Temperature Requirements
- Tomato: 20–27°C for vegetative growth, 18–24°C for fruit set.
- Brinjal: 25–30°C optimum for growth.
- Chilli: 20–30°C optimum; fruit set reduces above 32°C.
- Okra: 25–35°C optimum; sensitive to frost.
- Potato: 15–20°C for tuberization; 20–25°C for vegetative growth.
- Onion: 13–24°C optimum for bulb formation; long-day crop.
- Cabbage & Cauliflower: 15–20°C for head initiation.
- Pea: 10–25°C; frost-sensitive.
- Cucumber: 25–30°C; day-neutral crop.
- Pumpkin: 20–35°C optimum; sensitive to frost.
Photoperiod & Light
- Onion & garlic – long-day crops; require 12–14 h light for bulb formation.
- Tomato, brinjal, chilli – day-neutral crops; flowering not affected by day length.
- Cauliflower – short-day crop (requires 10–12 h light) for curd formation.
- Pea – long-day plant for flowering.
- Lettuce – long-day crop for bolting.
Soil & Moisture Requirements
- Tomato: well-drained sandy loam, pH 6–7.
- Brinjal: deep, fertile loamy soil with pH 6–7.
- Potato: light loam to sandy loam; pH 5–6.5.
- Onion & garlic: well-drained sandy loam, rich in organic matter.
- Cabbage & cauliflower: fertile loam with high organic matter; pH 6–7.
- Okra: well-drained sandy loam; tolerant to drought.
- Pea: light loam, rich in organic matter; pH 6–7.
- Cucumber & other cucurbits: well-drained, fertile sandy loam.
- Pumpkin & squash: light loam with high organic matter.
- Bitter gourd: sandy loam, well-drained; pH 6–7.
Water & Irrigation
- Tomato: 5–6 irrigations during crop season; avoid waterlogging.
- Potato: 7–8 irrigations; critical during tuber initiation.
- Cabbage & cauliflower: frequent irrigation required during head initiation.
- Okra: tolerant to drought; irrigation improves yield.
- Onion: regular irrigation needed for uniform bulb formation.
- Pea: irrigation critical during flowering and pod formation.
- Cucurbits: 6–8 irrigations; avoid waterlogging to prevent downy mildew.
- Mulching reduces soil evaporation and conserves moisture.
Temperature/Environmental Stress Effects
- High temperature in tomato (>32°C) – reduces fruit set.
- Low temperature in tomato (<15°C) – causes blossom drop.
- Frost in potato – damages tubers and leaves.
- Heat stress in chilli – reduces flower retention.
- High humidity in tomato and cucurbits – favors fungal diseases.
- Water stress – reduces leaf expansion and fruit size.
- Excess nitrogen – causes excess vegetative growth, reduces fruiting.
- Calcium deficiency – causes blossom end rot in tomato and chilli.
- Boron deficiency – causes hollow stem in cauliflower and broccoli.
- Mulching reduces temperature fluctuations and conserves moisture.
