I'm new to this forum so sorry if this is in the wrong place!
I'm also new to gardening and this year i have decided to grow some flowers from seed. I've started with some sweet peas and lupins in trays which are in my greenhouse.

The problem i seem to have is mice! When i plant seeds, i go in the next day and they have been doug up and eaten!
Is this a common problem and what can i do to prevent it?