GREEN

BEANS
G
reen beans (Phaseolus vulgaris) are a legume Local names: Green beans
that has been used as food for centuries, and is Sesotho: Dinawa
Swati: eenabhontjisi
today still one of the most important foodstuffs
Xitsonga: Tinyawa
utilized by mankind. The pods contribute vitamins such Thsivenda: Nawa
as vitamin C, and minerals such as calcium, iron, folic Sepedi: Dinawa
acid and riboflavin (vitamin B2) to the human diet. Setswana:
Green beans are a popular vegetable and are grown isiXhosa” Iimbotyi
isiZulu
in home gardens. Green beans are a tropical crop and
IsiNdebele
consequently sensitive to low temperatures. In general
farmers plant both bush as well as runner varieties.

Soil
Green beans can be successfully Cultivars
cultivated in soils which range from sandy Bush beans: Wintergreen, Contender, Class
to reasonably heavy clay soils. They Act, World Cup, Imali, Malelaan, Star 2000,
prefer deep, well-drained soils, with good Star 2052
water retention ability. The best yields are Runner beans: Witsa, Lazy Housewife
achieved in medium loam soils. Avoid soils
making a crust, as this will have a negative Crop rotation
effect on emergence of seedlings. Green beans should be rotated with other
A soil pH of 6.0 to 6.5 is recommended. non-leguminous crops to avoid possible
transmission of diseases such as bacterial
Climate blight, anthracnose and fusarium-wilt. As a
Because of its tropical origin, green beans result of their nitrogen-fixing ability, green
cannot be successfully cultivated in areas beans help to build up the soil nutrient
with temperatures below 10°C and they status.
are very sensitive to frost. The optimum
temperature is between 16°C and 24°C. Propagation
Temperatures above 35 ºC, if accompanied Green beans establish well by direct sowing.
by dry winds, may cause the flowers and
tender pods to abort resulting in poor yields.

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 Production guidelines

Spacing Soil Preparation

Plants are established from seeds. The Loosen the soil thoroughly by either
optimum spacing for bush beans is 60cm ploughing or using a hand hoe, fork or a
between rows and 5cm between plants in spade. All clods should be smashed by
a row (32 plants/m2). For runner beans a using a rake until you obtain a deep fine
wider spacing is used: rows 1m apart and bed. Old manure, compost or fertilizer
plants spaced 10cm apart in the row. To should be incorporated thoroughly into the
reduce costs of trellising, 3 plants can be soil during soil preparation. Cover crops
trellised to one support. (green manure) can be planted and worked
into the soil 4-6 weeks before establishing
the crop.

PLANTING TIME
PLANTING TIME
PRODUCTION AREA
BUSH BEANS RUNNER BEANS

Highveld (heavy frost in winter) Middle September to Middle September to

of Gauteng, North-West & Mpu- January December
malanga.

Middleveld (light frost in winter) September to February September to February

of Gauteng, Northern Province,
Mpumalanga & KwaZulu-Natal.

Lowveld (cooler areas of Mpu- August to September & August to September

malanga, Northern Province & February to March & February to March
KwaZulu-Natal).

Lowveld (with very hot sum- March to August March to August

mers & frost-free winters) of
Mpumalanga, Northern Prov-
ince & KwaZulu-Natal.

KwaZulu-Natal Midlands September to January September to Decem-

ber

Free State & Northern Cape October to January October to December

Eastern Cape October to February October to December

Western Cape September to February. September to January.

Summer Vegetables 035 035 Summer Vegetables

 Fertilization To ensure good keeping quality for the
General fertilizer recommendation: fresh produce market, green beans must be
Before planting, approximately 1000 kg/ha cooled and stored at 4 to 7 ºC.
or 100 gram/ m2 2:3:4(27) must be applied Estimated yield: 100 kg/100m2.
and worked into the top 10 cm of the soil.
After planting, apply a top dressing of 10 Pests
gram LAN/ m2 at 2 and again at 4 weeks Bean seed beetle
after planting. Be careful not to apply LAN Damage the seed during storage.
or any other nitrogen fertilizer directly onto Seed bean maggot
the plants, because this will burn the leaves. This pest causes poor seedling emergence.
Apply 5-10 cm away from the plants at both The maggots feed on the young seedlings.
sides. Water the plants immediately after A sporadic pest.
the fertilizer has been worked into the soil. CMR-beetle
Or use organic fertilizers before planting e.g. Feeds on all above-ground parts of the
compost or manure (4 handfulls of manure/ plant especially the flowers.
m2). Cover crops (green manure) can be Brown beetle
planted and worked into the soil 4-6 weeks Active at night and cause damage to the
before establishing the crop. leaves.
Thrips
Irrigation Damage young developing pods.
Roots will develop and utilize water and African bollworm
nutrients up to 400 mm down into the soil. The caterpillar penetrates the pods and
Approximately 450 mm of water is required continues feeding inside.
during the growing season including rainfall. Plusia looper
A general guideline is 35 mm per week. Damage pods in the field.
Green beans dislike water on the seed Tip wilter
while germinating (5-7 days after sowing). Flat-backed, blackish, insects. They attack
After sowing water properly and wait for soft growth points by sucking out plant sap
emergence. From the flowering stage, green and injecting toxins that causes the plant to
beans are very sensitive to lack of moisture, wilt. Damage is similar to that of the green
so it will be necessary to apply 35 mm per vegetable bug.
week until the pods have been harvested. General control measures for the above
insects:
Harvesting Scout regularly
Green beans generally take 60 – 90 days to Apply pesticides. Consult your agricultural
mature. supply outlet for recommendations.
Repeated harvests when the pods are still Apply insect repellent sprays e.g. onion and
young, will induce the formation of new garlic mixtures.
flower buds which will result in a higher yield
of young pods. Aphids
It is important to harvest at the right stage Suck sap from plants, and transmit virus
and the following method can be applied: diseases.
When the pod is cut open lengthwise, the Control: Spray with soapy water. Spray
seed must be well developed, but be careful repellent mixes e.g. onion and garlic mix.
because the seed can harden very quickly. Red spider mite
Beans ripen very quickly in warm weather Present on the underside of leaves where
and therefore it is necessary to harvest they feed on plant sap and spin silk threats
every day to get good quality pods. It is and webs. Small light yellow specks appear
important to harvest early in the morning, on the upper leaf surface.
and pods must not be left in the sun as they Control: Regular scouting is very important.
wilt quickly (within 2 to 4 hours). Spray with registered miticides.

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 Production guidelines

Root knot nematode Stems show a dark brown, lower stem rot
Infested plants show signs of retarded and root rot.
growth. The roots are malformed with small Control:
growths on the roots. Infested plants can Chemical seed treatment
die before they start to produce fruit. Pre-plant chemical drench
Control: Fallowing. Practice crop rotation. Shallow planting
Cropping with marigolds, castor beans, Crop rotation with non-host crops
chrysanthemums. Soil solarisation – cover
tilled, slightly moist soil with clear plastic Rust
sheeting for 6-8 weeks in sunny areas. Caused by Uromyces appendiculatus.
Leaves are covered with round, reddish-
Diseases brown powdery spots.
BACTERIAL DISEASES Control:
Bacterial blight Chemical control
Caused by Xanthomonas phaseoli. Small Resistant cultivars
to large brown spots with yellow margins Crop rotation with non-host crops
occur on leaves. Water-soaked spots occur Scab
on the pods. Caused by Elsinoë phaseoli which attack
Control: leaves, stems and pods showing raised red/
Use disease-free seed brown necrotic areas.
Chemical control Control:
Crop rotation Use disease-free seed
Sanitation practices Crop rotation with non-host crops
Chemical seed treatment
FUNGAL DISEASES Sclerotinia stem rot
Anthracnose Caused by Sclerotinia sclerotiorum. Infected
Caused by Colletotrichum lindemuthianum. plants become covered with a white fungus
Reddish-brown leaf spots and sunken growth containing irregularly shaped black
lesions on the fruits. bodies called sclerotia.
Control: Control:
Use disease-free seed Use disease-free seed
Chemical control Chemical control
Crop rotation Plant in well drained soils
Ashy stem blight Don’t over-irrigate.
This is caused by Macrophomina
phaseolina. Stems and pods are grey / VIRAL DISEASES
white and contain small black bodies called Bean mosaic virus
sclerotia.. The margins and tips of the leaves curl
Control: down. The leaves show a typical yellowish-
Use disease-free seed green mosaic; dark-green bands along the
Optimal fertilization and irrigation veins show up against the lighter green of
Crop rotation the leaf. This is a seed-borne virus.
Plant in well drained soil Yellow mosaic viruses
Fusarium root rot This group of viruses causes bright yellow
Caused by Fusarium spp. Stems show a spots on the leaves. Infected leaves are
brown rot at soil level, and roots are brown. often misshapen. The disease can cause
Control: considerable crop losses.
Chemical seed treatment Necrosis viruses
Optimal fertilization This group of viruses causes dwarfing of
Good drainage infected plants. Leaves, stems and other
Crop rotation. organs become completely or partly brown
Rhizoctonia root rot and die. This disease can cause severe
Rhizoctonia solani causes this disease. damage.

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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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