Eggplant rounds out the nightshade trio with tomato and pepper, and it is the heat-lover of the three: give it real warmth and bright light and it produces for a long season, but a cold bench stops it cold.
What it wants
Eggplant wants the most warmth of the fruiting crops:
- Temperature, 70 to 85°F by day and 65 to 70°F at night. It is the most cold-sensitive of the nightshades, and a chill drops its flowers.
- Light, high: a DLI of 20 to 30 mol/m²/day for a good fruit set.
- Feeding, pH 5.5 to 6.5 and a strong EC of 2.5 to 3.5 mS/cm; it is a hungry plant.
- Humidity and air, moderate VPD with air movement; the flowers need shaking to set, like tomato.
- Roots, warm and stable; cold roots stall it as surely as cold air.
The arc
Eggplant follows pepper's patient calendar: six to eight weeks as a transplant, a slow climb to first fruit around two to three months in, then a long, productive run in steady warmth. Trained and pruned like its nightshade cousins, a single plant carries fruit for months once it gets going.
What it fears
Cold is the first enemy: below the high 50s the plant sulks and sheds blossoms, so warmth is non-negotiable. Pollination is the tomato problem again, because eggplant flowers need vibration to release pollen, which means a daily shake or a pollination wand indoors. Spider mites, thrips, and aphids all favor the broad leaves, so watch the undersides.
Getting it right
Keep it genuinely warm day and night, feed it hard, and give the flowers a daily shake to set fruit. Be patient through the slow start, the way you are with peppers. The cultivar browser spans classic globe types to slim Asian ones, and a pollination aid plus steady warmth carries the fruit set. Track first-fruit timing against your night temperatures and the pattern will tell you your room.
Tools for this crop
Frequently asked questions.
What temperature does eggplant need?
Eggplant is the warmest-loving of the nightshades: 70 to 85°F by day and 65 to 70°F at night. It is more cold-sensitive than tomato or pepper, and temperatures in the 50s make it drop its blossoms and stall. Steady warmth day and night is the single most important thing you give it.
Do I need to pollinate eggplant indoors?
Yes. Eggplant flowers self-pollinate but need vibration to release the pollen, just like tomatoes, so indoors you supply the movement: a daily gentle shake of the flowering stems, an electric pollination wand, or a fan. Without it the flowers often drop instead of setting fruit.
Why are my eggplant flowers falling off?
Blossom drop in eggplant is usually cold, heat, or a lack of pollination. Nights below the high 50s, days that are too hot, or flowers that never got their pollen shaken loose all end the same way. Hold steady warmth and shake or otherwise pollinate the flowers daily during the set.