ProductionTimes UF FLORIDA
MGreenhouse Edition IFAS Extension
Volume 17, Number 2
Production Times is brought to
Lelan Parker, M.S.
Office: (407) 254-9200
FAX: (407) 850-5125
This material is provided as one of the many
services relating to the educational programs
offered to you by this agency. Our statewide
network of specialists is prepared to provide
current information on agriculture, marketing,
family and consumer sciences, 4-H, marine
science, and related fields. We will be happy to
help you with additional information upon
Use of trade names in this newsletter does not
reflect endorsement of the product by the
University of Florida, Institute of Food and
Agricultural Sciences, or the Florida Coopera-
tive Extension Service.
See the newsletter online at:
Learn how to identify nutrient
deficiencies on page 2
PESTS TO WATCH!
By Lelan D. Parker
As the weather is warming up there are a few new and old pests to be on the
lookout for. For more information on pests you can go to: http://
www.doacs.state.fl.us/pi/enpp/pi-pest-alert.html and http://mrec.ifas.ufl.edu/
Mikania micrantha Kunth is a climbing hempvine that
was detected near Homestead, FL. It is also known as
the Chinese Creeper, Bittervine or Mile-A-Minute.
Mikania micrantha is native to Mexico, Central and
South America and the West indies. It is an aggres-
sive vine that can grow over and smother vegetation
and nursery crops. It is included on the Noxious
Weed List for Florida.
Nipaecoccus virdis (Newstead) is a new exotic mealybug that has been detected
in Palm Beach County. The host plant it was found upon was dodder (Cuscuta
exaltata Engelm). This is an agricultural pest
in Asia that attacks food, ornamental crops
and fiber crops and forage. The body color
is black, purple to blue green with a thick
white or pale yellow wax. In older infesta-
tions wax may turn yellow and mealybugs
turn black in 70% of alcohol. It has been in-
tercepted at US ports on Punica sp., Nephe-
lium sp., Eugenia sp., and Citrus sp.
Tetranychus urticae Koch, the twospotted spider mite, is a major -
pest of ornamental plants and vegetable crops grown in green- .
houses. Mites can be dispersed on greenhouse personnel
clothing, infested plant material and silken threads. Patchy
greenhouse infestations are characteristic of these mites. Phyto-
seiulus persimilis and Neoseiulus californicus are two natural ene-
mies used to control twospotted spider mites.
The Institute of Food and Agricultural Science (IFAS) is an Equal Employment Opportunity Institution authorized to provide research, educational information and other services only to individuals and
institutions that function without regard to race, color, sex, age, handicap or national origin U S DEPARTMENT OF AGRICULTURE, FLORIDA COOPERATIVE EXTENSION SERVICE, UNIVERSITY
OF FLORIDA IFAS FLORIDA A & M UNIVERSITY COOPERATIVE EXTENSION PROGRAM AND BOARDS OF COUNTY COMMISSIONERS COOPERATING
Identifying Nutrient Deficiencies
Summarized by Lelan D. Parker
There are 17 nutrients that are required for healthy plant reproduction and growth. The plant
will begin to exhibit deficiency symptoms when essential nutrients in plant tissue are at levels be-
low specific needs of the plant. Nutrient deficiencies may reduce plant growth, flowering or aes-
thetic appeal if left untreated. Fertilizers are often applied to provide essential nutrients and cor-
rect plant deficiency symptoms. Essential plant nutrients are divided into two main groups (1)
macronutrients and (2) micronutrients. Nitrogen (N), phosphorus (P), potassium (K), calcium
(Ca), magnesium (Mg), and sulfur (S) are plant macronutrients. Iron (Fe), zinc (Zn), manganese
(Mn), copper (Cu), molybdenum (Mo), boron (B), nickel (Ni) and chlorine (Cl) are plant micronu-
The first step to visual identification of a nutrient deficiency is to determine where on the plant
the symptoms are appearing. A nutrient is considered mobile if the plant is able to move it from
one part of the plant to another as it is needed. In contrast, immobile plant nutrients cannot move
to different plant parts. Therefore deficiency symptoms of mobile nutrients appear first in older
plant parts, whereas immobile nutrients will be seen first in new growth. Symptoms of N, P, K
and Mg deficiencies will manifest in the older growth because they are mobile, while symptoms
of Ca, Cu, B, Fe, Mn and Zn deficiencies will appear in the new growth because they are immo-
Next determine the characteristics of the symptoms. Leaves may appear chlorotic or yellow in
color or there may be dead tissue. Also, symptoms may be present on the leaf tip or be in-
terveinal. Once a nutrient deficiency has been identified actions can be taken such as fertilizer ap-
plications. However, before fertilizers are applied, a soil test should be completed to determine
the nutrient status and pH of the growing media. This is important because in a highly acidic K,
Ca and Mg may exist in a chemical form that plant roots cannot absorb even if these elements are
present in sufficient amounts.
Yellowing on old growth Deficiency on new growth
For more information go to: http://edis.ifas.ufl.edu/pdffiles/SS/SS53000.pdf
SBy Lelan D. Parker
In pesticide storage facilities fires pose a special hazard. Flammable pesticides typically include
the precaution statement: "Do not use or store near heat or open flame". Fire warnings will be
found in the Physical and Chemical Hazards Statements on the product's label. Potential problems
that are associated with pesticide fires include: (1) The pesticides may be highly flammable or
explosive, (2) The pesticides may give off highly toxic vapors or smoke that may harm firefight-
ers, nearby residents, animals or plants, (3) Pesticide residues may be present in the debris and
soil following a fire at a pesticide storage facility, and (4) Runoff from the fire site may contain
highly toxic chemicals.
Proactive Pesticide Fire Measures include:
* Locating the storage facility as far as possible from places where people and animals live
* Notify the local fire department of the location and the contents of the pesticide-storage facil-
* Carefully map a floor plan of the facility and the immediate surrounding area.
* Train local workers in execution of the emergency plan.
* Keep the storage facility locked at all times.
* Post signs that indicate pesticides are stored in the facility.
* Store combustible pesticides away from steam lines and other heating systems.
* Do not store glass or pressurized containers in sunlight, where they can concentrate heat and
possibly explode or ignite.
* Keep a written inventory of the pesticides held in storage and file the list away from the stor-
For more information go to: http://edis.ifas.ufl.edu/pdffiles/PI/PI22300.pdf
R Trouble Shooting for Unrooted Cuttings
1. Leaves yellow in propagation after first week.
A. Temperature too warm or too cold. ..
B. Misting too much.
C. Nutrients leached out of cuttings.
2. Cuttings stop developing but are not mushy or yellow.
A. Temperatures are too cold
B. Misting too much. ..
C. Woody cuttings are still dormant. Unrooted Cuttings
By Lelan D. Parker
Pest populations can be resistant or susceptible to a pesticide. When one pesticide is used repeatedly in
the same place against the same pest, the surviving pests may be more resistant to the pesticide than the
original population was. Resistance may develop rapidly with pests that have many generations per year
and when multiple generations are exposed to a pesticide. Ornamental production in greenhouse often
incorporates a combination of these factors that contribute to resistance. The main objectives of a resis-
tance management program in greenhouse production should be to minimize the number of exposures of
pests to pesticides with a similar mode of action and use non-chemical approaches such as biologicals, for
Crops should be scouted on a regular basis and pesticide applications should be made only when pest
densities reach economic injury levels. When a pesticide is needed, products should be rotated among the
different modes of action indicated on the pesticide label. Care can be taken to rotate crops, use pest resis-
tant species and varieties, set pest-free transplants, conserve and release natural enemies, etc. Pest-specific
tactics are available for particular situations such as elimination of excessive moisture in order to kill fun-
gus gnat larvae in greenhouses.
For more information go to: http://edis.ifas.ufl.edu/pdffiles/IN/IN71500.pdf
16- Nursery Crop Insurance Lunch n' Learn. Apopka, FL Mid-Florida Research & Education Center. To RSVP contact:
Jennifer Parrish firstname.lastname@example.org 407-880-7883
1- Aquatic Pesticide License Review and Exam. Orlando, FL at Orange County Extension. To register: Yamira Donato
18- Right of Way Review and Exam. Orlando, FL at Orange County Extension. To register: Yamira Donato 407-254-
20-21- Paint Your Own Financial Future. Orlando, FL at Rosen Plaza. For info: Linda Reindl 407-295-7994 or go to:
31- Small Farms Conference. Kissimmee, FL at Osceola Heritage Park. For info: http://smallfarms.ifas.ufl.edu