The eggplant (Solanum melongena) is a native of the subtropical areas of south-eastern
Asia and was introduced into Europe by early Arab traders. It is a member of the Solanaceae
family, which includes other vegetable crops such as tomatoes, potatoes and capsicums.
Eggplants have been widely grown in southern Europe, the Middle East and Asia for hundreds
The fruit, also known as aubergine (France), melanzana (Italy) or brinjal (India), is considered
something of a delicacy. It can be baked, grilled, fried or boiled, or used in stews or as a
Eggplant is a summer-growing vegetable that requires warm to hot conditions over a 5–6
month growing period to produce high yields and quality fruit. Periods of cool weather during
the growing period will retard plant growth and reduce yields. Affected plants seldom recover,
even if favourable growing conditions return. Young seedlings are sensitive to frost.
The optimum growing temperature range is 21°–30°C, with a maximum of 35°C and a
minimum of 18°C. The optimum soil temperature for seed germination is 24°–32°C.
Eggplants are moderately deep rooting and can be grown on a wide range of soils. They
do best on light-textured soils such as sandy loams or alluvial soils that are deep and free
draining. These soils warm up quickly in spring and are suitable for early plantings. Avoid soils
with high clay content. A soil pH in the range 6.0–7.0 is desirable.
The plant can be a perennial but in commercial production it is treated as an annual bush.
Fruit shapes vary from the more common teardrop shape to round to slim ‘sausage’ shape.
Fruit colour is predominantly glossy dark purple to black but fruit of newer varieties are
available in light purple, crimson and cream colours.
Eggplants are usually planted in the field as seedlings. Transplant seedlings need to have 6–7
leaves and be 10–12 cm high.
Bed preparation should start several months before transplanting. Eggplants are best transplanted
into raised beds for better drainage and only when soil temperature is above 20°C.
Plant spacing will depend on the vigour of the variety. For single or double row planting of
smaller growing varieties, plant spacing can be set at 50–60 cm apart within rows and 60–80
cm between rows. Larger growing varieties do best when planted 60–80 cm apart with 100–
120 cm between rows in an alternate planting pattern. A trellis support system is needed to
keep the fruit off the ground and to reduce wind damage. The most common system used in
two-row plantings is stakes (steel or wood) on the outside rows with one or two lines of wires
(2 mm) or heavy duty twine supported by ties. Stakes are placed 3–4 m apart with a strainer
post at each end of the row. Branches with fruit are trained up between the wires or twine.
DISEASES AND PESTS
The main pests that affect eggplants are:
- fruit and flowers – tomato caterpillars, eggplant caterpillars, fruit flies, aphids, looper caterpillars
- leaves – leaf-eating ladybirds, spider mites, tomato russet mites
- roots – cutworms, root knot nematodes.
Diseases cause fewer losses in eggplants than do insect pests. Verticillium wilt is the most
serious disease. Symptoms include discolouration of the conducting tissues in the lower stem
and roots of plants, wilting and eventual death of the plant. Avoid planting in areas known to
be affected or after tomatoes, potatoes or capsicums. Practise crop rotation with vegetables
such as peas and beans.
Anthracnose is the main fruit disease that attacks ripening fruit, causing circular sunken
spots. The main leaf diseases are target spot and leaf blight.
selected text from Agfact H8.1.29, third edition 2003