Allotments 4 All

When is it time ti sow courgette,cucumber & tomato's in an unheated greenhouse ???

For outdoor or indoor planting??
On heat or not??

6 weeks before last frost for an unheated greenhouse.  Last frost date

http://www.gardenaction.co.uk/main/weather.asp

In case my thing was misunderstood, I'm about to sow my cus & toms on heat for planting in an unheated 'house in May. Courgettes get sown about mid-April for planting outside late May with cover.

thanks all ;D