Watermelon should be ready to harvest this month. Check for size and colour.
Growing Calendar
This month: Sep
Log to journalReady to harvest now
- •Check size and ripeness
- •Harvest regularly
- •Store or use fresh
Watch Out For
The UK growing season is genuinely marginal for watermelon: even with care, some years won't produce ripe fruit; treat it as an ambitious, fun project rather than a reliable crop
Powdery mildew and red spider mite build up fast in the hot, dry conditions the plant needs: check leaves regularly and improve airflow
Fruits need consistent warmth to ripen: a poor late summer can leave watermelons large but bland and underripe
Grown Organically
Every method in this guide works with natural systems: no synthetic chemicals, no shortcuts.
Read our approachCommon Questions
About growing Watermelon in the UK
Can watermelon really be grown in the UK?
Yes, but it's genuinely the most challenging common fruit to ripen in a UK climate. Success is far more likely in a greenhouse or polytunnel, with a compact early variety like 'Sugar Baby', and in a warm summer. Treat it as an ambitious project rather than a guaranteed harvest.
How do I know when a watermelon is ripe?
Look at the curly tendril nearest the fruit's stem: it turns brown and dry when the melon is ripe. The underside resting on the ground should turn from white to a pale yellow (the 'ground spot'), and a ripe fruit sounds hollow when tapped.
Why is my watermelon plant not producing fruit?
Usually poor pollination in cool, wet weather, or too much nitrogen feeding producing lush leaves at the expense of flowers. Hand-pollinate female flowers (small round swelling behind the petals) with a male flower each morning, and switch to a high-potassium feed once flowering starts.
How many watermelons will one plant produce?
In a UK garden, 2–3 fruits per plant is a realistic, good outcome; large American varieties may only manage one. Compact varieties bred for shorter seasons are far more likely to ripen multiple fruit before autumn.
Written from real growing experience, not just research. Read the story behind Pelham Gardens.
Member guides
There's more to growing Watermelon than this guide covers.
A Garden Journal to log what worked, a personalised sowing planner in My Garden, and monthly reminders timed to the calendar.
