Having just stuck in a few last year and to late in the season at that,I've very little to offer.
What I will say though is pick where you plant them very carefully.
I put 3 cascades and a fuggles in, 3 of them along a fence thats in sunlight most of the day, the other 1 in a more shady spot.
The difference was unreal, the 1st 3 made around 10' I'd guess, the runt didnt even make one foot.