I think the site that lists these seedbed rolls slightly over-eggs the difficulty of growing salad, particularly if you grow it in windowboxes, but I’m still intrigued by the idea. The seeds come with their own mat and polytunnel built in – you just lay the roll on the soil, weigh down the corners and water it, and the seeds will both root the mat to the floor and push the polytunnel up over themselves as they grow, so they have their own environment protected from slugs and snails.
OK, it’s not as eco as growing your own seeds without a polytunnel but if you’re too short on time to keep an eye out for slugs and snails, only have an outdoor space and like the idea of growing your own salads then it’s a potentially time-saving alternative to usual methods. Have you tried one? If so, I’d love to know what you think.