Eggplant (Solanum melongena) is a warm-season vegetable in the nightshade family, native to South Asia and now cultivated on every inhabited continent. Fruit shape, size, and color vary widely — deep purple globes, long slender Japanese types, small Thai varieties, and white or striped forms are all the same species. It is among the most heat-dependent of common vegetables, requiring a long frost-free season and consistently warm soil to produce well.
Start seed indoors 8–10 weeks before the last frost date, maintaining soil temperature at 80–90°F for reliable germination. Transplant only after soil temperature reaches 60°F and nights are reliably above 55°F. Black plastic mulch accelerates soil warming and suppresses weeds. Eggplant shares pests and soilborne pathogens with tomato, pepper, and potato; rotating out of the Solanaceae family every 3–4 years reduces verticillium and fusarium pressure. Fruit is ready when the skin is glossy; dull skin signals overripeness and seed development.
Purple-skinned fruit contains nasunin, an anthocyanin with documented free-radical scavenging activity in laboratory studies. The flesh is rich in chlorogenic acid, one of the higher-concentration plant phenolics found in vegetables. Eggplant is a culinary staple across the Mediterranean, Middle East, South Asia, and East Asia, central to dishes such as baba ganoush, baingan bharta, moussaka, and ratatouille.
Verticillium Wilt
Lower leaves yellow and wilt, often on one side of the plant, with brown streaking in the stem and crown tissue when cut open. Plants are stunted and decline over the season.
Remove and destroy affected plants. Avoid planting in soil that has grown infected tomatoes, peppers, or other susceptible crops. Rotate beds and improve drainage; there is no cure once a plant is infected.
Fusarium wilt
Sudden wilting, brown streaks in stems, yellowing leaves. Affects sweet basil varieties most.
No cure. Remove and destroy plants. Do not replant in the same spot for 3+ years. Choose resistant varieties.
Phytophthora Root Rot
Wilting despite moist soil, yellowing leaves, stunted growth, and dark, decayed roots and crown tissue. Vines may collapse during hot weather.
Plant in well-draining soil and avoid waterlogging. Remove and destroy affected vines. Improve drainage with raised beds or amended soil and avoid overwatering.
Early Blight
Dark brown spots with concentric rings on older lower leaves, surrounded by yellowing. Leaves drop, exposing fruit to sunscald.
Remove affected leaves, mulch to block soil splash, water at the base, and rotate crops. Apply copper or chlorothalonil fungicide if it spreads.
Damping Off
Seedlings collapse at the soil line with thin, water-soaked stems; seeds may fail to emerge or rot before sprouting.
Sow in well-draining mix, avoid overwatering, and ensure good airflow. Remove affected seedlings and let the surface dry between waterings.
Root-Knot Nematode
Swollen galls on roots, poor vigor, wilting in heat, and reduced fruiting. Containers and sandy soils are more prone.
Use clean potting mix in containers. Avoid replanting in infested soil. Maintain plant vigor with mulch and steady watering. Solarize affected garden soil.
Botrytis (grey mould)
Grey fuzzy mould on petals and stems, worst in cool wet conditions.
Remove affected parts immediately. Improve air circulation. Avoid overhead watering. Apply copper fungicide if severe.
Mosaic virus
Yellowing, mottled, or distorted leaves. No cure — spread by aphids.
Remove and destroy infected plants. Control aphid populations to prevent spread. Do not propagate from infected tubers.
Cercospora Leaf Spot
Small round spots with tan or gray centers and reddish-purple borders on leaves. Spots merge in severe cases, causing leaves to brown and die back.
Remove infected leaves and avoid overhead watering. Space plants for airflow and rotate crops. Apply a copper-based fungicide if the infection spreads.
Phomopsis Blight
Irregular brown lesions on leaves, stems, and fruit. Stem lesions can girdle the plant, causing wilting above the infection point. Fruit develops sunken, dark, water-soaked spots that expand and rot rapidly in warm, wet conditions. Small black fruiting bodies may be visible inside older lesions.
Remove and destroy all infected tissue. Avoid overhead irrigation and improve air circulation through adequate spacing. Apply copper-based fungicide at first symptoms and repeat every 7–10 days during wet weather. Rotate out of the nightshade family for at least 3 years and start with certified disease-free transplants.
Flea Beetle
Alticini →Small round shot-holes scattered across leaves; tiny dark beetles that jump when disturbed. Heavy feeding stunts young plants.
Use floating row covers on seedlings. Remove crop debris and weeds that harbor beetles. Apply kaolin clay or spinosad if damage is severe.
Spider Mites
Tetranychus urticae →Fine stippling or bronzing on leaves, faint webbing on undersides, foliage drying out during hot, dry weather.
Spray foliage with a strong jet of water to dislodge mites. Apply insecticidal soap or horticultural oil to leaf undersides; repeat every 5–7 days as needed.
Aphids
Aphididae →Clusters of small soft insects on new growth and flower buds.
Knock off with a strong jet of water. Ladybirds and lacewings are natural predators. Insecticidal soap as last resort.
Colorado Potato Beetle
Leptinotarsa decemlineata →Yellow-orange eggs in clusters on leaf undersides. Orange larvae with black spots and adult yellow-and-black-striped beetles feed heavily on foliage, rapidly skeletonizing leaves and stunting young plants. Defoliation can be severe enough to eliminate fruit production.
Hand-pick egg masses, larvae, and adults into soapy water daily during peak emergence. Apply spinosad or Bacillus thuringiensis var. tenebrionis (Bt-t) targeting early larval instars. Use row cover over transplants until flowering. Rotate nightshade crops to new locations each year to disrupt overwintering beetle populations.