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PINEAPPLES IN FLORIDA
By WILLIAM H. MATHEWS
The pineapple, Ananas comosus (Linn.) Merr., has long been
considered by many as the finest of all fruits grown. In reality,
it is not a single fruit but a number of fruitlets grown together
on a common stem. The fruit sits on top of the fruit stalk or
peduncle, which rises some 18 inches above the leaves. Botan-
ically, the pineapple belongs to the family Bromeliaceae, which
includes such other familiar Florida plants as Spanish moss and
the common air plants.
During the late 1890's and early 1900's, Florida had a flour-
ishing pineapple industry, primarily along the Indian River.
In 1908-09, well over a million crates of pineapple were har-
Fig. 1.-Fine pineapples such as this formerly were grown extensively
in Florida. With effective insect control methods, a number of growers
are again producing pineapples successfully.
vested from approximately 5,000 acres. Shortly after this, low
prices, a new malady called "red wilt", and the freezes of 1917
and 1918 virtually ended this Florida industry.
Today, a number of commercial plantings are located in south
central Florida and along the East Coast. During the 1955-56
season, some 9,000 boxes of pineapples were marketed from
these plantings. In addition, many residents raise pineapples
in their yards, both for the fruit they produce and for their
tropical appearance and unusual habit of fruiting.
Pineapple plants will stand temperatures as low as 280 F.,
but growth ceases between 55 and 600 F. Fruit subjected for
any length of time to temperatures even in the 40's are affected
by a condition called heart rot. The other extreme is also un-
desirable-950 F. is considered as a maximum temperature for
successful production of pineapples. The best possible range of
temperatures for the pineapple is from 70 to 90 F.
Variation in amount of rainfall suitable for pineapple pro-
duction is very wide. Anything from 20 to 80 inches of rainfall
per year is considered satisfactory. Florida, with an average
of about 50 inches per year, is right in the middle of this range.
Unfortunately, this rainfall is not always distributed properly
for best fruit production.
Most soils in central and southern Florida can be used for
growing pineapples if they are well drained. Drainage can be
either natural or the result of a system of ditches and beds.
For best results, the soil should be well drained, porous, slightly
acid (pH 5.5 to 6.0), and sandy, with a minimum of 12 to 18
inches of rooting depth.
Most Florida soils available for pineapple production are low
in natural fertility. Any practice which tends to maintain or
increase the organic matter content of these soils, such as grow-
ing cover crops or additions of organic matter, is considered to
be a great help. The cost of purchasing and applying most or-
ganic materials to large areas is prohibitive. Thus the most
practical approach to this problem is the use of a cover crop.
Such leguminous cover crops as hairy indigo and crotalaria are
excellent, but even a heavy growth of native grasses turned under
Soils underlain with marl or limestone are sometimes used
for the production of pineapples with relatively good success.
These soils, while generally thought of as alkaline, are probably
acid in that portion near the surface in which the pineapple
roots are actually growing.
A number of varieties of pineapple can be grown with suc-
cess in Florida. The one grown in largest quantity in the past
was Red Spanish. Although generally considered a poor quality
fruit, when "gassed" for winter sale it is superior to Smooth
Cayenne and Abakka. The plant is a hardy, vigorous grower,
somewhat disease resistant.
First in world importance is Smooth Cayenne, due largely
to the fact that it has enough fiber to can well. This variety is
being raised in Florida and is favored by some because of its
nearly spineless leaves.
Variety Normal Weight Flesh Color
Red Spanish May-June 3-5 lbs. White
Natal Queen June-July 1-2% lbs. Yellow
Pernambuco June-Aug. 2-4% lbs. White
Smooth Cayenne July-Sept. 5-8 lbs. Slightly yellow
Abakka July-Sept. 4-6 lbs. Yellow
Variety Flavor Texture Shipping
Red Spanish Sweet & spicy Coarse & juicy Excellent
Natal Queen Very sweet & rich Crisp & tender Excellent
Pernambuco Very sweet Very tender & juicy Good
Smooth Cayenne Sweet but tart Tender & juicy Good
Abakka Sweet Tender & juicy Poor
All varieties will produce some fruit out of their normal season and all can be forced
to fruit at other seasons.
Some commercial growers feel that Natal Queen is the best
all-around variety for this state. This variety produces an
abundance of suckers which can be used in propagating new
Pernambuco (Abacaxi, Eleuthera) is perhaps best for pro-
duction of sweet fruit when "gassed" for winter sale. This fruit
has a rich fragrance and is extremely juicy. It is considered by
some as the very finest quality pineapple which can be grown
for table use.
The variety most commonly grown in Florida today is Abak-
ka. It is a fruit of good quality for table use but is very subject
to black heart.
LAND PREPARATION AND PLANTING
Much time and money can be saved on weeding if all perennial
grasses such as Bermuda, maiden cane and others are eradicated
before the beds are planted. This can be accomplished by the
use of intensive tillage or chemical weed killers. The latter
method gives surest results. To do this, apply dalapon as a
foliage spray at the rate of 5 to 10 pounds of commercial material
in at least 50 gallons of water per acre.
Fig. 2.-Planting systems used in Florida. The 2-row system (left)
is used more in Hawaii than here. Florida growers use mostly the 4-row
(cover picture) or the 5-row (right) system.
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Young grass seedlings usually can be controlled with one
application, but when the grasses have become firmly established
a second and sometimes even a third application may be neces-
sary. Make the second application 7 to 14 days after the first.
For maximum effect, disk or otherwise cultivate the land about
7 to 14 days after the second application. Wait one month after
the last application before planting the pineapples.
For best results grow a cover crop (see under Soils) one
season prior to planting. Work this cover crop into the soil well
and have the beds as level as possible at time of planting.
Pineapples are planted either 2, 4 or 5 rows per bed. Florida
growers use mostly 4- and 5-row beds.
On flatwoods soils, where water drainage is a problem, it
is customary to plant on raised beds with a water furrow at least
18 inches deep between each two beds. Well-drained soils do
not need this precaution.
Pineapple plants are usually set close together. Distances
range from 12 to 18 inches between plants in the row, 18 to 21
inches between rows. In areas where drainage is not a prob-
lem and the plantings are level, the beds are 3 to 4 feet wide,
depending on number of rows per bed and distance between rows.
It is customary to leave a work aisle of 3 or 4 feet between the
beds. When the plantings are to be made on soils requiring
drainage ditches, it is customary to set up the system with 15
feet from center to center of the beds. This gives a flat-topped
bed 8 feet wide with a 7-foot water furrow between.
Do not place the planting piece too deeply into the ground
because of danger of sand sifting into the bud, which may injure
or kill the plant. To help prevent this, it is wise to place a small
quantity of some bulky organic material, such as ground tobacco
stems, castor pomace or cottonseed meal, in the bud of each plant
shortly after it is set. If the bud should become filled with sand,
wash it out with a gentle stream of water.
The number of plants required to plant an acre will vary,
depending on the particular system of beds and planting dis-
tances used. Keep in mind that the more plants there are on
an acre the larger yield in tons per acre. This is true even
though there may be a slight reduction in individual fruit size
with the thicker settings. For maximum production use 13,000
to 16,000 or more plants per acre.
Early spring-as soon as danger of frost is over-is the best
time to set new plants, especially if a winter crop is desired.
Planting can be done at any time during spring or summer, but
certainly should be completed by September.
The pineapple is propagated by planting pieces taken from a
mother plant. These planting pieces are usually one of the fol-
lowing: crown, slip, or sucker.
Those planting pieces which arise from the top of the fruit
itself are referred to as crowns.
Slip is the name given to planting pieces arising from the in-
florescence. These are of two general types, those which arise
from the fruit and those which arise from the fruit stalk or
Suckers originate from buds in the leaf axils along the stem,
both above and below the ground. It is customary to refer to
those suckers which originate on the aboveground portion of
the stem simply as "suckers," while the ones coming from the
Fig. 3.-Either the crown (A), a slip (B), or a sucker (C)
can be used to start a pineapple plant.
belowground portion of the stem are called "ratoons" or "ground
Any of these planting pieces will serve to produce new pine-
apple plants, but slips and suckers are most often used. It is
wise to do some selecting of planting material when gathering
slips. It is better to use slips which originate on the fruit stalk
rather than the ones that arise from the fruit itself. These latter
tend to pass along the characteristic of slip production on the
fruit. This results in a reduction of fruit size and the forma-
tion of fruits less desirable for the market.
These planting pieces are cut from the mother plant, dipped
in a solution of Systox (see Insects) and planted. In Hawaii,
these planting pieces are dried one week to three months in the
sun. However, in Florida, the planting material is apt to decay
if not planted within a few days after removal from the mother
plant. Planting material of any size may be used, but the larger
the planting piece, the sooner it will produce fruit.
TIME NEEDED TO PRODUCE NORMAL FRUITING IN HAWAII
Planting Date Months from Planting to Normal Fruiting
Sucker I Slip Crown
March .................................. 17 26 29
September ........................... 26 29 31
At least 2 crops of fruit should be obtained from a field
before replanting is necessary. Only 1 fruit is produced on
each stem. Subsequent crops are produced on suckers which
develop from the original plant. These are commonly referred
to as "ratoon crops". Natal Queen should be replaced every
3 years; and the others as the need is indicated by poor crop
When replanting an old field, remove or plow in all the old
plant material to help keep the mealybug population to a min-
imum. Also, the use of a soil fumigant such as DD at the rate
of 25 to 30 gallons per acre to control nematodes in an old field
There are no hard and fast rules about the fertilization of
pineapples in Florida based on research. Many growers are
using a 100% organic program and others a nearly 100% in-
organic program. In either case, certain fundamentals should
The pineapple has a very limited root system, both in depth
and in width. This is especially true for several months after
the plants are set. During this period it is essential that the
fertilizer be placed either in the lower leaf axils of the plant or
very near its base.
Once the plants become established and their roots fill the
area between plants, it is possible to spread the fertilizer evenly
over the entire surface of the bed. It is essential that the ferti-
lizer be kept out of the bud of the plant. One way to do this is
to fill the bud, prior to fertilizing, with some bulky organic ma-
terial. It is also best to omit all fertilizers for a month before
harvest begins and until harvest is complete.
The high cost of organic fertilizers makes a fertilizer pro-
gram using a combination of organic and inorganics highly
desirable. The following program-using a mixture of 6% ni-
trogen, 2% phosphoric acid, 8% potash and 4%o magnesium ox-
ide, alternately with sulphate of ammonia-is suggested. About
40% of the nitrogen in the 6-2-8-4 mixture should be derived
from organic sources. At time of planting, place a small amount
of cottonseed meal in the bud of each plant. Follow this in 4 to 6
weeks with 11/ ounces (3 tablespoons) of 6-2-8-4 mixture per
plant and repeat every fourth month. Between applications of
mixed fertilizer apply 1/4 ounce (1/ tablespoon) of sulphate of
ammonia to each plant. Repeat this rotation until one month
prior to fruit harvest and resume it following picking of the
It is impossible to suggest in what quantities the micro-
nutrient elements (copper, zinc, manganese, iron and boron)
might be needed, because of the lack of scientific data on pine-
apple nutrition under Florida conditions. Since most Florida
soils are naturally very low in these elements, it seems reasonable
to assume that some addition of them would be beneficial.
The organic material recommended in the fertilizer program
should take care of the plant's need for micronutrients. If diffi-
ciencies do occur they might be corrected by the use of water
solutions of the elements needed.
The addition of supplemental water is not generally practiced
in Florida. Irrigation probably could be used to advantage under
certain conditions. In Hawaii, where irrigation is becoming in-
creasingly important in some sections, it is felt that enough
water should be applied to maintain turgidity in the leaf. This
is commonly determined by cutting a leaf from the fourth whorl
back from the center of the plant in cross section. In examining
its makeup, if the layer of palisade or storage cells (the vertical
elongated cells lying just below the upper surface of the leaf)
is not about half the thickness of the tissue below it, the plants
are in need of water.
CULTIVATION AND WEED CONTROL
In pineapple production, cultivation is done solely to keep
weeds from growing in the beds. Any method which accom-
plishes this inexpensively without damage to the pineapple plant
The most common method of weed control in Florida pine-
apple fields is the use of a scuffle hoe or similar implement. This
method has the disadvantage of requiring much hand labor.
In Hawaii, asphalt-impregnated mulch paper is generally
used to prevent growth of weeds in the beds. This paper also
helps to conserve soil moisture. Thus far, this method of weed
control has not been used extensively in Florida, but possibly
it could be used to advantage.
In addition, many Hawaiian growers are using chemical weed
killers as a satisfactory method of weed control. Some Florida
growers also have tried weed killers and found them very effec-
tive. One of the most common used here has been monuron,
sold under the trade name of Karmex W.
Most of the varieties grown in Florida, if allowed to bloom
and mature their fruit normally, will produce a crop between
May and September. It is often very desirable to have pine-
apples fruiting at other times during the year. To do this, a
process for inducing bloom out of season can be used. This
forcing process is commonly called "gassing" in Florida.
The easiest and perhaps most common method of inducing
bloom out of season is to drop a few (10 to 12) grains of calcium
carbide into the bud of 18- to 20-month-old pineapple plants
(to obtain maximum fruit size and quality the plants should
weigh from 6 to 8 pounds) early in the morning when there is
a heavy dew. It is possible also to apply a small amount of
water with the calcium carbide and accomplish the desired re-
sult. The acetylene gas formed by the mixture of calcium car-
bide and water causes the early flowering.
Any of the unsaturated hydrocarbons, such as ethylene or
propylene, will do this. In some areas, the calcium carbide is
first mixed with water and the solution is applied. This method
has one major drawback: the acetylene gas is quite explosive
when under pressure or heat and must be handled with extreme
In Hawaii and Australia a growth regulator, the sodium salt
of naphthaleneacetic acid, is applied at the rate of 20 grams per
acre in 200 to 300 gallons of water, to promote early flowering.
When calcium carbide is applied fruit is ready for harvest
about 5 to 7 months later. This will depend upon time of year
applied and variety on which it is used. To put this practice into
its simplest terms, fruit ready for harvest in January must re-
ceive the calcium carbide treatment near the end of the preced-
ing July. Make the application to plants set out during March
one year prior to "gassing".
INSECTS AND DISEASES
Fortunately, the pineapple is not subject to great devastation
from insects and diseases.
Its primary insect pest is the pineapple mealybug, Pseudo-
coccus brevipes (Ckll.). This is a sucking insect about 1/6 inch
long. It is a fleshy, wingless, white or grey insect covered with
a mealy white waxy excretion. It is commonly found on the base
of the plant at or just below the surface of the soil and on the
tender portion of the leaves where they are pressed together.
As the mealybug sucks the plant juices, a type of wilt is
produced. This wilt causes the plant to be stunted and imparts
a red or reddish-yellow color to the leaves. Other characteristics
are light green spots on the leaves and withered, dead and dying
The insect is best controlled before the planting material is
set in the field. The easiest method is to dip the planting stock
in a malathion-water solution made by using 3 to 4 pounds of
25% wettable malathion or its equivalent in 100 gallons (3 to
4 tablespoons per gallon) of water or in a solution containing 1
quart per 100 gallons (2 teaspoons per gallon) of Systox (21.2%
liquid concentrate). This usually gives good commercial control.
To control this pest in pineapple beds, spray with malathion.
For best results, use a spray made of 3 pounds of 25% wettable
malathion, or its equivalent, per 100 gallons of water (3 table-
spoons per gallon). Apply 300 to 400 gallons per acre.
Ants will spread mealybugs from one part of the pineapple
field to another. If ants are present in or around the field, meas-
ures which control the ants, such as the use of chlordane or
other chemicals, will help to control mealybugs.
The pineapple mite, Dolichotetranychus floridanus (Banks),
sometimes called "red spider," can cause severe injury to young
plants. The most practical method of control is a preplanting
dip using 1 quart per 100 gallons (2 teaspoons per gallon) of
Systox (21.2% liquid concentrate). This has given control for
up to 5 months and also controls the pineapple mealybug. Sys-
tox is extremely toxic to man. Take precautions not to get the
dip on the operator. It does not have label clearance on pine-
apples for use at any time other than on planting stock before it
is put into the ground.
The pineapple fruit is often attacked at its base by a black
rot fungus when picked early and shipped long distances with-
out refrigeration. To prevent this, paint the cut surface within
two hours after harvest with a solution of salicylic or benzoic
acid, alcohol and water. The following formula is suggested:
Alcohol (95%) Water Benzoic or Salicylic Acid
32 cc 68 cc 2.5 grams
REMEMBER: When using malathion or Systox take pre-
cautions listed by the manufacturer on the label to prevent
PRODUCTION SCHEDULE FOR MID-WINTER FRUIT
This schedule will have to be varied somewhat, depending on
the fruit variety and variation in weather from year to year,
but it will serve as a general guide.
March: plant and apply cottonseed meal in bud.
April: apply 11/2 oz. 6-2-8-4 fertilizer mixture.
June: apply 1/4 oz. sulphate of ammonia.
August: apply 11/2 oz. 6-2-8-4 fertilizer mixture.
October: apply 1/ oz. sulphate of ammonia.
December: apply 11/2 oz. 6-2-8-4 fertilizer mixture.
February: apply 1/4 oz. sulphate of ammonia.
April: apply 11 oz. 6-2-8-4 fertilizer mixture.
June: apply 1/4 oz. sulphate of ammonia.
July: "gas" 10 to 12 grams calcium carbide in bud of plant.
August: apply 11/2 oz. 6-2-8-4 fertilizer mixture.
October: apply 1/4 oz. sulphate of ammonia.
January: first harvest of fruit.
February: apply 11/ oz. 6-2-8-4 fertilizer mixture.
The author expresses his sincere thanks to Dr. Oscar Zoebisch, man-
ager of Agricultural Research, Eastern Division, Libby, McNeil and Libby,
(formerly Assistant Manager of Research and Quality Control and As-
sistant Plantation Manager, Hawaiian Pineapple Division, Libby, McNeil
and Libby) for much of the material presented in this circular; to Dr.
H. S. Wolfe, professor of Fruit Crops, University of Florida, for many
valuable suggestions and for reading the manuscript; and to Mr. and Mrs.
H. J. Emminger, Lake Placid, Florida, for information and the use of
their plantings for pictures.
AGRICULTURAL EXTENSION SERVICE
COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS
(Acts of May 8 and June 30, 1914)
Agricultural Extension Service, University of Florida,
Florida State University and United States Department of Agriculture, Cooperating
M. O. Watkins, Director