Cultivating

cabbage

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 Production guidelines

I
WHAT TO TAKE INTO ACCOUNT
t’s easy to grow cabbage, but pests Crop Rotation
and diseases need to be controlled Rotate cabbages with nonrelated crops
throughout the growing cycle. Cabbage such as tomatoes, pumpkin, sweet
(Brassica oleracea) is a cole crop and potatoes, beans, peas, potatoes or maize.
belongs to the Cruciferae family, which Cabbage is a heavy nitrogen feeder and
includes broccoli, mustard, cauliflower, should be rotated with leguminous crops
Brussels sprouts and kale. such as beans, which fix nitrogen, as well
as with grain crops such as maize for their
It is a cool season crop, but new varieties production of organic matter.
are extending the seasonal range. Avoid cruciferous crops such as broccoli,
Inexperienced farmers, however, find Chinese cabbage and cauliflower, as they
it difficult to grow cabbage during hot can act as hosts for pests and diseases.
months, when more insects attack the
crop. Cabbage is a very popular vegetable Cultivar list
in South Africa and people use it in various Choose the cultivar that suits the climate
ways. It can be eaten with pap, mixed in your area. Such cultivars should also be
with meat and added to stews or salads. in demand locally. For more information
Cabbage has a high fibre content, and also contact the seed companies or the
contains vitamin C, calcium and folic acid. Agricultural Research Council’s Vegetable
and Ornamental Plant Institute (ARC VOPI).
Soil • Autumn and spring:
Cabbage can be grown in virtually all types Conquestador,Gladiator.
of soil. The crop can be grown successfully • Spring and late summer:
in well-drained fertile soil containing lots Tenacity,Conquestador.
of organic matter. A soil pH of 6,5 to 7 is • Late summer (Jan. – Feb.):
recommended. Hercules,Drumhead, Grand Slam.
• Late summer to autumn: Megaton
Climate (good cold tolerance; harvest in spring).
Although cabbage is a cool weather crop, it • All year in mild areas: African Sun.
can be grown throughout the year in most
areas, especially when suitable cultivars are Sowing
used. It is fairly resistant to frost and can Sow seed in a nursery and transplant about
survive temperatures as low as -3°C without three to four weeks later. Prepare a fine
harm, but thrives in an optimal temperature seedbed. Make shallow drills (furrows) 15cm
range of 15 — 20°C. Poor environmental apart and a finger nail deep and sow seeds
conditions during the growing period can 5cm apart in the row. Cover the seeds with
lead to quality problems when the cabbages light soil and gently compress the soil with
are harvested. your hand. Put dry grass on top of the bed
to stop the soil drying out. Irrigate seeds
High temperatures and low moisture levels every day during cooler weather and twice
may result in small plants and a low yield. a day during hot, dry seasons. Remove the
Too-low temperatures during the growing grass four to five days after the seedlings
period can also lead to long stems and emerge. If the grass is left on for too long,
bolting (flower stalk formation and seeding). plants become leggy and get sunburn. The
seedlings should be ready for transplanting
four to six weeks later.

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A research trial at ARC-VOPI where the impact of various fertiliser combinations (organic or inorganic) in
cabbage yield was determined.

Spacing Transplanting
The planting distance depends on the Soil should be irrigated before
cabbage variety and the target market. transplanting. At this stage plants should
Varieties that have big heads need more be about 10cm high. Transplant during
space than cultivars having small heads. the morning or late in the afternoon when
it is cooler. Remove the seedlings from
Small-head varieties:
the seedbeds or trays with soil or growth
plant 30cm apart in the row and 50cm
between rows. These varieties are ideal medium adhering to the roots. Make holes
for fresh produce market purposes. in the soil and transplant the seedlings in
the holes. Plant them a little deeper than
Big-head varieties: they stood in the nursery. Press the soil
50cm apart in the row and 70cm between down around each plant, but not too
the rows. These varieties are ideal for close to the stem. Water immediately.
hawkers’ markets.
The transplants can be hardened off
Planting times before planting, thus gradually exposing
In South Africa, cabbage can be
them to field conditions in order to
grown throughout the year, except on
reduce incidences of transplanting
the Highveld where the crop should
preferably not be sown from May to July shock. Transplant only healthy, good-
because of the cold, and also not in the quality seedlings that have growth points.
summer months in the Lowveld, or any Discard long-legged, weak seedlings and
other region which experiences very hot those that look unhealthy.
and humid conditions.

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 Production guidelines

These Grand Slam cabbage plants are ready for harvesting.

Fertilising Too much water, once the heads have

Cabbage is regarded as a heavy feeder formed, can cause them to crack, which
and does very well if fed with manure and is unwanted. Cracking can also result from
compost, as well as with organic fertilisers. watering inconsistently, e.g. first giving the
A correct fertiliser recommendation can plants a lot of water, then giving them a little.
only be made after soil analysis. Use drip irrigation to conserve water.
The following is a general recommendation:
before planting, dig in 2:3:4 (27) at 600 — Harvesting
900kg/ha or 60 — 90g per m2. Consider Harvesting comes 90 — 110 days after
this as the minimum needed to ensure that transplanting. Cut with a sharp knife when
the plants get a good start. About 1 200kg the heads are firm and hard.
of 2:3:4 (27) per ha (120g/m2) is, however, Harvesting may continue selectively over
optimal. The plants respond well to an several weeks and should always be done
additional top dressing of nitrogen LAN at early in the morning. Harvested cabbage
two, four and six weeks after transplanting. heads should not be left in the sun to wilt.
Start with 4g per plant and increase later to Cut heads with two to three layers of outer
10g per plant. Spread 20cm around plants. leaves for protection during transportation.
Applying the top dressing late, when the Store heads in a cool, shaded place. With
cabbages are already forming heads, can efficient management practices, good
cause splitting or the development of more yields of 60 — 80t/ha can be obtained.
leaves, resulting in poor or loose head
formation. Crop management
Start weeding when the plants are
Irrigation established and continue at least until the
It is crucial to supply sufficient water at leaves cover the ground. Take care not to
critical times, such as immediately after damage the roots when weeding is done
sowing or transplanting. Young plants mechanically. Irrigate as required throughout
should get enough water for vegetative the growing period. Mulches can also help
growth before forming heads; the bigger the conserve moisture.
plant is at this stage, the larger the eventual Crop residues should be destroyed
head will be. About 35mm per week is immediately after harvesting by
optimal. incorporating them into the soil.

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 Pests, diseases
Various pests and diseases attack cabbage, and
this can lead to serious economic loss. Generally
speaking, integrated pest management strategies,
including scouting, crop rotation, good crop
management, chemical and mechanical control of
pests and diseases can be used. If you use chemicals,
make sure they are registered.
An updated list of chemicals can be obtained from the
Department of Agriculture.

PESTS
Aphids
Aphids suck the leaves of the plants and cause
serious damage to the plants.
Cabbage bagrada bug.
Bagrada bugs suck sap from the leaves of the
plants, and can damage the growing points of the
seedlings, causing the cabbage to make several small
unmarketable heads.

Diamond back moth

The small greenish larvae eat window-like holes in
cabbage leaves, damage the growing points and may
cause serious damage to the crop.
Control: Growers must check their seedlings, young
plants and growing plants regularly (scouting).
Window-like patches in the leaves are sure signs of
the presence of diamond back moth larvae. Consult
an agricultural supply store about chemical control.

DISEASES
Black rot Cabbage diamond black moth.
Caused by Xanthomonas campestris pv. campestris.
The leaf edges turn yellow-brown and dry out, and the
veins turn black. When cut open, the xylem (woody
area of stem) shows blackening. No treatment is
effective if the plants are already infected. Remove
infected plants immediately and destroy them.
Control: Plant disease-free seed
Crop rotation. Apply field sanitation
Plant resistant cultivars

Downy mildew
Caused by Peronospora parasitica, the downy mildew
fungus can live in the soil until the next crop. Pepper-
spot lesions are present on the upper leaf surface,
with white growth present on the lower leaf surface.
Control: Chemical control, Plant disease-free
Windowlike damage caused by larvae of t
seedlings, Don’t over-irrigate

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 Production guidelines

Club root
Caused by Plasmodiophora
brassicae. Plants are stunted and
yellow, with large swellings on the
roots.
Control: Chemical control. Plant
disease-free seedlings. Long crop
rotation (7 years) Add lime if soil is
acidic. Control weeds around planting

White rot
White fluffy growth is present on
leaves and stems causing rot and
wilting of plants, and is caused by
Sclerotinia sclerotiorum.
Control: Plant disease-free healthy
seed
Chemical control works but nothing
registered in S. Africa. Control weeds
around field. Crop rotation. Don’t
over-irrigate

Black leg
Caused by Phoma lingam. Large
brown lesions develop on the stem
and leaves, with small black spots
visible inside the lesions.
Control: Only plant seed treated
against black leg, or buy seedlings
from a good nursery. Crop rotation.
Plant in well-drained soils

General control measures against

cabbage diseases:
Practice a 3- 4 year crop rotation.
Do not water in the evening. Water
early in the day so that leaves can dry
before night fall.
Try not to work in plantings when they
are wet.

Use only disease-free transplants.

Remove and destroy infected plants.
Spray with registered chemicals.

by larvae of the diamond black moth.

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 Introduction

RSA sowing and planting chart for the most popular vegetable crops*
Crop Sowing time Transplanting time Harvesting time
Potatoes Aug. Nov.
Sept. Dec.
Feb./Mar. Jun./Jul.
Beetroot Jan./Feb. Thin out at a later stage May/Jun.
Mar./Apr. Jul./Aug./Sept.
Jul./Aug. Nov./Dec.
Green beans Aug./Sept. Nov./Dec.
Oct. Jan./Feb.
Jan. Apr.
Feb./Mar. May/Jun.

Carrots Feb. Thin out 5 — 7 days after germination May/Jun.

Mar./Apr. Jul./Aug.
Jul./Aug. Oct./Nov.
Sept. Dec./Jan.
Cabbage Beginning of Feb. Mar. Jun./Jul.
End of Mar. May Aug./Sept.
Jun./Jul. Aug./Sept. Nov./Dec.
Aug./Sept. Oct./Nov. Dec./Jan.
Sweet Oct. Feb./Mar.
potatoes Nov. Mar. — May
Dec. May — Aug.
Pumpkin Aug./Sep. Dec. — Feb.
Jan. Mar./Apr.
Squash Aug./Sept. Nov./Dec.
Oct. Jan./Feb.
Jan. Apr./May
Lettuce Feb. Thin out 5 — 7 days after germination May/Jun.
Apr. Jul./Aug.
Jun. Sept./Oct.
Aug. Nov./Dec.
Tomatoes Aug./Sept. Oct. Jan. — Mar.
Nov. Dec. Mar./Apr.
Dec. Jan. Apr./May
*Please consult the seed company in your region regarding cultivars, which vary from area to area.

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