Posted: 23/03/2015 at 13:35
I have just got a cold frame and it's brilliant. It has free'd up the greenhouse for more newbies and is a great way to harden off plants. I open it up most days as it can get quite warm. Mine is in full sun which may not be wise in a month or two but works well at the moment.
Last year I used one of those plastic greenhouses to harden off and it worked fine.
Lucy - make sure your lobelia seedlings are well established before putting in a cold frame as the night temperatures are still abit low, I'd wait another month at least.