Title: Production times
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00090492/00008
 Material Information
Title: Production times
Series Title: Production times
Physical Description: Serial
Language: English
Creator: Institute of Food and Agricultural Sciences, University of Florida
Publisher: Institute of Food and Agricultural Sciences, University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: Winter 2008
 Record Information
Bibliographic ID: UF00090492
Volume ID: VID00008
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.


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Production UF FLORIDA

STimes IFAS Extension

Winter 2008
Volume 15, Number 4

Cowpeat for Potting Media
Adapted from Qiansheng Li "For Peat's Sake "

Production Times is brought to
you by:

Juanita Popenoe, Ph.D.
Lake County
Woody Omamentals/Multi-County
(352) 343-4101

Lelan Parker, M.S.
Orange County
Greenhouse/Foliage Multi-County
(407) 254-9220

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 in color at:

Researchers at the University of
Florida supported in part by the
Florida Department of Agriculture
and Consumer Services are cur-
rently testing cowpeat for it's use as
a major potting media component
for foliage plant production and
propagation. Peat is a major com-
ponent of soilless media used for
containerized ornamental plant pro-
duction. However, peat is apart of
the wetland ecosystem. Peat har-
vesting releases carbon dioxide into
the atmosphere. Thus, peat harvest-
ing is being regulated and peat
prices are continuing to rise as the
supply decreases. With the rapid
expansion of ornamental plant pro-
duction, there is an increased need
for alternative organic materials that
can be partially or completely sub-
stituted for peat. Cowpeat may be
an alternative for peat. Cowpeat is a
composted material derived from
dairy manure.

For the experiments, researchers
used a commercial media formula-
tion, 20% perlite and 20% vermicu-
lite with 60% Canadian or Florida

peat based on volume as controls.
Next, the peats were replaced with
cowpeat at 10% increments up to
60% which resulted in 14 potting
media tested. Physical and chemi-
cal characteristics such as micro and
macro nutrients, porosity, water
holding capacity, EC, pH, bulk den-
sity, etc. were tested and results in-
dicated that the media formulated
with cowpeat were similar to those
formulated with either Canadian or
Florida peat.

Formulated media were used for
germinating seeds of Asparagus
densiflorus 'Sprengeri', Chlorophy-
tum amaniense 'Fire Flash', and
Schefflrea actinophylla 'Umbrella
Tree', and rooting cuttings of
Epipremnum aureum 'Golden Pot-
hos', Philodendron scandens oxy-
cardium 'Heartleaf Philodendron',
and Ficus benjamin 'Weeping
Fig'. The media formulated with
cowpeat showed little difference in
the percentage of seed germination
and rooting compared to those for-
(Continued on Page 4)

Pest Alert-Maranta Mite! The Maranta mite, Steneotarsonemusfurcatus, is a serious problem on
Maranta, Calathea, as well as Stromanthe cultivars. Early signs may appear as necrotic lines that
parallel the margin of the leaves. Chemicals and biological control have shown to have little to no
affect on this mite. Many operations have chosen to discontinue growing susceptible varieties. For
more info go to: http://mrec.ifas.ufl.edu/foliage/folnotes/maranta.htm

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

Plant Clinic Problem of the Quarter -
Cylindrocladium is a fungus that attacks in the warm summer months and can cause severe damage
to Spathiphyllum and other foliage plants. The first symptoms noticed are yellowing lower leaves
and wilting. This is caused by the extensive root damage this pathogen causes. Reddish brown le-
sions on the roots rapidly expand, causing total root collapse and rot. Thousands of spores are pro-
duced in these infected root masses and move from plant to plant via water. When splashed on the
leaves, the spores cause dime sized circular brown spots surrounded by yellow halos. When infec-
tions are detected, plants showing severe symptoms should be removed and the remaining plants
drenched with the appropriate fungicide. Dr. Norman at MREC has published research on the web
at http://mrec.ifas about fungicide trials. He found that no chemicals provided complete protection
from infection under the high disease pressure of his experiment, but Cleary's 3336, fluazinam and
Terraguard reduced disease severity ratings.

SNA 2008 Research Roundup
By Juanita Popenoe

Watch out for Roundup
Do you use glyphosate around the trunks of your
trees? If you do, you need to know the latest re-
sults from a study in Ohio. The new formula-
tions of glyphosate have more surfactants to help
them work faster. These surfactants also help the
chemical get through bark and into the trees you
are trying to protect if you are not extremely
careful when applying. Their research indicates
that glyphosate is taken up through thin or col-
ored barked trees, and once in the phloem of the
plant can take years to break down. It is stored

in the roots with sugars, and can be translocated
back to new growing tips in the spring, causing
carryover injury. A sub-lethal dose may take a
few years to show symptoms as the chemical ac-
cumulates. The symptoms include witches
broom, stunting, bark cracking or splitting, loss
of apical dominance, individual dead limbs, yel-
lowing leaves, reduced cold hardiness and death.

Soil Moisture-how to tell when to irrigate
The root ball is the most important area to meas-
ure moisture for scheduling irrigation, not the


(Continuedfrompage 2)
surrounding soil. Irrigation when the root ball
was at 10% soil moisture reduced water use
without significantly affecting plant growth. Re-
searchers measured a 53% reduction in nitrogen
runoff going from overhead irrigation on a time
clock to overhead irrigation based on a soil
moisture sensor. Another researcher looked at
different ways to determine when to irrigate.
They found that guessing when to irrigate
wasted 50-150% excess water. Using the leach-
ing fraction method took too much time, but
gravimetric scheduling (based on the weight of
the container) used the least water, caused the
least leaching and was easy to use. The idea is
that weight loss=water loss. They used a load
cell and weighed a plant/pot at a container ca-
pacity and scheduled the irrigation to come on
when the weight loss was 94-98% of container
capacity initially, then reduced that to 92-96% of
container capacity later in the season, and even
less in the fall.

Root Splitting
Splitting the root ball 2/3 up, quartering the root
ball or leaving the root ball undisturbed at trans-
planting caused no difference in shrub growth.

Pine Tree Substrate
Pine tree substrate (PTS, made from whole pine
trees rather than just the bark) required addi-
tional nitrogen fertilizer-about 100 ppm more for
herbaceous plants and about 4 lbs more con-
trolled release for woody plants. This was de-
pendent on particle size and PTS storage time.
The larger the particle size, the less surface area,
the lower the water holding capacity, the higher
the air space, the fewer microbes breaking it
down, and the less nitrogen is immobilized by
the microbes. By controlling particle size with

grinding and amendments, you can create the
media with the characteristics you want.

Fertilizer rates and Philodendron acclimation
Nitrogen needed for chlorophyll and plants in
low light will need more chlorophyll to capture
all the light energy the plant needs. But plants
put into lower light levels to acclimate do not
need more fertilizer. There was an increase in
chlorophyll within three days of plants being
put in low light levels but this was not affected
by fertilizer level. Acclimation took about one
week regardless of fertilizer. The plants in low
light and low fertilizer mobilized other sources
of nitrogen within the plant to make the needed

Persistent fertilizer pollution
EDTA, used in micronutrient fertilizers, medi-
cine, toothpaste and industry is not biodegrad-
able and has become a very common persistent
pollutant that the European Union is very con-
cerned about. EDTA is used to make micronu-
trients more accessible to plants, but wild in the
environment, it can extract metals from the soil
and make them more able to leach. EDDS is bio-
degradable and so far has shown to be a suitable
replacement. Joe Albano from the USDA in Ft.
Pierce is doing further work to make EDDS ac-

Read about these research results and more and

(Continued from Page 1)
ed with Canadian or Florida peat. Then the media was used for production ofDieffenbachia x 'Star Bright' in
6 inch pots Nephrolepis exaltata 'Boston Fern' as hanging baskets in 8-inch pots, and Epipremnum aureum
'Golden Pothos' on poles as climbers in 8-inch pots either from tissue culture liners or cuttings. Plants were
kept in greenhouses and data showed that cowpeat could completely replace peat up to 60% without damag-
ing effects on plant growth. The replacement of cowpeat may possibly allow reduced fertilizer application
because of nutrients supplied in the cowpeat. Further studies are being performed to evaluate nitrate nitrogen
and phosphorus leaching from potting media. The composting of dairy manures minimizes the environmental
problems associated with peat mining as well as converting manures into organic materials for potential in-
come for dairy producers in Florida. Cowpeat can provide the ornamental industry with an alternative to peat
which in turn will contribute to the well being of Florida's natural environment.

For more information about this study refer to Li, Qiansheng, Chen, J., Popenoe, J., and L. Parker 2008: For
Peat's Sake, Ornamental Outlook. August 2008: 24-25.

Power Units for Greenhouse Operations
By Lelan D. Parker

Your valuable plants in the greenhouse may be lost or damaged due to a power outage. It is not al-
ways necessary to provide standby power for all greenhouse electrical equipment, however the suc-
cessful operation of some greenhouse equipment requires the availability of electricity at all times.
An auxiliary power unit may give you that extra insurance against losses or brown outs. A standby
power system consists of a generator, an engine or tractor to power the generator as well a transfer
switch. For more information go to: http://edis.ifas.ufl.edu/pdffiles/ae/ae03300.pdf

2008 Planning Calendar
Links to most programs and agendas may be found at: http//cfextension.ifas.ufl.edu or the UF Extension Calendar at http]/

18-Limited Commercial Landscape Maintenance License Review and Exam. Seminole County Exten-
sion Office. (407) 665-5551.


6- CEU Day and Workers Protection Standards Train the Trainer. Orange County Extension Office.

(407) 254-9200

19-Expanding Your Plant Palette. Harry P. Leu Gardens. (352) 343-4101.


3,10, 17-Nursery and Greenhouse Integrated Pest Management Scouting Training. Apopka, FL.

Mid-Florida Research and Education Center. (407) 254-9200

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