Posted: 22/03/2012 at 19:05
Hello Daisy Cottage
I would say it depends on where you live, and when you are likely to get your last frost? Greenhouses, if unheated, can get very chilly over night, so if it were me I'd wait another month, and then try putting in just one or two seedlings of each variety to begin with and see how they cope with the over night temperatures. You could also try covering them with fleece or newspaper over night if low temperatures are forecast.
Good luck with your new greenhouse, and Happy Gardening!