Cole Crops in Mississippi
The cole crops are cool season vegetables derived from the Brassica oleraceae L. plant. They include kale, collards, cabbage, broccoli, cauliflower, kohlrabi, Brussels sprouts, and Chinese kale. Kale and collards are discussed under the greens heading. The other plants were developed for different parts to be eaten. Mississippi produces approximately 400 acres of cabbage and less than 50 acres each of the rest of the cole crops. At one time, Mississippi was a major player in the spring cabbage market.
Frequently Asked Questions
How much boron fertilizer do cole crops require?
The cole
crops have a high requirement for boron. Boron is added at two pounds
per acre on sandy soils and soils with a history of boron deficiency.
Boron deficiency symptoms are expressed as brown streaks through the
stem of the crop.
What causes one leaf in a cabbage head to turn brown?
The
browning of one leaf in cabbage is called internal tipburn. It is technically
a calcium deficiency, but is most often caused by uneven water availability
during the growing season. Never allow cabbage to wilt before applying
irrigation.
Why are cauliflower leaves tied over the head?
Only
pure white cauliflower attracts good prices. The curd of cauliflower
will develop a cream color, or even a green color, if it is exposed to
long periods of sunlight. Leaves are tied over the head to provide protection
from the sun. This is called blanching. Self blanching types have been
developed that have upright leaves which protect the head without tying.
Why are high domed broccoli varieties recommended?
Mississippi
normally has a high relative humidity and dew every morning. The high
dome of the broccoli head helps to shed water and allow the beads to
dry out more quickly. Water on the head for several hours can lead to
bacterial growth and soft rot.
Which insects cause the holes in cole leaves?
Most
of the visible damage caused by insects is due to two larvae. The imported
cabbage worm and the diamond backed moth lay eggs on the leaves of cole
crops. The larvae which hatch are voracious eaters and cause the holes
in the leaves. The larvae prefer young leaves. Be sure to spray the underside
of young leaves with an approved insecticide to control them.
Why aren't other cole crops grown in Mississippi?
Cauliflower
is the most difficult of the cole crops to grow successfully. It is damaged
at 26 degrees and is very intolerant of high temperatures. Mississippi's
climate will not allow consistent success with cauliflower. Brussels
sprouts require longer periods of cool weather than Mississippi normally
experiences. Kohlrabi grows well, especially in the fall, but there is
a very small market.
How often can I plant in the same field?
Cole crops
should not be planted in the same field for three consecutive years.
Rotating to crops will help prevent the build up of disease organisms
in the soil. Crops to include in the three year ban are greens, turnips,
radishes, rutabaga and rape. All of the Brassica's share the same diseases.
What type of soil do cole crops need?
Cole crops
can be grown on any type of soil as long as water does not stand on it.
Soils with poor internal drainage need to be leveled and sloped so water
will runoff quickly.
What should plant spacing be for cole crops?
Cabbage
and broccoli are often grown with two rows about one foot apart on beds
40 to 42 inches apart. Plants within the row are spaced 18 inches apart.
This creates a plant population of approximately 18,000 plants per acre.
The rest of the cole crops are grown at about 9,000 to 12,000 plants
per acre. There must be air movement in a cole crop field to allow drying
of leaves. Always arrange rows parallel to prevailing winds if possible.
Higher plant populations often lead to increased disease pressure.
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