A little tip a few may find useful which I've used for a few years . Many seed packets say "plant out when the risk of frost has passed". The trick is to plant out as early as you can, but not if frost is likely to kill the plant, so here is a way to help. Save any 2 litre clear plastic bottles (lemonade, coke, cider etc) and cut the bottom off. You then push it into the ground around the young plant and it helps in 3 ways. It stops pests like slugs eating the plant, it keeps the plant warmer by acting as a mini-greenhouse, and it conserves moisture. This video explains it:
https://www.youtube.com/watch?v=hwxESy5cL_k