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They are inside (not without some moaning from some quarters) so ought not need further cover, I assume. Just hope they recover, there are 64 of them and they cost a bit. All advice I can find from websearches say out when no risk of frost, which I thought was finally the case; no mention of a month. Also says later to harden them off by putting out in the day and in at night. Can't see that happening, even if we get that far.
Bit of a mistake getting them I suppose, but I don't recall this being made known in the catalogue. Perhaps worse, I've plugs of different plant species (Petunia Tumbelin & Coleus Canina) out at my place, and I won't be getting back for days. Just hoping they're more hardy.