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FruitsTenderAnnual
Watermelon
Watermelon is a strongly heat-demanding cucurbit grown for large juicy fruits with crisp sweet flesh. It is most realistic as a protected crop in cooler climates, where warmth can be maintained for long enough to set and ripen fruit properly.
Basic information
Category
Fruits
Lifecycle
Annual
Hardiness
Tender
Planting partners
1 companion · 1 crop to avoid
Growth profile
Days to harvest
100 days
Germination window
4–10 days
Germination temperature
24–30 °C
Plant spacing
120 cm
Row spacing
180 cm
Sowing depth
2.5 cm
Height
30 cm
Spread
120 cm
Calendar
JJan
FFeb
MMar
AApr
MMay
JJun
JJul
AAug
SSep
OOct
NNov
DDec
Sow Indoors
Sow Outdoors
Plant Out
Flowering / Harvest
Timings based on average frost dates in the UK. Sign up to set your frost dates.
Care tips
Use the hottest site or greenhouse space available, and keep plants growing hard from the start with warmth, feeding and steady moisture. Support fruits if vines are trained upward, avoid repeated drought stress, and reduce watering slightly only once fruits are nearly mature to concentrate flavour.
Common pests
Aphids, red spider mite, powdery mildew, slugs.
