mine puts on about 4-5ft every year. I chop it down to knee height and by mid summer its 5-6 ft tall again.

Crumbs....how long is a piece of string?......it depends how hard it is cut back....the harder the cut....the more it grows.......

yes I agree, I cut one hard back last spring at the end of the summer it was as big as ever

Hi Guest iv read that if u want a Few Large Flowers 2 Chop/Prune it really well & if u prefer Smaller & More Flowers then Prune a little ! Hope this helps2? :)

Growth rate is anything up to 6 foot in a year. BUT unless you prune back each year you will have a tall straggly shrub that only produces leaves and flowers on the top quarter. Cut back hard every year and it will produce lots of new grow with lots of flowers which the butterflies will give much thanks for.

Jacque my experience is prune hard, you will then get lots of new flowering spikes...

Thanx MG :)

Moon grower: I have been out pruning my bushes, and this is one plant that can use a "grumpy" mood. I thought it would make a nice screen, and when I just stuck some cuttings in the ground, they came up and I have been fighting them ever since.

Go ahead and great 'grumpy' Wylie!