cutting back

Hi, I live in the north of Scotland and we ALWAYS get quite heavy frosts. I put a lot of my container plants into my heated greenhouse over winter, but could someone tell me if it would be ok to cut most of them back in Autumn, before i put them in. A lot of the care labels say to do it in Spring and I'm not sure of the difference it makes. It would be easier for me to do it in Autumn as i could squeeze more pots inside then as well. Any advice would be appreciated.
Thanks

Re: cutting back

Reply from Katy Elton

Hi Doreen,

It sometimes depends on what plant you are dealing with, but as a general rule most herbaceous perennials can be cut back either in autumn or spring. The reasons in favour of waiting until spring are that this creates a habitat for wildlife during winter, creates visual winter interest, and also that it offers protection to the roots from frost and the winter elements.

Overwintering them in a greenhouse will negate the need for most of these considerations however, so if it works best for you I don't see why you shouldn't cut them back in the autumn.

This is not be the best option for all plants however - double check in a plant encyclopedia any that you are unsure about.

Hope this helps!
Regards
Katy

Re: cutting back

Reply from Jude, Kent

Hi Doreen
Cutting back tends to stimulate new growth, so it would help if you could keep them cool to inhibit growth. say about 5C. Cut back as much as you like but don't let them start growing, especially as the light levels willl be way too low. The important thing is to protect the roots - if they survive, the tops will grow next year. And keep them as dry as you can without killing them. Usually it's the combination of cold and wet that kills. It's amazing how many tender plants will survive frost if they're dry. If you need to water, do it in the morning and don't wet the foliage. Wet leaves attract moulds and nasty diseases, like botrytis. Let's hope nest winter isn't as bad as the last one. Hope this helps. Good luck!