I don't think it will die off in May in the UK, I suspect it dies back in May in it's home range due to the temperature getting too high and it getting too dry, here it certainly grows all summer long (we grow it to sell over summer) and my summers are comparable to the midlands. that is also alluded to in that wiki article. I also do not think that a thin layer of plant leaves is going to offer any frost protection, unless you are down in Cornwall or somewhere where it really is mild.
posted 1 year ago
I'm pretty sure ours was dead by June last year, it's seeding and yellowing at the moment. Running a mower over it around now would almost certainly finish it off I think.
I guess I was imagining the air pocket between the leaf canopy and the ground would act as the insulation.
I'm just North of Bristol so reasonably mild. I guess I'll try it on a small area to start.
I've had claytonia on my allotment in Staffordshire. For a year or maybe two it did seed itself, but it wasn't much of a trier. I think the slugs liked it too much, and the seeds are very fine. Corn salad, now, is a different matter, I sow it in autumn just chucking the seed all over the place and it stands all winter, and it seeds itself too. About now it is coming up to flower so I can imagine something perennial would come through it quite nicely. It just looks more blankety to me than claytonia, the foliage is denser and more complex than all those spindly little stems with leaves on the end.
That said, for sheer insulating power I'd be more inclined to trust in a layer of dead leaves or straw.
We have a winter annual ground cover here called deadnettle; That is it looks like miniture nettles but has no stingers.
https://en.m.wikipedia.org/wiki/Lamiaceaelink Self sows in disturbed soil this time of year and only grows during the winter.
Chick weed can form a denser mat but tends to grow mor in the spring so not as good at frost protection.
I have had runner beans come up from the overwintered roots when mulched with maple leaves.