Perennial sweet peas

If you mean lathyrus latifolius, that is hardy and will grow next year, without any protection. Some of the other perennial ones can be a bit more tender, so it depends which variety you've got. Just pull off the dead topgrowth when its dead, or you can cut it at the end of this month if you want.

I've grown some too this year! My mum says you cut them right back to the ground in the autumn, & they will grow like fury next year. She used to have a huge one in her garden, so I guess her advice is right. I remember from my commuting days in London that there were lovely everlasting peas on the rough land at West Croydon station, & I don't imagine they got much fussing over.

Ok, Thanks very much for the advice.On the seed packet it says Sweet Pea Everlasting Mixed. They are still very green, dont look as if they are dying off at all..I didnt get many flowers maybe cos its their first year of planting.

They're hardy, Strude - I never used to cut mine down, just used to pull off the dead topgrowth once it had died right back, and that can often be quite late in the year.