After reading that you had lost seeds in the hotbed to mice I thought I’d share my experience …last year I lost sowing after sowing of beans & peas both in the hot bed & outside even whist trapping them.we are very near woods & have a hedge close by so there are many mice voles & shrews. This year I was determined to get at least some past them someone told me about using pepper I’m not sure if they are confused by the smell or they just don’t like it ..I bought the cheapest fine ground pepper from the supermarket & covered all sowings enthusiastically (a bit tricky in the wind !)every 2 or three days to keep it fresh. Low & behold they never touched them!! I now have lovely rows of flowering board beans & the pepper pot is never far away .I hope this is helpful to you all