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and maintained
by Debbie Roos,
Ag Extension Agent.
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North Carolina
Cooperative Extension
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Sunny Slope Greenhouses
Photos and text by Debbie
Roos, Agricultural Extension Agent.

| This is a 2-3 week old transplant.
A good transplant shoot is as wide as it is tall. The trays that
the seedlings are produced in have a hole in the bottom that air
prunes the tap root which encourages feeder root development. |

Dave transplants seedlings into the larger cells.
Note how every other row is filled to give plants room to develop.
Dave selects and plants only the best 2,500 seedlings out of the
original 3,300 planted. As the transplants grow, light and temperature
regimes are adjusted to maximize plant growth and to compensate
for weather conditions.
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| These plants have been growing
in the larger cells for about 2-3 weeks and are filling in the extra
space. |

| These plants are ready for transplanting
into the ground. Dave and Jim will select and plant the best 2,200
plants out of these 2,500 transplants. |

Planting is done the week between Christmas and New Year's.
While the transplants have been growing, Jim and Dave have incorporated
the compost and lime (if indicated on soil test reports), tilled
the beds, laid out and tested drip irrigation lines, covered the
beds with white plastic, and cut holes for plants. Black plastic
would absorb heat and reduce fuel costs but white plastic reflects
light better and light is the biggest factor that they can't control.
Remember that they are growing tomatoes at the time of year when
days are the shortest and light level is the lowest.
Before the crop is planted they run the heaters
for 24 hours and submit air samples to NCSU to make sure that
no harmful gases are emitted. They use five 220,000 BTU furnaces,
one for each bay. Fuel is the major expense. On a night when it
gets down to 32° F, they burn 100 gallons of propane.
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It takes about a day per bay to transplant and
apply a starter fertilizer solution to each plant to help establish
roots. During the growing season, fertilizer needs are determined
based on plant tissue analysis. Every 7-10 days, they send a sampling
of tomato leaves off for analysis and then apply fertilizer based
on the resulting report. Water-soluble fertilizer is injected
into the drip irrigation system.
You can see part of the trellis system in this
photo: notice the bobbins hanging in the top left of the photo
- the bobbins are placed on overhead wires, one above each plant,
and each contains 25 feet of twine that is lowered down to touch
the plant.
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Plant spacing varies throughout the greenhouses
but each plant has approximately 4 square feet. Plants in interior
bays get about 20% more space because they don't get as much light.
Note that the plants still are just about as wide as they are
tall.
Around January 1, right after transplanting,
Jim and Dave inject millions of beneficial nematodes through the
irrigation system to control soil-borne pests such as thrips and
fungus gnats. Nematodes are tiny roundworms that live in the soil.
Many species feed on plant roots and are considered pests but
other species are entomopathogenic, or parasites of insects. These
beneficial nematodes, purchased from suppliers that specialize
in biological control agents, parasitize insects that spend all
or part of their life cycle in the soil.
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| Speaking of biological control
agents...another natural enemy that Jim and Dave purchase and release
is the Trichogramma wasp, an egg parasitoid that seeks
out eggs of the tomato fruitworm, which damages fruit. These micro-wasps,
measuring only about 1/10" in size, are too fragile to be shipped
as adults and so they are shipped ready to hatch inside parasitized
eggs glued to a card. Each card contains approximately 120,000 eggs.
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| Jim cuts the cards into individual
strips to disperse around the greenhouse. |

Close-up of parasitized eggs, which are dark
with developing wasps inside. Normal eggs are white. |

| Jim attaches the cards to the
plants in the areas that he knows are most susceptible to fruitworms
- usually near vents and doors and openings. |

The adults emerge from the eggs and search for fruitworm eggs
to parasitize in the greenhouse. The wasps are ordered and released
monthly in the spring as the temperatures warm up and the fruitworm
moths become active and start laying eggs.
Sunny Slope employs other biological control agents on an as-needed
basis, including predatory lady beetles and lacewing larvae, parasitic
Aphidius wasps and predatory Aphidoletes midge
larvae for aphid control, parasitic Encarsia wasps for
whitefly control, and parasitic nematodes.
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This page last updated January
16, 2006.
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URL:
http://chatham.ces.ncsu.edu/growingsmallfarms
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Carolina Cooperative Extension is an educational partnership helping people
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