Chilli pepper: flowers dropping without setting fruit

What it is likely to be on chilli pepper

1. Blossom drop

   Candidate 1very common on this plant

   ·source

   Sourced guidancehigh confidence

   • University of Minnesota Extension — University of Minnesota: Tomato — blossom drop

   Checked 2026-08-13

   Open flowers dropping from the plant without setting fruit, leaving a bare stalk. In tomatoes, peppers and chillies it is almost always temperature: pollen is sterile above roughly 30 °C and below roughly 13 °C, so the flower opens, fails to pollinate and is shed. It is a fault in the conditions rather than in the plant.

   Points towards it

   • · pollen is sterile above roughly 30 °C and below roughly 13 °C, so a temperature extreme while the flowers were open is the direct cause
   • · an unventilated greenhouse reaches the sterilising temperature far more readily

   Argues against it

   • · the compost is dry, and a plant short of water sheds flowers for that reason instead — the fix is different

   Check this next

   Match the drop against the weather over the previous week. Blossom drop follows a hot spell or a cold snap by a few days and stops when temperatures settle, which no nutritional cause does.

   What to do now

   Ventilate and shade under glass, or delay planting out until nights are reliably warm. Nothing applied to the plant will fix this — later trusses set normally once conditions settle. Tapping the trusses at midday helps where still air rather than temperature is the limit.

   ·source

   Sourced guidancehigh confidence

   • University of Minnesota Extension — University of Minnesota: Tomato — blossom drop

   Checked 2026-08-13

2. Underwatering

   Candidate 2common on this plant

   ·source

   Sourced guidancemoderate confidence

   • Royal Horticultural Society: Watering

   Checked 2026-08-13

   Easier to correct than overwatering and easily confused with it, because a plant short of water and a plant drowning both wilt. The distinguishing observation is not the plant at all — it is the compost, and it takes two seconds to check.

   Points towards it

   • · the compost is dry, and a plant short of water sheds flowers first
   • · water shortage affects the whole plant

   Argues against it

   • · the compost is wet, so water shortage is not the reason the flowers are dropping — this rules it out entirely.

   Check this next

   Check the compost at depth before blaming the weather. A plant dropping flowers with dry compost and some wilting is short of water; one dropping them with moist compost after a hot week is not.

   What to do now

   Water thoroughly and keep it even. Flowers are shed before leaves when a fruiting plant runs short, so this is an early warning rather than a late one.

   ·source

   Sourced guidancehigh confidence

   • Royal Horticultural Society: Watering

   Checked 2026-08-13

Narrow it down

This page lists everything at once, which is the right shape for reading and the wrong shape for deciding. The interactive tool asks one question at a time, starting with whichever would separate these causes fastest, and stops as soon as further answers would not help.

Opens with the plant and the symptom already set. Nothing you answer is stored or sent anywhere — the answers live in the address bar and nowhere else.

What this does not cover

These are the causes GrowingHQ holds rules for on chilli pepper — not every cause there is. Where several problems look alike, the honest answer is often that they cannot be told apart by eye, and a page that named one would be guessing. If none of the above fits, the general flowers dropping without setting fruit page lists causes across all plants, and the Chilli pepper profile lists the problems it is prone to.