Deutzia dilemma

Now my Deutzia has finished flowering I need advice on the pruning. I have cut back branches that flowered but there are four 2ft long stems that had no flowers on that tower above the rest of the bush. Should I cut these back as well, or are they going to have flowers on next year? They have larger leaves than the rest of the shrub and look like suckers, but I know they are not because they are growing from the same stems that had the flowers. I can't find anything in books, so I hope someone out there knows what to do. Fingers crossed.

If they are too tall, then cut them back by about half. That way you will get more new branches from below the cut and thus more flowers next season.

Doris, Deutzia is very slow growing and needs little or no pruning, my own is now 25 years old, has moved at least twice to find the position it loves and this year flowered for a long time and very profusely, the early bees and hover flies loved it. The plant is only four feet six tall after all this time.
I did find some very long stems and on tracing them back to the root found they were bird dropped seed that had struck, what ever it was came out leaving it looking a bit raggy so the hedge trimmer gently ("err" well as gentle as you can be with a hedge trimmer) went over the top rounding it off nicely, I did not take off more than an inch or so.
Sometimes what looks cruel is a kindness and at my age the hedge trimmer gets a lot of use.

Frank.

Thank you both. The bush itself is a nice round shape but had these 4 'horns' towering above that look so out of place. A bit like a  table upside-down! I'll give them a trim as suggested. Thanks.

Bit worried about the slow growth of Frank'sDeutzia. All of ours grow 3 to 4 feet a year after flowering is over and need a trim to keep them within bounds.

I agree with Berghill, Frank, what variety do you have as Deutzias normally  grow 2ft to 3ft per year, and should be cut to shape immediately after flowering.

There are from 40-60 species of Deutzia from Rosa height and spread around three feet to Scabra height and spread six to eight feet, Bibrida can go over eight feet as well as Magnifica.
They are usually problem free and need very little pruning in June July after flowering, With taller plants it is best to selectively remove old stems from the base to promote new growth.
My own Deutzia Rosa Gracilis a pure white flower is a slow grower and with a sweep over with the trimmer every couple of years keeps its shape and height. Its roots are cool in good loam and with a mulch retains moisture, its flower heads are high enough to get almost all day sun (when we get any sun) and as I said has had two moves to this position where it thrives.
Any questions?

Frank.