yes it will grow to about 5ft and yes you can keep its size down by careful pruning. Is it going in the ground or in a pot. if a pot then the size of the pot will help to inhibit its size.

Although it's not this variety, I prune my physocarpus right down every year, as you would for a buddleia

Thank you for your replies. It is going in the ground. I will limit its growth if necessary with careful pruning.

That's interesting Andrew. Mine has got to be much taller than me and is casting too much shade. But probably this variety is smaller than my Diablo. (So thank you feverfew for your question - hope you don't mind me sharing!

Stera - I let mine grow for several years, and yes they get incredibly large (and a bit unruly). Much easier to manage now although you don't get that peeling bark on the older wood

Oh dear, yet another job goes on the to do list..Feverfew, thank you for the question!

That's fine Stera, I really don't want mine to grow too big, so I will be watching it carefully, so thank you for chatting about your plants.