[dom_a]

I've picked up some marrowfat peas for planting on my allotment and was wondering if they can be planted in autumn for overwintering like othe pea varieties.  Does anyone know if this is possible?

[mumofstig]

I've never found any pea varieties to be winter hardy, outside.. One hard frost and they're done for. I've never tried them under glass for the whole winter, though.
My earliest mangetout, a very old hardy variety, Winterkefe, get planted towards the end of Jan in the greenhouse.

[Subversive_plot]

I only grow the mangetout types (snow peas and snap peas).

I do plant in mid to late fall, while we still have some warm days, to get plants that will overwinter and produce early in March, if the weather is good.

Spring 2022, that strategy didn't work so well.  It stayed too cold for too late, then rapidly got too warm.