Growing eggplant (Solanum melongena) is a great choice for a number of reasons. These stately plants add elegance to both vegetable and ornamental borders. Ideal for gardens that enjoy long, warm summers these versatile plants thrive in both raised beds and containers. A member of the nightshade family, the eggplant is closely related to the vegetable gardener’s favorite, the tomato plant.
People have been growing eggplant for over 1500 years. Originating in China and India the plant was exported along the trade routes into Europe and Africa before being taken onto the New World by Spanish explorers during the 1800s.
Also known as aubergines, these are pleasingly reliable annual plants. Just make sure that they get the sun and warm temperatures that they crave. Gardeners in cooler climates will enjoy success by growing fast maturing varieties or by cultivating the plants undercover, such as in a temperature controlled greenhouse.
Whether you are an experienced gardener or a complete beginner, this guide will take you through everything you need to know about growing eggplant.
Shiny and glossy, the aubergine is an elegant addition to the vegetable garden.
Different Varieties of Eggplant
Before you begin growing your own eggplant, you must first select a variety that not only appeals to your taste but is also suitable to your growing conditions. Most varieties are ready for harvesting around 70 to 90 days after transplanting.
Melongena is the most common eggplant genus. These plants typically produce dark purple pear shaped fruit that is 6 to 9 inches long. Within this genus Black Bell, Black Magic and Black Beauty are all reliable cultivars.
Other eggplant varieties are divided into cultivars. The most common are:
- Italian cultivars, these tend to produce oval fruit with rich mauve-purple skin.
- Indian cultivars are small, rarely more than a few inches long and oval or round. They have the typical dark purple aubergine skin.
- Chinese varieties tend to be rounder and are also purple.
- Japanese cultivars produce dark purple fruit that is typically smaller and more tender than the Chinese varieties.
Ichiban, a Japanese cultivar, is a reliable variety that does particularly well in containers. It produces, flavorsome, tender fruit which does not require peeling.
If you want something a little different, a number of plants produce white fruit. Common white varieties include White Beauty and Albino. These have smooth skin and tend to be thinner and longer than the more oval shaped Italian cultivars. Sicilian is another small plant, also known as Zebra or Graffitis its fruit is streaked purple and white.
If you are new to growing eggplants, try growing small fruiting varieties. Many people find these easier to successfully cultivate than the larger varieties. While the fruit is smaller, the crop is often heavier. Each plant can produce at least a dozen fruit. Patio Baby is a reliable compact variety that is easy to cultivate.
One of the most popular small varieties is Easter Egg. Rarely exceeding 12 inches in height the plant produces small, egg sized white fruit. Mini Bambino is another reliable miniature variety.
In addition to the typical dark purple varieties, aubergines also come in shades of white or streaked.This adds to their interest both in the garden and on the plate.
If you want to save some of the seeds for sowing next year, don’t choose a hybrid cultivar. These will not produce fruit that is true to type, if they produce fruit at all.
Finally, if you want to grow more than one variety, space them out throughout your garden. This helps to reduce the chances of cross pollination.
You can either purchase eggplant transplants, these are young plants ready for planting out in the garden, or start growing from seed. While this is more affordable, and offers you access to a wider variety of plants, growing from seed can also take longer.
Growing from Seed
Start your seeds 4 to 6 weeks before your last predicted frost date.
Before sowing, soak the seeds overnight in warm water. This helps to soften the shells, making germination easier.
Start inside undercover, the soil temperature must be between 75 and 85 ℉ for germination to occur. A heating mat, such as the VIVOSUN Seedling Heat Mat is a good way to regulate temperatures.
Sow the seeds as thinly as possible in pots or trays filled with fresh, moist potting soil. Cover the seeds with a thin layer of potting soil.
In ideal conditions germination usually occurs within 3 weeks. In slightly cooler temperatures this process may take a little longer.
Following germination thin the seedlings out to 2 to 3 inches apart. Allow the seedlings to grow on, keeping them warm and the soil moist. Two weeks after germination apply a dose of balanced fertilizer diluted to a ratio of 1 tablespoon of fertilizer per 1 gallon of water.
When spring temperatures consistently exceed 50 ℉ harden off your seedlings before transplanting outside.
Finding the Ideal Eggplant Growing Location
Aubergines are hot weather vegetables. Plant them in a full sun position for the best results.
When selecting your growing position you will need to be mindful of both soil and air temperatures if you want the plants to thrive. For optimal fruit production these plants require nighttime temperatures to be around 70 ℉ for at least two months. A soil thermometer is a useful investment. The Luster Leaf Digital Thermometer provides a durable, easy to use way to monitor the temperature of your soil.
If you are in a cooler area, try growing in containers in a greenhouse. Remember to allow pollinators access in the daytime to encourage propagation.
The soil should be fertile and well-draining. If your soil is lacking in nutrients, a soil test kit will tell you, work in amendments before planting. Well- aged compost or rotting manure are both ideal options if you need to organically enrich your soil. The soil pH level should be 5.5 to 7.0, a neutral to acidic profile. There are a number of ways to easily increase your soils acidity levels if it is too alkaline.
Dig and prepare your soil at least 2 weeks before planting. This gives the soil time to re-settle before you introduce your growing eggplant.
You can also plant your eggplant transplants in raised beds or containers filled with rich compost and organic soil.
Plant in an open, full sun position to ensure a large, healthy harvest.
How to Plant
Dig a hole in the prepared soil large enough to hold the transplant. Carefully remove the plant from its current container and position in the hole. The top of the root system should sit just below soil level. If your soil is not well-draining, try mounding the soil up and planting on top of the mound. This encourages excess moisture to drain away from the plant.
When you are happy with the position of the plant, backfill the hole with a mixture of soil, compost and a sprinkling of granular fertilizer. Firm the soil down and water well.
Space your transplants roughly 18 inches apart. If you are planting in rows, space the rows 24 to 36 inches apart. This gives the plants lots of growing room.
If, after planting, you are concerned about unexpected cold weather affecting your plants, try placing row covers over the transplants. Flarmor Floating Row Covers are a useful way to protect plants from cool weather and maintain soil temperature. Just make sure that the ends are open so that pollinators can reach the flowers.
Planting in Containers
Smaller or compact cultivars, such as Fairytale and Bambino are ideal for container growing. White eggplant cultivars also suit these conditions particularly well.
Your chosen container should be large enough to support not only the top heavy plant but also its extensive root system. A pot with a 5 gallon capacity that is 12 to 14 inches wide is ideal. In larger 20 inch pots you can plant up to 2 aubergines. Make sure your pot is clean and has lots of drainage holes in the bottom.
If you are growing in a cooler climate try growing in a large, dark container. Darker colors help to trap heat in the soil, keeping your plants warm, better than lighter pots.
Fill the pot with a rich, well draining potting medium. A mix that is two parts good quality potting soil to one part sand is ideal.
Make a hole in the soil large enough to hold your plant. Before adding the plant, place a handful of slow release fertilizer into the hole. Plant as described above. After planting gently firm down the soil and water well.
Supporting your Growing Eggplants
After planting remember to stake your plants. This helps to keep them upright. The eggplant, particularly when bearing fruit, can be top heavy and prone to toppling over. A secure stake or trellis helps the plants to stay upright.
Caring for a Growing Eggplant
As long as you can keep the plants warm enough then the eggplant is pleasingly easy to grow. Placing a layer of organic mulch around the plants helps to keep the soil moist and warm. It also prevents weeds from emerging. Mulch when your plants exceed 6 inches in height.
Watering your Plants
Water the plants regularly, especially when they are young. Water deeply to encourage a robust root system to develop.
When watering, water only the soil. Try to keep the foliage as dry as you possibly can. Do not water from overhead. This helps to keep the foliage free from mold and fungal issues.
Aim to keep the soil evenly moist. Don’t allow the soil to dry out. This can cause the fruit to be underdeveloped and bitter.
Once established you may only need to water if it hasn’t rained during the week. The plants should receive about an inch of water a week but this can be increased a little during particularly warm periods.
Fertilizing a Growing Eggplant
You will need to regularly fertilize your growing plants.
Apply a balanced fertilizer periodically throughout the growing season. Avoid fertilizers with a high nitrogen content, these can encourage foliage production at the expense of the fruit. Alternatively you can apply a slow release fertilizer.
Regularly water and fertilize your plants to help sustain healthy growth. Regular applications of fertilizer also help to promote larger fruit.
Liquid fertilizers, or diluted manure teas are easily incorporated into a watering routine. Alternatively granular fertilizers can be applied as a side dressing. Make sure you work the granular fertilizer into the soil.
Container plants in particular need regular fertilizing. But be wary of salt buildup in the soil. This can stunt growth. Fish or kelp based organic fertilizers are less likely to cause salt build ups in the soil. Alternatively flush the soil out every few weeks by watering well.
If the plant is struggling, dilute a liquid fertilizer and water it onto the plant, allowing the foliage to absorb the nutrients. Known as foliar feeding this is best done early in the day to give the plant time to dry out.
Pruning and Weeding
The growing eggplant requires minimal pruning. The first set of flowers can be pinched off to encourage more fruiting branches to form. Pinching out early flowers also encourages larger fruit to form later on.
You may need to lightly prune the foliage to help promote healthy air circulation around the plants.
Weed the soil regularly to ensure that it remains clear and healthy. There are a number of tools you can use to weed your soil without damaging the root system of your growing plants. An organic mulch such as grass clippings can also be used to deter weed growth.
Planting herbs such as thyme and French tarragon nearby helps to repel pests. Similarly Mexican marigolds repel beetles. However they are toxic to bean plants, so you will have to choose between the two.
The Mexican Marigold is a great companion plant. Not only does it repel pests but also attracts pollinators to your flowers.
Beans and other legumes such as peas are useful companion plants because they fix nitrogen in the soil. While too much nitrogen can be detrimental, some nitrogen in the soil is key to sustaining growing eggplants. Grow your eggplant either alongside legumes or in the same soil year after if you are following a crop rotation system.
Bush beans repel pests such as the Colorado potato beetle, which can be particularly destructive to the eggplant. If you are companion planting with beans or peas, plant the legumes at the back of the bed, where they can be supported by trellising. The eggplant can then be placed at the front of the bed where it can bask in the sun.
Potatoes and spinach plants are reliable companion plant choices as are peppers and tomatoes. These both share similar growing needs. Be careful when planting this combination, as well as sharing similar growing needs they are also all susceptible to the same pests and diseases.
Common Eggplant Problems and How to Prevent Them
Crop rotation helps to keep your soil and growing crops healthy. Rotate the plants every year, ensuring your eggplant crop is either planted with or immediately follows legumes around your garden. This is a guide to a simple crop rotation system if you wish to implement one in your garden.
Spacing your plants out correctly when planting and caring correctly for them also helps to ensure problems are kept to a minimum.
Try to keep your eggplant crop as warm as possible. Mulch the soil and use row covers or horticultural fleeces to protect them against unexpected cold spells. Row covers and plant collars can also be used to deter pests such as lace bugs and aphids.
Other common pests include:
- Flea beetles
- Tomato hornworms
Regularly inspect the foliage for signs of infestation. Insecticidal soap, which is easily made at home, can be used to treat most infestations. Large or stubborn infestations may require more than one treatment.
Crop rotation and encouraging natural predators such as ladybugs with a bug hotel also helps to reduce pest problems.
Allowing the soil to dry out and not watering frequently, can stress your plants and cause foliage to yellow. It can also impact negatively on fruit production.
Regularly check the foliage for signs of infestation. If spotted early enough infestations are easily treated.
Verticillium wilt is the most common issue. A deadly condition, it is caused by soil borne infections which stunts growth and cause plants to yellow and fail. Resistant cultivars are now available.
Another common problem encountered by eggplant growers is blossom end rot. This can be caused by overwatering or planting in poorly draining soil. Working calcium rich amendments such as bone meal or eggshells into the soil can help to prevent the problem.
Other common diseases include:
- Bacterial wilt, which causes plants to yellow and droop
- Southern blight, a nasty disease caused by a fungus that softens the root and crown
- Phomopsis blight which causes fruit to soften and foliage to gray or develop brown spots
- Phytophthora blight, destroys crops quickly causing dark streaks to form before the plant fails completely.
Adopting good growing practices and a simple crop rotation system can help to prevent most of these issues.
Do I Need to Hand Pollinate My Eggplant?
These plants are easily pollinated by the gentlest of breezes. You can also encourage pollination by planting pollinator attractive flowers close by as companion plants. However, there may still be occasions where you need to hand pollinate your flowers.
There are two types of fruiting plant: perfect plants and imperfect plants. Perfect plants produce flowers that contain both male and female parts. This means that the flower contains everything that it needs to produce fruit. They are also known as complete or bisexual flowers. Watermelons, cucumbers and zucchini all produce perfect flowers. Imperfect plants produce either male or female flowers. These require cross pollination from the male to the female flower before fruit can be produced.
Aubergines produce perfect flowers, meaning that hand pollination is a simple process.
The eggplant produces perfect flowers that contain both the pollen producing anthers and the pollen receiving pistills. This means that hand pollination is straightforward. Simply lightly tap the flowers when they are in full bloom. This will be at some point in mid to late summer, usually around 80 days after germination.
Tapping the flower should be enough to move the pollen around the flower, helping to pollinate the bloom. You can also use a delicate brush, such as a makeup brush or cotton swab to move the pollen around the flower. Hand pollination is often more successful if done in the morning when the flower is fully open.
Harvesting Your Fruit
The fruit of the eggplant are ready to harvest when their skin takes on a highly glossy appearance. Press the skin, if the indentation remains, and doesn’t spring back, it is ready to harvest. Use garden scissors to cut the fruit away from the plant, keeping the cap and about 1 inch of stem intact.
Be careful when harvesting, the stems and cap of some varieties can be lined with small prickles. These can irritate sensitive skins. If you are concerned, wear a pair of gloves when harvesting the fruit.
If you open the fruit to find brown seeds, it may mean the fruit is bitter and past its best. To prevent this issue some gardeners like to harvest the growing fruit when it is slightly young and just approaching its full, mature size.
Harvested fruit keeps for about 2 weeks in a refrigerator.
Saving the Seeds
You can only save seeds from open pollinated plants. Hybrid eggplant seeds may not germinate. If they do grow and produce it will likely be disappointing and not true to type.
To harvest ripe seeds allow an eggplant to remain on the plant so that it becomes overripe and inedible. Purple fruit turns brown when overripe, white and green varieties take on a yellow shade. It will also be shriveled and hard.
When the fruit is overripe, harvest and cut it open. Pick out the seeds and wash them in a bowl of water, cleaning away the pulp.
Spread the clean seeds out to dry on a tray in a cool position away from the sun. The humidity levels should be between 20 and 40 %. Drying the seeds can take 2 to 4 weeks.
Ensure the seeds are fully dry before storing in an airtight jar. If moisture builds up in the jar it means that the seeds are too wet. Add Silica Gel packets or another desiccant to save the seeds.
While the seeds can be stored for a period, they are best used as quickly as possible. The older the seeds are, the less viable they become.
Reliable and robust, the aubergine is a distinctive addition to any garden.
Growing eggplant can be a tricky process but if you can maintain an even temperature it is a hugely rewarding process. An elegant plant, the range of cultivars, and different colored fruit available, means that they are a great way to introduce color, structure and texture to a summer vegetable garden.