GreenlyWhen to plant watermelon in Glasgow
In Glasgow, watermelon: sow seedlings around 29 May for the greenhouse and around 19 June for open ground; plant into a greenhouse around 30 June; plant out into open ground around 21 July.
Last spring frost around 28 April, first autumn frost around 11 November. Frost-free days: 197 days.
The dates follow the Greenly calendar: open ground a week after the last frost once the soil is warm enough for the crop, frost-hardy crops three weeks before it, an unheated greenhouse three weeks earlier, seedlings sown so they are ready on the day. In a cold year allow a week or two more.