Melon: flowers dropping without setting fruit

What it is likely to be on melon

1. Poor fruit set

   Candidate 1common on this plant

   ·source

   Sourced guidancehigh confidence

   • Royal Horticultural Society: Melons — growing under glass
   • Penn State Extension — Pennsylvania State University: Strawberry pollination and misshapen fruit

   Checked 2026-08-13

   A plant that flowers freely and sets little or no fruit. It is the commonest disappointment in fruit growing and it has four quite different causes, only one of which is the plant's fault. Working out which applies is the difference between fixing it and replacing a healthy tree.

   Points towards it

   • · a closed greenhouse or tunnel keeps out the insects the flowers depend on, which is the whole mechanism
   • · no pollinator reaches any of the flowers, so none of them set
   • · healthy plants flowering freely and setting nothing points away from stress

   Argues against it

   • · cold during flowering stops the fruit setting whether or not a pollinator arrived, and is the better explanation when it applies

   Check this next

   Count the flowers and look for insects at midday. Under cover with the vents shut and no bees working, pollination is the first candidate — and on a strawberry it shows in the shape rather than the count, because a partly pollinated fruit swells only where the seeds were fertilised and comes out hard, green and cat-faced on the other side. On a melon, check that female flowers with the tiny swelling behind them are present at all; a plant carrying only males has nothing to set yet.

   What to do now

   Open the vents and doors on warm days so insects can get in, which fixes it for the rest of the season with no further work. Where that is not practical, transfer pollen with a soft brush around midday when the flowers are dry — on a melon, from an open male flower into each female; on strawberries, a light brush over each open flower every couple of days through the flowering period.

   ·source

   Sourced guidancehigh confidence

   • Royal Horticultural Society: Hand pollination

   Checked 2026-08-13

2. Cold damage

   Candidate 2common on this plant

   ·source

   Sourced guidancehigh confidence

   • Royal Horticultural Society: Strawberries — frost damage
   • University of Minnesota Extension — University of Minnesota: Strawberry frost protection

   Checked 2026-08-13

   Blackened, translucent or limp tissue appearing suddenly after a cold night or a spell beside a draught. Tender plants show it well above freezing — basil blackens around 10 °C — so 'there has been no frost' does not rule it out.

   Points towards it

   • · an open strawberry flower is killed at around −2°C, and early flowers are exposed
   • · cold air pools, so a bed can be frosted at one end and untouched at the other, and cloched rows escape

   Argues against it

   • · there was no frost, so this is not the explanation — this rules it out entirely.

   Check this next

   Look into the middle of a failed flower. A frosted strawberry flower has a distinctly black centre against white petals — the 'black eye' — and it is unmistakable once seen. Poor pollination leaves the centre yellow and normal and shows up later in the fruit's shape instead. On a melon, cold shows as flowers and tiny fruitlets yellowing and shrivelling at the stalk after a run of cold nights rather than as anything visible in the flower itself.

   What to do now

   Cover strawberries with fleece overnight when frost is forecast during flowering and take it off by day so insects can work the flowers. Later flowers on the same plants set normally and still crop, so do not dig anything up. For melons, keep night temperatures up under cover and hold off planting out until the nights are reliably mild.

   ·source

   Sourced guidancehigh confidence

   • Royal Horticultural Society: Frost damage — protection

   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 melon — 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 Melon profile lists the problems it is prone to.