Wisteria just not growing....why not?

I have 2 separate Wisteria both in big pots. In J.Innes no3 and fed with rose food as recommended. Both 2 OR 3 yrs old (they were a present before I started gardening) Ive had a few beautifully scented flowers on both of them each spring and the foliage is very healthy. Interestingly the foliage comes first and I thought it was the other way round. However …………..they are just NOT GROWING! I was so afraid I wouldn't know how to prune them as was told how vigorously they grew but I really shouldn't have been concerned as they are pretty much still the same size. Any ideas why this is and what I can do about it please? Its so frustrating

 

Yes I think I know why Cindy.

Wisteria are hungry....nay greedy ...plants.
They need room to grow....plenty of room....so growing in containers is not ideal. The one growing here has huge allotted space in the garden and it grows and grows hence the need for pruning.
John innes is good but I would do 2 things......add fish blood and bone and mulch with a blend of mpc and dried manure or chicken pellets. Not sure about the rose fertiliser but a supplementary weekly high potash feed may help.
As for flowering, you are doing well.....they can take a few years to flower.

Be patient ....with good feeding I think your wisteria will suddenly take off....then you can worry about the pruning. In any case, pruning is not too difficult

Flowers before leaves? It simply depends on the variety you have ......Chinese or Japanese.