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Aubergine

A long hot season gives glossy fruit for months, and Portugal has exactly that season.

1. Sow indoors 8 to 10 weeks before your last frost, 0.5 cm deep, at 25 to 28 C. It will not germinate cold.
2. Prick out into 9 cm pots at the first true leaf.
3. Harden off over 10 days once nights stay above 12 C.
4. Plant out 50 cm apart into warm soil, or into a greenhouse or a large pot.
5. Stake each plant, a loaded aubergine snaps at the fork.
6. Pinch the growing tip at 40 cm to make it branch, and keep 4 to 6 fruits per plant.
7. Feed high potash weekly once the first fruit sets.
8. Cut fruit with secateurs while the skin is still glossy.

Soil

Rich, free-draining soil with plenty of compost, pH 6.0 to 6.8.

Sun

Full sun, 8 hours. It wants 22 to 30 C to set fruit.

Water

25 mm a week, more in heat. Water the soil, not the leaves.

Spacing

50 cm apart, rows 70 cm

Depth

Sow 0.5 cm deep

Care

['Mulch 5 cm with straw, it hates hot dry roots.', 'Mist or tap the flowers in still greenhouse air to help them set.', 'Remove the lowest leaves once fruit is setting, for airflow.', 'Do not let it carry ten fruits, the plant stalls and none of them size up.']

Harvesting

Pick when the skin is shiny and springs back slowly to a thumb press. Dull skin means over-ripe and bitter with hard seed. Always cut, never pull, the calyx is prickly and the stem is woody.

Storing

1 week at 10 to 12 C, not in the fridge, cold damages the flesh. Slice and freeze after cooking, or dry slices for winter. Preserving in oil needs an acidified recipe, follow a tested one.

Grow it next to

Beans, marigolds, peppers and basil. Do not follow tomatoes or potatoes in the same bed.

Problems

[{'cause': 'Nights below 15 C or days above 35 C', 'fix': 'Plant out later into warm soil, shade at midday in extreme heat, and tap flowers to pollinate.', 'symptom': 'Flowers drop without setting fruit'}, {'cause': 'Red spider mite in hot dry air', 'fix': 'Raise humidity by damping the floor, and hose leaf undersides twice a week.', 'symptom': 'Fine webbing and speckled pale leaves'}, {'cause': 'Picked too late', 'fix': "Pick while glossy, usually at two thirds of the variety's full size.", 'symptom': 'Fruit bitter with hard brown seeds'}, {'cause': 'Colorado beetle or flea beetle', 'fix': 'Hand-pick beetles and larvae, and mesh young plants.', 'symptom': 'Leaves stripped to skeletons'}, {'cause': 'Blossom end rot from irregular watering', 'fix': 'Water evenly and mulch. It is a water problem, not a calcium shortage in most soils.', 'symptom': 'Sunken dark patch on the fruit base'}]

Saving your own seed

Let one fruit go dull and yellow-brown on the plant, scoop out the seed, rinse and dry a week. Mostly self-pollinating but insects do cross it, so separate varieties by 15 m.

Containers

Very good in a 25 to 30 litre pot, one plant per pot, in the hottest spot you have. A pot warms faster than open ground, which suits it.