Eggplant (Solanum melongena) is a plant species related to nightshade and native to India. Eggplant is grown worldwide for its edible purple fruit. The spongy and absorbent fruit is a staple in Eastern cuisines. This plant is known as “brinjal” in South Africa and Asia, while the British call it ‘aubergine’.
I. Appearance and Characteristics
Eggplant (US, CA, AU, NZ, PH), aubergine (UK, IE), brinjal (IN, SG, MY, ZA), or baigan (IN, GY) is a plant species in the nightshade family Solanaceae. Solanum melongena is grown worldwide for its edible fruit.
It was originally domesticated from the wild nightshade species thorn or bitter apple, S. incanum, probably with two independent domestications: one in South Asia, and one in East Asia. In 2021, world production of eggplants was 59 million tonnes, with China and India combined accounting for 86% of the total.
The eggplant is a delicate, tropical perennial plant often cultivated as a tender or half-hardy annual in temperate climates. The stem is often spiny. The flowers are white to purple in color, with a five-lobed corolla and yellow stamens. Some common cultivars have fruit that is egg-shaped, glossy, and purple with white flesh and a spongy, “meaty” texture. Some other cultivars are white and longer in shape. The cut surface of the flesh rapidly turns brown when the fruit is cut open (oxidation).
Eggplant grows 40 to 150 cm (1 ft 4 in to 4 ft 11 in) tall, with large, coarsely lobed leaves that are 10 to 20 cm (4 to 8 in) long and 5 to 10 cm (2 to 4 in) broad. Semiwild types can grow much larger, to 225 cm (7 ft 5 in), with large leaves over 30 cm (12 in) long and 15 cm (6 in) broad. On wild plants, the fruit is less than 3 cm (1+1⁄4 in) in diameter; in cultivated forms: 30 cm (12 in) or more in length are possible for long, narrow types or the large fat purple ones common to the West.
Botanically classified as a berry, the fruit contains numerous small, soft, edible seeds that taste bitter because they contain or are covered in nicotinoid alkaloids, like the related tobacco.
The eggplant genome has 12 chromosomes.
II. How to Grow and Care
Sunlight
Plant your eggplant in full sun where it will receive at least six hours of direct sunlight a day. Shade or partial shade will result in stunted plants with no or few fruits.
Temperature And Humidity
Eggplants are very sensitive to cold temperatures. Plant them in the garden in spring after your soil temperature has reached 70ºF. They are happiest while air temperatures are 70º to 85ºF, so wait at least a couple of weeks after the last frost. While eggplants thrive in hot, humid weather, an intense, sticky heatwave can reduce pollination.
They have a long growing season in much of the South, producing from July until October. In the Coastal South, you may be able to plant these in the garden from mid-spring until late summer. While eggplant is perennial in tropical climates, hot temperatures result in bitter-tasting fruit. In South Florida, eggplant is usually grown in fall and winter.
Watering
Though an eggplant may survive dry spells, it thrives with moisture. Mulch around your eggplants to conserve moisture in the soil. Water frequently until your transplants are established, then make sure your plants receive at least an inch of water a week—2 inches is preferable. When the plant is fruiting, consistent moisture is key. Water so that the soil is moist (but not soggy) at a depth of 6 inches. A soaker hose can be helpful for keeping your plants watered.
Soil
Eggplants like rich and loamy or sandy soil. Plant in fertile, well-drained soil amended with organic matter, such as composted manure or chopped leaves. The organic matter both enriches the soil and helps retain moisture. Eggplants prefer acidic soil but will do fine in neutral soil.
Fertilizing
Use an organic product, such as Jobe’s Organics Vegetable & Tomato (2-7-4), according to label directions. Fertilize at planting (unless you are using potting soil that contains fertilizer, in which case you should wait) and every four weeks. Over-fertilizing with nitrogen will result in bushy growth and fewer flowers.
Propagation
Eggplants can be propagated by cuttings. This is an easy way to obtain new plants and takes less time than growing them from seed. Take cuttings at the end of the growing season, around early fall, and plant them outdoors in the spring. To propagate:
- Use clean pruners to cut healthy 4- to 6-inch segments from the stems. Make sure each cutting has several leaf nodes. Remove leaves from the lower section.
- Put the cuttings in a jar filled with water and set it in a bright location with indirect light. Change the water every few days.
- Roots should begin to grow after two weeks.
- Plant the rooted cutting in a large pot filled with soil and water well.
- Keep the pot in bright light and water regularly to keep the soil evenly moist.
- In spring, as the weather warms, slowly acclimate the plant to the outdoors and transplant into the garden.
How To Grow From Seed
The most common way to grow eggplants is to start with seeds. Begin germination indoors about six weeks before the last frost:
- Fill 3-inch pots or a seed tray with sterile seed-starting mix and moisten.
- Sow your seeds 1/4 inch deep and 2 or 3 inches apart. Lightly cover with seed-starting mix and water. Cover the pots or tray with clear plastic to help maintain moisture.
- Place in bright light in a warm spot that is at least 70ºF and preferably 80ºF. Germination may improve with use of a heating mat under your pots.
- After seeds sprout, remove the clear plastic. Water to keep moist and provide very bright light for the best growth. A grow light helps plants develop strong, straight, healthy stems. Thin plants if they get overcrowded.
- Set your plants outdoors in a shady spot once daytime temperatures reach 70ºF, bringing plants indoors on cool nights. Gradually increase exposure to direct sunlight, then transplant 18-24 inches apart in the garden.
Potting and Repotting
Many eggplant varieties don’t grow taller than 2 or 3 feet, making them an excellent container plant for your patio or garden. Unless you use an undersized container, you’ll likely only pot your eggplant once in the growing season. Place one eggplant in a 12- to 14-inch container in high-quality potting soil, at the same depth as it was in its nursery pot. Or, use a 20-inch pot for up to three eggplants. Add a small tomato cage or stake your plants.
Use a balanced, slow-release fertilizer like Osmocote at the time of planting and water well. Water containers whenever the top inch of soil is dry.
Overwintering
In warm climates, eggplants can be grown as perennials. In this case, prune back the plant and the leaves will regrow in spring. Potted eggplants can be brought indoors in areas with freezing weather.
Pests and Diseases
Common Pests & Plant Diseases
Without a doubt, flea beetles will find your tasty crop, making pinholes in leaves that can do real damage to young plants. Deter their early-season arrival by shielding plants with row covers until they bloom (then remove them). Or use diatomaceous earth to dust leaves lightly. This organic pesticide works well, though it must be reapplied after a rainfall. Once the plants grow larger, they can tolerate considerably more damage from flea beetles.
Aphids, whiteflies, and spider mites pierce leaves to suck the sap. Spray aphids and spider mites with a strong stream of water to discourage them. Use insecticidal soap to control an infestation.
Colorado potato beetles, cutworms, and hornworms can cause significant defoliation on plants. Pick off these large insects and drop them in a can of soapy water. An insecticide containing spinosad can also be effective, but it should not be sprayed while bees are around.
Serious diseases like Verticillium wilt and bacterial wilt (sudden withering of the plant), Phytophthora blight (dark streaks on branches progressing to plant collapse), and southern blight (a white fungal infection that rots the stem) are spread among members of the nightshade family and remain in the soil. Once an infection appears, controlling it is very difficult. To reduce the likelihood of passing a disease to your eggplant, don’t plant where tomatoes, potatoes, or peppers grew in the past three years. Space rows of eggplant three feet apart to allow air circulation, and always water at the base of plants. Make sure to plant in well-drained soil and do not overwater.
Common Problems
Eggplant needs regular water and warm temperatures to produce healthy fruits that don’t taste bitter. Common problems that can affect the plants are often a result of the environment or care. Here’s what to look for:
Not Producing Fruit
Sometimes plants will bloom but fail to produce any fruit. The blooms drop because of a frigid night, a lack of water, or because the flowers were not pollinated. Eggplants are primarily wind-pollinated, so still days or very hot, sticky weather can prevent pollination from occurring. If this becomes a recurring problem, you can try gently shaking your plants each day or using a paintbrush to spread pollen among the flowers.
Leaves Turning Yellow
Overwatering and underwatering can both cause yellowing leaves. Make sure to give the eggplant plenty of moisture, about 1-2 inches per week. The top few inches of soil should be moist and not soggy.
III. Uses and Benefits
Culinary uses
Raw eggplant can have a bitter taste, with an astringent quality, but it becomes tender when cooked and develops a rich, complex flavor. Rinsing, draining, and salting the sliced fruit before cooking may remove the bitterness. The fruit is capable of absorbing cooking fats and sauces, which may enhance the flavor of eggplant dishes.
Eggplant is used in the cuisines of many countries. Due to its texture and bulk, it is sometimes used as a meat substitute in vegan and vegetarian cuisines. Eggplant flesh is smooth. Its numerous seeds are small, soft and edible, along with the rest of the fruit, and do not have to be removed. Its thin skin is also edible, and so it does not have to be peeled. However, the green part at the top, the calyx, does have to be removed when preparing an eggplant for cooking.
Eggplant can be steamed, stir-fried, pan fried, deep fried, barbecued, roasted, stewed, curried, or pickled. Many eggplant dishes are sauces made by mashing the cooked fruit. It can be stuffed. It is frequently, but not always, cooked with oil or fat.
- East Asia
Korean and Japanese eggplant varieties are typically thin-skinned.
In Chinese cuisine, eggplants are known as qiézi (茄子). They are often deep fried and made into dishes such as yúxiāng-qiézi (“fish fragrance eggplant”) or di sān xiān (“three earthen treasures”). Elsewhere in China, such as in Yunnan cuisine (in particular the cuisine of the Dai people) they are barbecued or roasted, then split and either eaten directly with garlic, chilli, oil and coriander, or the flesh is removed and pounded to a mash (typically with a wooden pestle and mortar) before being eaten with rice or other dishes.
In Japanese cuisine, eggplants are known as nasu or nasubi and use the same characters as Chinese (茄子). An example of it use is in the dish hasamiyaki (挟み焼き) in which slices of eggplant are grilled and filled with a meat stuffing. Eggplants also feature in several Japanese expression and proverbs, such as “Don’t feed autumn eggplant to your wife” (秋茄子は嫁に食わすな, akinasu wa yomi ni kuwasuna) (because their lack of seeds will reduce her fertility) and “Always listen to your parents” (親の意見と茄子の花は千に一つも無駄はない, oya no iken to nasu no hana wa sen ni hitotsu mo muda wa nai, literally: “not even one in a thousand of one’s parents’ opinions or the eggplant flowers is in vain”).
In Korean cuisine, eggplants are known as gaji (가지). They are steamed, stir-fried, or pan-fried and eaten as banchan (side dishes), such as namul, bokkeum, and jeon.
- Southeast Asia
In the Philippines, eggplants are of the long and slender purple variety. They are known as talong and are widely used in many stew and soup dishes, like pinakbet. However the most popular eggplant dish is tortang talong, an omelette made from grilling an eggplant, dipping it into beaten eggs, and pan-frying the mixture. The dish is characteristically served with the stalk attached. The dish has several variants, including rellenong talong which is stuffed with meat and vegetables. Eggplant can also be grilled, skinned and eaten as a salad called ensaladang talong. Another popular dish is adobong talong, which is diced eggplant prepared with vinegar, soy sauce, and garlic as an adobo.
- South Asia
Eggplant is widely used in its native India, for example in sambar (a tamarind lentil stew), dalma (a dal preparation with vegetables, native to Odisha), chutney, curry (vankai), and achaar (a pickled dish). Owing to its versatile nature and wide use in both everyday and festive Indian food, it is often described as the “king of vegetables”. Roasted, skinned, mashed, mixed with onions, tomatoes, and spices, and then slow cooked gives the South Asian dish baingan bharta or gojju, similar to salată de vinete in Romania. Another version of the dish, begun-pora (eggplant charred or burnt), is very popular in Bangladesh and the east Indian states of Odisha and West Bengal where the pulp of the vegetable is mixed with raw chopped shallot, green chilies, salt, fresh coriander, and mustard oil.
Sometimes fried tomatoes and deep-fried potatoes are also added, creating a dish called begun bhorta. In a dish from Maharashtra called bharli vangi, small brinjals are stuffed with ground coconut, peanuts, onions, tamarind, jaggery and masala spices, and then cooked in oil. Maharashtra and the adjacent state of Karnataka also have an eggplant-based vegetarian pilaf called ‘vangi bhat’.
- Middle East and the Mediterranean
Eggplant is often stewed, as in the French ratatouille, or deep-fried as in the Italian parmigiana di melanzane, the Turkish karnıyarık, or Turkish, Greek, and Levantine musakka/moussaka, and Middle Eastern and South Asian dishes. Eggplants can also be battered before deep-frying and served with a sauce made of tahini and tamarind. In Iranian cuisine, it is blended with whey as kashk e bademjan, tomatoes as mirza ghassemi, or made into stew as khoresht-e-bademjan. It can be sliced and deep-fried, then served with plain yogurt (optionally topped with a tomato and garlic sauce), such as in the Turkish dish patlıcan kızartması (meaning fried aubergines), or without yogurt, as in patlıcan şakşuka.
Perhaps the best-known Turkish eggplant dishes are imam bayıldı (vegetarian) and karnıyarık (with minced meat). It may also be roasted in its skin until charred, so the pulp can be removed and blended with other ingredients, such as lemon, tahini, and garlic, as in the Levantine baba ghanoush, Greek melitzanosalata, and Moroccan zaalouk. A mix of roasted eggplant, roasted red peppers, chopped onions, tomatoes, mushrooms, carrots, celery, and spices is called zacuscă in Romania, and ajvar or pinjur in the Balkans.
A Spanish dish called escalivada in Catalonia calls for strips of roasted aubergine, sweet pepper, onion, and tomato. In Andalusia, eggplant is mostly cooked thinly sliced, deep-fried in olive oil and served hot with honey (berenjenas a la Cordobesa). In the La Mancha region of central Spain, a small eggplant is pickled in vinegar, paprika, olive oil, and red peppers. The result is berenjena of Almagro, Ciudad Real. A Levantine specialty is makdous, another pickling of eggplants, stuffed with red peppers and walnuts in olive oil. Eggplant can be hollowed out and stuffed with meat, rice, or other fillings, and then baked. In Georgia, for example, it is fried and stuffed with walnut paste to make nigvziani badrijani.
The eggplant was brought to Europe through the Iberian Peninsula where it was consumed by Muslims and Sephardic Jews, and was relatively unknown in other parts of Europe (except southern Italy) perhaps as late as the 17th century. It is considered to this day one of the defining ingredients of Sephardic Jewish cuisine.
- Iran
In Iranian cuisine, eggplant (called bādenjān or bādemjān in Persian) can be used in both appetizers and main courses. It can also be pickled in vinegar. The ideal eggplant in Iranian cuisine is long, straight, firm, and black. Based on how al-Razi uses the color of eggplant as a shorthand for purpleness in his Kitab al-hawi, it can be assumed that the dark purple kind of eggplant was the widely grown variety in Iran at his time (9th century). Its importance in Iran is alluded to in the Ain-i-Akbari of Abu’l-Fazl ibn Mubarak, which says “this vegetable is on sale in the markets in Iran all the year round and in such abundance that it is sold for 1.5 dams per seer” (which was a cheap price at that time).
In Iran, unlike places like Greece, Turkey, and North Africa, eggplant is cooked peeled and usually seasoned with cinnamon or especially turmeric. Most eggplant dishes are classified as nankhoreshi (eaten with bread), and they are commonly served as snacks alongside alcoholic beverages.
The 14th-century poet Boshaq At’ema refers to an early eggplant dish called burani-e badenjan: chopped eggplant sautéed with onions and turmeric, then slowly cooked, and finally mixed with yogurt. The combination of eggplant and kashk (condensed whey) is popular in Iranian cuisine; it is found in dishes like kashk o badenjan as well as ash-e kashk o badenjan (involving layers of sautéed eggplant, grilled onions, and red beans topped by kashk seasoned with turmeric). Another eggplant dish is mast o badenjan, also known as nazkhatun in Tehran, which involves eggplant, yogurt, and dried mint. Eggplant can also be cooked in stews (khoreshes), either with lamb (khoresh-e badenjan) or with chicken and either unripe grapes or pomegranate juice (mosamma-ye badenjan). Variants of ab-gusht, eshkana, fesenjan, and kuku also make use of eggplant. Some regional dishes involving eggplant include badenjan-polow, a dish mainly from Fars and Kerman that combines white rice with a paste of chopped sautéed eggplant, chopped meat, and spices; as well as the northern Iranian badenjan-e qasemi, a casserole using grilled eggplant, garlic, tomatoes, and eggs.
Eggplants are traditionally among the foods that get preserved and stored for winter in Iran. They are selected in the last month of summer, when they are most readily available, then peeled, and finally preserved in one of two ways. In the first way, the peeled eggplants are cut, salted, and left to “sweat” (to make them less bilious); then they are sun-dried by hanging them on a line. The dried eggplants are then rehydrated 24 hours before being cooked. In the second way, the peeled eggplants are cooked in oil, put in a copper pot, and finally covered with plenty of hot oil, “which congeals to seal them”.
Medieval Iranian writers such as al-Razi and al-Biruni cautioned that eggplant contains harmful qualities, and it must be ripe and cooked before eating to neutralize them. They wrote that it could cause heat and dryness and an excess of black bile, contributing to a wide range of health problems. If the “salt” in it was removed, or it was cooked in oil or vinegar, then they wrote that eggplant gained healthy attributes. Present-day Iranian attitudes to the eggplant reflect this medical tradition’s influence: the eggplant is “considered rather dangerous… a cook in Tehran will say that the poison must be taken out”. People also use eggplant seeds as an expectorant to relieve asthma and catarrh.
IV. Harvesting and Storage
Look for glossy skin versus the dull skin of overripe, bitter eggplant. Clip the thick, woody stem with snips, and enjoy the fruit while fresh. Eggplants are chameleons in the kitchen and useful in many forms. Sliced or diced, they are great for grilling, perfect pureed, simple to stir-fry, and make a hearty addition to many Italian and Mediterranean dishes.
