By Jennirot
Hampshire,
United Kingdom 
I have a very tall mallow but don't know if it is annual, perennial, shrub or tree. It is as tall as me (over 5 ft) and has lots of long arching stems, the flowers are pale pink and bloom all along the stems.
Should I cut it back with other border plants as I don't want ti straggley next year.
How much do I prune off - cut it right down as I do with a lot of my perennials - or what?
Help
7 Oct, 2012
Answers
From your description it sounds as though it could be Lavatera Barnsley, in which case it is a short lived shrub, and you can cut it back quite drastically in the spring.
7 Oct, 2012
did you plant it this year or have you had it in the same spot previously? are the stems woody? if yes then it is a shrub.
I think I would wait until next spring. any chance of a photo to help with the id?
7 Oct, 2012