The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source
site maintained by the Florida
Cooperative Extension Service.
Copyright 2005, Board of Trustees, University
R. T. Poole L.S. Osborne a -A -R-Cha
University of Florid iH I EJB RAR
Agricultural Research Center ApopkIBRARY
ARC-A Foliage Plant Research Note R1984-.Ej
h 40' ij1,503
There is much confusion about the no .fr.aeuf\H dav.ati, a
popular seasonal plant native to Brazil. a r rWF now call
the Thanksgiving, Christmas and Easter cacti, Holiday cacti. The scientific
as well as common names have also changed throughout the years. Currently
the Christmas cactus is identified as Schlumbergera bridgesii (Lem.) Lofgr.,
the Thanksgiving cactus, Schlumbergera truncata (Haw.) Moran, and the Easter
cactus, Rhipsalidopsis gaertneri (Regel) Moran.
Christmas cacti have cladophylls, or joints, with 2 to 3 rounded teeth
on margins, an ovary that is 4 to 5 angled, and purple anthers. Margins of
the cladophylls of Thanksgiving cacti are 2 to 4 serrated, the ovary is
cylindrical and anthers yellow. Grown under normal daylength, Thanksgiving
cacti normally bloom near Thanksgiving, approximately a month before Christ-
mas cacti. However, by manipulating daylength, growers can bring both species
into bloom for the Christmas season. Easter cacti have cladophylls with cre-
nate margins and bristles at the apex. Flowers have angled ovaries and spread-
ing stigma lobes. They bloom primarily in the spring and sporadically through-
out the year.
Holiday cacti are available in a range of flower colors including white,
yellow, orange, pink, red, lavender and a few bicolors. Other characteristics
which differ among cultivars are density of branching, stem texture, shape of
cladophylls, shape of flowers and time of bloom. Although flower color is
the primary criterion which consumers evaluate when purchasing Holiday cacti,
producers must evaluate performance, particularly the ability of specific
cultivars to bloom in time for holiday sales. Holiday cacti grow best in
light shade of 65 to 80% (approximately 1500 to 3000 foot-candles) with the
higher shade level preferred. Excellent growth can be obtained with 3-1-2
ratio liquid or slow release fertilizer when applied at a rate of 1200 to
1400 Ibs N/A/year (equivalent to 28 to 33 Ibs N/1000 ft2/year). Micronutrients
should be added. Potting media utilized must have excellent aeration as
Holiday cacti do not grow well in heavy, wet mixes. Good growth occurs when
soil temperatures are 700 to 800F, with similar air temperatures. Limited
growth will occur at 600F soil temperature, but lower temperatures result in
poor or no growth.
1Professor Plant Physiology; Assistant Professor Entomology; and Associate
Professor Plant Pathology, respectively, Agricultural Research Center,
2807 Binion Road, Apopka, FL 32703
Symptoms Upper cladophylls (leaves) are chlorotic, roughly in the
center of the plant.
Control Although micronutrient deficiency has been suggested as the
cause, treatment with various micronutrients has not been beneficial.
Suspected causes are low soil temperatures encountered in the late
fall and early winter.
Symptoms Portions of cladophylls are blue to gray green, and sometimes
Control Symptoms are sometimes induced by root rot pathogens, but
frequently result from soil with poor aeration or overwatering.
Reduce the frequency of irrigation and improve soil aeration.
3) Flower-bud drop
Symptoms Newly formed flower buds abscise.
Control Continued warm temperature above 90F will cause some abscission
of flower buds. Maintain temperature below 90F.
4) Non-flowering plants
Symptoms Flower buds are not produced in the fall-winter seasons.
Control Maintain complete darkness during the night. Night lights
or car lights can interrupt the dark period required to set flower
buds. A second cause of non-flowering plants could be low light
during the day. Maintain 1500 ft-candles, or more during the day for
maximum flower production.
DISEASES OF HOLIDAY CACTUS
Holiday cacti are subject to numerous diseases caused by fungi, bacteria
and nematodes. These problems are encountered frequently during production by
many growers. Root problems and leaf spots can be avoided if pathogen-free
materials are employed and good sanitation and cultural controls are practiced.
1) Soft rot (Erwinia spp.)
Symptoms A blackened, wet,slimy lesion generally starts at the soil
line at the base of the plant and progresses into the top of the clado-
phyll and into other segments of the plant. Plants wilt, collapse
and often die. Schlumbergera spp. are known hosts of these
Control Remove and destroy infected plants as soon as they are
found. Keep watering to a minimum and avoid splashing since
this can spread the bacterium to other plants. Irrigate early
in the day to allow rapid drying of the foliage which reduces
the ability of the bacterium to infect. Be sure to obtain an
accurate diagnosis of the problem since several of the diseases
caused by fungi appear similar.
1) Drechslera leaf spot (also called Helminthosporium leaf spot)
Symptoms Blackened, sunken lesions from 1 mm to 1 cm wide form on
the cladophylls of infected plants. The lesions are generally circ-
ular and can occur above or below ground. Cladophyll abscission is
common on plants even when infection appears light. The black spores
of the fungus form in the lesions, giving them a fuzzy appearance.
Rhipsalidopsis sp. is very susceptible to Drechslera leaf spot and
Schlumbergera sp. is moderately susceptible.
Control Use the same cultural controls as listed for soft rot. In
addition, sprays and drenches of Daconil are very effective in con-
trolling the disease. Benlate is not effective against this pathogen.
2) Fusarium leaf spot and stem rot (Fusarium oxysporum)
Symptoms Dieback, root and stem rot and leaf spots may occur as a
result of a Fusarium infection. Both Schlumbergera and Rhipsalidopsis
spp. are susceptible to F. oxysporum. An infection appears as a
water-soaked area near the soil line and often the lesion has a red
border. Lesions are generally tan and may be dry at times and appear
sunken. The orange-colored spores of the pathogen form in the lesions,
and they spread easily by water or air since the spores are light. One
of the easiest ways to distinguish between Fusarium and Drechslera
leaf spots is to observe the color of the spores since they are radi-
cally different (Fusarium-tan, Drechslera-black). The possibility of
both diseases occurring concurrently should be kept in mind when
choosing control procedures.
Control Use the same cultural controls as listed for soft rot. Benlate
is labeled for use on this plant and is effective in controlling
3) Pythium and Phytophthora root and stem rot (Pythium and Phytophthora
Symptoms -Foliage of plants infected with Pythium or Phytophthora spp.
turns gray-green and may wilt. Stems become rotted at the soil line
and upper portions of the plant collapse. Cladophyll abscission may
occur. Roots are darkened and mushy and generally sparse.
Control Use pathogen-free pots and potting media and grow plants
on raised benches. Overwatering plants may predispose them to attack
by root-rotting fungi. Soil drenches with Banrot, Truban or Subdue
each aid in control of stem and root rots caused by these two orga -
1) Cactus cyst (Cactodera cacti)
Symptoms Heavily infected plants become stunted, foliage turns red
brown and wilting is common. Examination of the roots reveals the
tiny round cysts which may be white when immature and turn golden to
medium brown when mature. The cyst is the female nematode and is
usually attached to the roots.
Control Many nematicides are effective in controlling this nematode
problem. Mocap provides excellent control but causes severe phytotox-
icity. Furadan and Vydate provide good nematode control and allow
normal foliage growth. Always raise plants above the ground and use
nematdde-free potting medium, pots and plant materials.
PHYTOTOXICITY OF FUNGICIDES AND NEMATICIDES FOR HOLIDAY CACTI
Banrot 40 WP
Benlate 50 WP
Chipco 26019 50 WP
Fungo 50 WP
Ornalin 50 WP
Temik 10 G
Truban 5 G
Truban 30 WP
Truban 25 EC
Vydate 2 L
Daconil 4.17 F
one of two
Pesticides were tested at recommended rates and intervals.
Both caused poor foliage growth.
The major insect pests of Holiday Cactus are due to soil inhabiting
insects such as fungus gnats and root mealybugs. However, foliar mealybugs
and scales sometimes attack this plant. In the control section for each
pest a few of the many registered and effective pesticides will be listed.
For a complete listing, please consult the references at the end of this
1) Fungus Gnats
Symptoms Small black flies are observed running around the soil
surface or on leaves. The larvae are small legless "worms" that
inhabit the soil. The larvae spin webs on the soil surface which
resemble spider webs. 'Damage is caused by larvae feeding on roots,
root hairs, and lower stem tissues. Feeding damage may predispose
plants to disease.
Control Reduce the amount of water applied to each pot where possi-
ble. Avoid algae growth on walkways, benches, and cooling pads. Soil
drenches and soil-surface sprays of Diazinon AG-500 and Vydate L or
application of granules (Temik O1G or Oxamyl 10G) are effective at
controlling the larvae.
Symptoms Mealybugs appear as white, cottony masses in leaf axils, on
the lower surfaces of leaves and on the roots. Honeydew and sooty
mold are often present and infested plants become stunted, and with
severe infestations, plant parts die.
Control Systemic materials are preferred. Examples of chemicals which
have systemic activity are Metasystox-R and Orthene. Dycarb, Dursban
and Enstar 5E appear to be as effective as some of the systemic
materials. Root mealybugs can be controlled with applications of Temik
1OG, Diazinon AG-500, Oxamyl 10G, or Vydate L to the soil.
Symptoms Infested plants become weakened or stunted and, in severe
cases, die. Scales can be found feeding on the cladophylls. Their
shape, size, and color are variable and many are hard to distinguish
from the plant material on which they are feeding.
Control See Mealybugs
PHYTOTOXICITY OF INSECTICIDES TO HOLIDAY CACTUS
Diazinon AG-500 Orthene 75 SP
Pesticides were tested at recommended rates and intervals.
1. Chase, A. R, 1983. Phytotoxicity of some fungicides used on trop-
ical foliage plants. ARC-Apopka Research Report, RH-83-2.
2. Short, D. E. 1978. Phytotoxicity of insecticides and miticides to
foliage and woody ornamental plants. Extension Entomology Report
3. Short, D. E. L. S. Osborne, and R. W. Henley. 1982. 1982-83
Insect and related arthropod management guide for commercial foliage
and woody plants in Florida. Extension Entomology Report #52.
4. Simone, G. W. and A. R.
for foliage production.
Chase. 1984. Disease control pesticides
Plant Protection pointer No. 30 (revision 2),
Mention of a commercial or proprietary product or of a pesticide in this
paper does not constitute a recommendation by the authors, nor does it imply
registration under FIFRA as amended. Pesticides should be applied accord-
ing to label directions. Those pesticides listed in the control sections
for each disorder but not listed in the phytotoxicity charts HAVE NOT been
tested for plant safety at the University of Florida.