How to grow aubergines

Aubergine seeds are widely available in garden centres and from online seed suppliers. Be sure to buy early though, so you’re ready to sow in late winter or early spring, and make sure you have a warm space to germinate and grow these tender plants. 

If you don’t have the time or space to grow from seed indoors, you can buy plug plants and young plants from many gardening retailers in spring and early summer, although the choice of varieties will be more limited. Grafted aubergine plants are also available, mainly from online suppliers – these are more expensive, but are more vigorous, robust plants that should cope better with cooler conditions outdoors, producing a larger crop.

Water aubergine plants generously and consistently throughout the growing season. Plants in containers are particularly susceptible to drying out and may need watering at least once a day in hot weather. An automated drip irrigation system may be useful to ensure consistent watering.

Also, mist the leaves regularly (ideally twice daily) with tepid water to discourage red spider mites and improve fruiting. Or, on hot days, damp down the greenhouse in the morning by pouring a full watering can over the paved floor, so it evaporates during the day, raising the humidity.

Apply a thick layer of mulch, such as well-rotted manure or garden compost, around aubergine plants to help hold moisture in the soil and deter weeds.

Once the first flowers appear, give aubergine plants a high potassium liquid fertiliser, such as tomato feed, every two weeks, to encourage flowering and fruiting.

When aubergine plants are 30cm (1ft) tall, pinch out the tip of the main stem to encourage side-shoots. This creates bushier plants that should produce more fruits. 

Aubergines can form large, top-heavy plants, so insert a sturdy bamboo cane once they are in their final container and tie in the main stem as it grows. You may need to add more canes to support the side-shoots once fruits start to form, particularly if you have a heavy crop or large fruits. 

To ensure successful pollination in a greenhouse or coldframe, open the door and vents on warm days when plants are in flower, to help insect pollinators reach them. Misting the flowers also aids self-pollination, or you can hand pollinate with an artist’s paintbrush.

With larger-fruited varieties, once five or six fruits have started to form, remove any further flowers. Varieties with small fruits can be allowed to produce many more.

To encourage fruits to ripen towards the end of the season, remove any new fruits that start to form after late summer, as they are unlikely to ripen. With outdoor plants, protect them with a plastic-free crop cover if the fruits aren’t ripe by late September, or move potted plants indoors if possible before overnight temperatures drop.