Move hardy seedlings gradually outdoors from their cosy quarters in the greenhouse or cold frame from this week, ready for transplanting into their final growing positions in the open garden.
Don't do the job in too much of a hurry, though. March can be a chilly month, and it's worth remembering that if you don't relish stepping from your nice warm house out into the freezing cold, your seedlings won't be too keen either. In fact, taking seedlings out of the cosy environment of a greenhouse or windowsill and planting them out straight away sends them into shock, and they may never recover properly.
Instead, take your time and get them used to the colder conditions. Start by moving them into the cooler conditions of a cold frame for a few days, then start opening the cold frame lid by a crack during the day. Over the next two weeks, gradually increase how wide you open the lids until they're fully open in the day and only closed at night. Finally leave the lids completely off and wait till there's a warm spell before you finally plant them out. Gradually acclimatised like this, they'll hardly even notice they've been moved.