
care should be used in all the operations of harvest-
ing, packing and shipping the fruit, in order to pre-
vent punctures and bruises, which are the chief
sources of decay. It has been shown that fruit should
be shipped as promptly as possible after picking, as
its keeping quality is greatly impaired by delay
either in the field or packing house, especially when
the weather is warm; also that fruit should be

packed only when it is dry, as decay is greatly
favored by the presence of moisture. Neglect to
handle the fruit carefully and ship it promptly often
results in very heavy losses, the pineapples arriving
at the northern markets in an almost unsalable con-
dition on account of extreme decay.


For shipping to distant markets, pineapples are
usually picked and packed while still hard and
green. While this green fruit becomes yellow and
edible before it reaches the consumer, it is never
equal in sweetness or flavor to fruit which has been
permitted to ripen on the plant. The reputation
made by the canned pineapples imported from Ha-
waii is largely due to the fact that this fruit is picked
only when fully matured.
Experiments of the Bureau of Plant Industry ot
the United States Department of Agriculture have
shown that the superior plant-ripened fruit, if picked
at the proper stage of maturity, carefully handled,
and promptly shipped in iced cars, may be sent to
northern markets with very little decay.
The best stage of maturity for picking plant-
ripened fruit was found to be the hard-ripe or
"ruddy-ripe" stage, when the pineapple has turned
to a reddish yellow but before it becomes fully yel-
low or soft. At this stage of maturity the fruit has
reached the acme of dessert quality, but is still firm
enough to permit shipping for long distances if prop-
erly handled.
This method of shipping plant-ripened fruit has
many possibilities and is considered of special prom-
ise for growers who raise the choice varieties for the
fancy-market trade.
When green fruit is shipped in the ordinary way
and allowed to ripen en route to market, only fully
grown pineapples with well-developed eyes having
a trace of light green showing between them should
be picked. Purplish green fruit and fruit with par-
tially developed or shrunken eyes should be left on
the plants until they have reached the condition de-
scribed above.
Immature fruit is low in table quality and ships

and keeps poorly. Overripe, soft or defective fruit
should be excluded from the general pack, and
canned, sold on the local market, or otherwise used.
The question of proper maturity for picking as well
as the factors involved in the careful handling of
fruit to prevent decay demands closer attention from
pineapple growers than has usually been given.
Further information relative to methods of shipping
and handling pineapples may be obtained by ad-
dressing the United States Department of Agricul-


When vigorous, healthy, carefully selected slips
have been planted under favorable conditions, the
first crop of pineapples is harvested about 20 months
after planting, and annual crops are secured there-
after during the life of the plantation. Yields vary
greatly, depending upon the skill of the grower, the
season, and other factors. A yield of 200 crates to
the acre was formerly considered a good average,
although some growers secured 300 crates or more.
Prices have fluctuated greatly, but in average seasons
have been quite satisfactory, and frequently addi-
tional receipts are obtained from the sale of slips.
Taken as a whole, the pineapple industry up to about
1917 was profitable and yielded satisfactory returns.
At the present time (1920) prices for pineapples are
higher than ever before, but, for the reasons men-
tioned, production and profits in most fields have
reached the vanishing point.


The period during which pineapple fields bear
pofitable crops varies with the site, soil, care and
other factors.
Plantings made in the earlier days of the industry
on virgin soil, comparatively free from disease, occa-
sionally bore profitably for 10 years or even longer,
although in most cases production declined so rap-
idly after the fifth year that further maintenance
was unprofitable. In more recent years the deple-
tion of soil humus and the increasing prevalence of

disease have greatly shortened the productive life
of plantations. Most fields set out since 1915 were
abandoned after the second or third year and many
were given up before a single paying crop was se-
cured. The condition of the industry has grown
steadily worse, and the severe freeze of February,
1917, so greatly damaged the already weak and dis-
eased plants that most of the fields have been aban-
doned altogether. Many attempts have been made
to clear and replant these abandoned fields, but
while replanting was often successfully accomplished
in the earlier years of the industry, most of the at-
tempts in recent years have been complete failures.
Many reasons have been advanced to explain the
decline of the industry, including inferior fertilizers,
particularly unfavorable seasons of weather, high
freight rates, labor costs, and other causes. The
chief reasons, however, are now determined to be
the depletion of soil humus, the prevalence of wilt.
and the scarcity of desirable slips.
In replanting, old plants are usually grubbed out
and burned. A number of growers have spaded
them into the ground at considerable cost, with the
idea of adding humus to the soil. However, new
plantings made where the old diseased ones have
been spaded in, though starting to grow vigorously,
have in nearly every case died out on account of wilt
after the first or second year. The practice of spad-
ing under the old plants and resetting immediately
does not seem, therefore, to be advisable. Better re-
sults have been obtained by plowing rotted leaves
and litter from woodlands into the soil. The most
desirable measures to be taken before replanting are
those described in connection with the discussion on
the restoration of the pineapple industry.



Among the several pests found in Florida pine-
apple fields are the red spider, which attacks the
basal part of the leaves, and the mealy bug, which
feeds on the buds and the leaves. Both of these pests

are common, but they seldom inflict severe damage.
Usually their attacks can be diminished by dropping
a handful of tobacco dust into the bud of the plant.

The soft, dark, fermented, decayed condition of
the fruit, frequently associated with heavy loss in
pineapple shipments and commonly called soft-rot,
is caused by the attacks of a fungus (Thielaviopsis
paradoxa), which enters the fruit through bruises,
punctures, and through the cut stem end. While
decay due to this fungus is seldom great in the fields,
it is sometimes so severe among pineapples in transit
to market as to cause almost a total loss of the ship-
ment. This loss is particularly liable to occur in
warm, humid weather, especially when the fruit has
been roughly handled, packed while wet, or delayed
before shipment, the decay spreading rapidly from
one affected fruit to other fruits in the same package.
Pineapples that have been packed when mature,
carefully handled, graded and properly shipped are
seldom seriously affected.
"Spike" or "long-leaf," a condition characterized
by long, spindling or spiky leaves, most frequently
occurs among pineapples grown on shell lands or
other soils high in carbonate of lime, and these soils
should be avoided in selecting a site for a plantation.
There is some evidence that in a number of cases
heavy applications of commercial fertilizers, particu-
larly muriate of potash, inorganic forms of nitrogen
(commonly referred to in terms of ammonia), and
acid phosphate have been followed by the appear-
ance of "spike."

The most widespread and destructive disease of
pineapples in Florida is red wilt, also called wilt, or
blight. It has been a chief cause of the decline of
the industry in that State.
Plants affected with wilt gradually lose their nor-
mal healthy green color and assume a dull reddish
hue. Usually the lower leaves are first affected,
but the entire plant eventually becomes red and limp
and finally droops and dies. The disease commonly

appears first in a few individual plants or groups of
plants scattered here and there about the field, but
it gradually spreads through the entire planting.
The affected plants sometimes survive the attacks
for months, especially when the weather and other
growing conditions are favorable, but in most cases
they die rapidly after the first symptoms of disease
appear. The roots are found to be rotted to a con-
siderable extent, even in early stages of the disease.

Although many theories have been advanced in
explanation of the causes of red wilt, recent investi-
gations indicate that it is a diseased condition of the
plant, due, at least in large measure, to the attacks
of nematodes (Heterodera radicicola), minute para-
sitic ground worms which infest most of the light
soils of the South and which are present in countless
numbers in most of the Florida pineapple fields.
These nematodes attack the pineapple plant by
penetrating and destroying its fine feeding roots,
thus gradually depriving the plant of its means of
taking up food and water, until, when all the feeding
roots are killed, the plant dies. The root galls caused
by the initiation of the nematodes are less conspicu-
ous on pineapples than on other hosts of this pest,
and the infested roots have a tendency to decay rap-
idly. A plant infested with nematodes has much the
same appearance as if it were suffering from drought
or lack of fertilizer, and this fact has resulted in
much of the confusion regarding the real cause of
the trouble. The wilting of pineapples in ways more
or less similar to those characteristics of the Florida
red wilt has been described from various parts of the
world. It is possible that some of the diseases so
described may have the same cause as the Florida
red wilt.
Nematodes are readily carried from infested land
to new soils on the feet of men or animals, on tillage
implements, and in many other ways. Red wilt is
usually first seen among pineapple plants adjacent
to roadways, where they would be most liable to in-
festation in this way. Moreover, when pineapples
are planted on cleared land adjacent to diseased

fields the wilt first appears on those plants which are
nearest to the old infested area. Slips from fields
infested with wilt may possibly carry nematodes to
new fields by coming in contact with infested soils.
Many native weeds are hosts for the nematodes, and
virgin land is not always entirely free from the pest.
The infestation in abandoned fields is maintained
on many of the weeds springing up naturally. The
spread of wilt is often very rapid, pineapple plants
on new fields usually showing symptoms within a
year or two after the land has been planted. The
spread often follows natural drainage slopes by the
washing of infested soil.

Many methods of combating red wilt have been
tried, but these have been generally unsuccessful,
owing to the lack of understanding of the real nature
of the disease. Slips have been brought from Cuba
and other distant points in the expectation that they
would prove free from disease. There is no evidence
to show that the imported slips are in any way more
desirable than equally healthy, vigorous, home-
grown slips. Besides, there is always the chance of
introducing some unsuspected pest on plant material
from outside sources. While the planting of good
slips is of the utmost importance, not even the best
of them can be expected to survive on soil depleted
of fertility or infected with disease.
Another control measure which has been tried is
that of spading calcium cyanamid into the soil at the
rate of one ton or more to the acre. The method has
given some measure of success, but it is too expen-
sive for general application.
All varieties of pineapples grown in Florida are
attacked by the nematodes. The Spanish is less sus-
ceptible, however, than the Cayenne. Investigations
made by the Bureau of Plant Industry of the United
States Department of Agriculture with the object of
selecting resistant strains or varieties may eventually
prove successful, but at the present time the only
promising plan of controlling wilt is that of first free-
ing the soil of nematodes, as discussed under the
heading "Restoration of the pineapple industry."


Red wilt due to the attack of nematodes is closely
associated with an equally important cause of the
decline of the pineapple industry, namely, the de-
pletion of the humus or decaying vegetable matter
in the soil. The destruction of humus through con-
stant cultivation and the exposure of the light sandy
soil to the tropical sun proceeds at a very rapid rate.
Even in their virgin state Florida pineapple soils are
poor in humus, and after a few years of intensive
cultivation this scanty supply is almost exhausted,
and the soil is left in an unproductive state, low in
fertility, and lacking in soil organisms essential to
healthy plant life. In such impoverished soils pine-
apples can not be expected to grow satisfactorily.
even if no disease is present to further impair the
vitality of the plants.
Pineapple culture on the keys and in other Florida
sections was abandoned when the vegetable matter
of the soils of the region became exhausted, and
fields which have been long under cultivation or ex-
posed to the sun for any length of time can seldom
be successfully replanted. It is clear, therefore, that
in restoring abandoned pineapple fields the replen-
ishment of the diminished humus supply must be
given full consideration.


The chief problem which must be solved before
pineapples can be replanted in Florida is the reduc-
tion of the number of nematodes and the restoration
of the depleted soil humus. Fortunately the remedial
measures most promising in controlling nematodes
are also most successful for replenishing soil fertility
and humus.
A number of the crops, particularly Natal grass,
velvet beans, and the Iron or other nematode-resist-
ant varieties of cowpeas, which can be grown even in
the light soils of the old pineapple fields, are nearly
or quite immune from attacks by nematodes. By
growing these crops for a period of several years the
pests can be starved out, and at the same time the
fertility of the soil can be built up to a degree favor-

able to the growth of pineapples. Preliminary re-
sults from experimental plantings made by investi-
gators of the Bureau of Plant Industry have shown
that of these crops Natal grass (Tricholaena rosea
Nees) makes by far the quickest and heaviest
growth, and of all crops tried it is the most satis-
factory and cheapest to plant. After land had been
sown and allowed to remain in Natal grass for two
years or more it was found that the nematodes had
practically disappeared and that, moreover, the soil
had become darker in color and rich in humus and
fertility. Healthy, vigorous slips recently planted on
this restored land have given every promise of high
future production. Plants growing vigorously under
such favorable soil conditions suffer less from cold
injury than less vigorous plants. They are able
readily to replace roots that may be destroyed by
nematodes and so can withstand moderate attacks of
this pest.

In conformity with the results thus far obtained
in these experimental plantings, it is suggested that
owners of land formerly planted to pineapples who
desire to put it in good shape for replanting proceed
in the following manner: The old plants that re-
main should be first gathered and then removed or
left to rot on the land. Natal grass seed should be
sown broadcast at the rate of 8 or 10 pounds per
acre. This can be done at any time of the year when
the soil moisture is sufficient for germination, but
preferably in the fall. Under ordinary conditions
this grass will quickly make a good start and should
be left undisturbed and allowed to reseed itself at
will. It will probably be effective to allow the land
to remain in Natal grass for two years, but if the soil
is in a very impoverished condition or badly infested
with nematodes, three years or longer may be
Before the Natal grass is turned under, tests
should be made to determine whether or not the
nematodes have been starved out. A few pepper
plants may be set in spots here and there through

the field. If these grow vigorously, with roots free
from the nematode galls, it may be assumed that the
nematodes are practically eliminated, because pep-
pers are very susceptible to attack by this pest and
would be affected where nematodes are abundant.
After tests made in this way indicate that the nema-
todes have been sufficiently reduced or eliminated,
the Natal grass can be plowed under and pineapples
In replanting, the most vigorous and healthy slips
should be selected. The fields should then be given
good care and every effort made to increase the vigor
and consequently the disease resistance of the plants
and to reduce the chances of nematode infestation
from near-by infected fields. The soil, however, is
likely to become reinfested sooner or later, often by
the time three or four crops have been harvested.
When the replanted fields begin to show decreased
yields as a result of reinfestation, the land should be
resown with Natal grass seed and that grass grown
until the humus is restored and the nematodes
starved out. In following this plan of restoration it
will be necessary for the pineapple grower to have
one-third to one-half of his acreage in Natal grass.
The added fertility secured in plowing under the
Natal grass should fully cover the expense involved
in carrying out the plan of rotation.
Many other methods of restoring pineapple fields
have been attempted, but without success. It seems
certain that no plan which neglects either nematode
control or humus restoration can be successful. On
the other hand, a number of growers who have put
into practice the plan suggested above are now se-
curing promising results and are producing crops on
a profitable basis. The building up of abandoned
pineapple soil with Natal grass in the manner sug-
gested promises to be a slow but sure method of re-
viving the pineapple industry not only in Florida but
in other sections where similar conditions exist.


A small portion of the abandoned pineapple land,
particularly that of the hammock type, is richer than
the average in fertility and is well suited for the cul-

ture of vegetables and fruits, such as limes, grape-
fruit and avocados. Many growers who formerly
raised pineapples exclusively are planting these
richer soils to some of these crops. Diversification
of this sort is safer and in the end probably more
profitable than specialization with a single crop, and
it should be encouraged. However, as the acreage
of land suitable for these other crops is limited, the
future prosperity of the farmers of the pineapple
section depends largely upon the restoration of the
pineapple industry.
Persons contemplating going into pineapple grow-
ing should thoroughly investigate conditions at first
hand before making any investment. This precau-
tion should be taken not only by prospective pine-
apple growers, but also by anyone planning to grow
fruit crops in Florida or any other part of the coun-
try. The rewards of fruit growing are often excel-
lent, but success requires careful preliminary inves-
tigation, considerable skill, and hard work, particu-
larly where the capital is limited. Pineapple grow-
ing is no exception to the rule. The new grower in
Florida should consult with the agricultural investi-
gators of the State and Federal governments, and
especially with successful and established growers.
These men are familiar with the ups and downs of
pineapple growing, and it is due to their determined
efforts for the restoration of the industry that the
future of pineapple growing now appears encour-
aging provided proper restoration methods are



The present indications are that the pineapple is
coming back and will again be a profitable crop for
farmers in certain sections of Florida. Pineapple
culture is confined most largely to a narrow strip of
land along the east coast of Florida, although there
are some fields at Punta Gorda and at Fort Myers.
Larger or smaller plantations also occur in some of
the islands and keys off the coast.


All of the materials available for experimentation
in the way of fertilizers for pineapples have been
used by the Experiment Station and some very val-
uable data on the subject has been secured.
Ammonia.-Of the ammoniates used, their order
of usefulness seems to range about as follows: dried
blood, blood and bone, cottonseed meal, castor pom-
ace. All of these organic materials are quite accept-
able to the pineapple plant. Where large quantities
of cottonseed meal was used, it produced "spike" in
the plants.
Nitrate of soda may be successfully used as a
source of ammonia while the plants are young and
there is little danger of getting the material in the
axils of the leaves. It is quite caustic to the foliage
and consequently somewhat difficult to apply.
Sulphate of ammonia should not be used, as this
gave uniformly detrimental effects.
Potash.-The magnesium potassium carbonate
gave best results in the form of potash. This form
of potash, however, has been withdrawn from the
market and is not recommended now.
The low grade sulphate of potash, or what is some-
times called double manure salts, also known as

August 18, 1920

potassium magnesium sulphate, gave almost as good
results as the potassium magnesium sulphate. High
grade sulphate of potash gave almost as good results
as the low grade.
Kainit and muriate should not be used, as both of
these gave detrimental results.
Phosphoric Acid.-Bone meal was one source of
phosphoric acid that gave uniformly good results.
Thomas slag gave results nearly as good. Dissolved
bone black when genuine can also be relied upon.
Acid phosphate used by itself gave uniformly bad
results, which were largely counteracted, however,
when air-slaked lime to the amount of 750 pounds
per acre was applied after the application of the fer-
Lime.-Various forms of lime, both in the carbon-
ate and air-slaked form, were used on a small num-
ber of plants. No strikingly good effect was seen
from its use.

The formula which seemed to give best results
under the experimental work for the growing pine-
apples, that is, before they came into fruiting, was:
ammonia 4 per cent, potash 6 per cent, phosphorus
total 6 per cent.
The formula that appeared to give best results for
the fruiting crop ran: ammonia 5 per cent, potash
10 per cent, and phosphorus total 5 per cent.
The experiments on fertilizers were completed at
the time when potash could be obtained at about $1
a unit. It is quite certain that with the present price
a lower per cent of potash would prove to be more
economical, but at the price of potash before the war
the larger per cent seemed most satisfactory.


The amount of fertilizer that can be profitably
used will vary with its price and the price at which
the crop can be sold. Taking the above formula as
a basis, the most profitable amounts to use per acre
range from 2,250 to 3,750 pounds annually. The
number of applications of fertilizer which may be


recommended is either three or four. The more fre-
quent the applications, the less the loss through
leaching; and if the intervals between fertilization
are long, the plants are likely to suffer from lack of
plant food at one time, and over-feeding at another.
Analyses of a large number of fruits (Red Span-
ish), covering a period of four years, showed that
the eating quality of the fruit is not affected by the
kind of fertilizer used. The sugar content of the
fruit is slightly increased by heavier fertilizer appli-
cations. The large fruits contain a greater per-
centage of sugar than the small ones, and a slightly
smaller percentage of acid.

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