Hi - I have had a deutzia in a tub for the last three years and it has never flowered! What am I doing wrong

If the plant had died back and has had to re-shoot from lower down to make up the growth it lost, then it won't flower. These shoots will next year though as the short side shoots that come of these stems next year will carry the flowers.

Being related to Hydrangea, Deutsia like cool root runs and may not be the best thing for a tub. You should perhaps consider putting this into the garden if possible especially as it only has a short flowering period. You want something in the tub that is going to pay its way!

What about a Viburnum Tinus 'Eve Price' or something that looks nice but you also get something from it like a Blueberry?

Thanks very much Fractal - I was wondering if putting in the ground was the answer. Should I cut it back this autumn or leave it as it is now?

How tall is it? I have one in the garden so the roots can spread and it flowered this year, it is only about 12 inches tall. They like sun to partial shade and look lovely as part of a herbaceous border. They seem to be the replacement for lilacs and I think that is great, lilacs are pain!!

I wouldn't cut it back, just plant it or you won't get any flowers next year.

Plant it as has been said already AND be sure to water it a lot more than just the first bit of 'watering it in'. - Half a gallon every few days right now would be a fair example of what it will need if the heat persists.....

'Deutzia prefer glades' so plant yours among shrubs of similar size - it WILL reward you next May.

And if you have D. gracilis or D. 'Magician' consider yourself doubly fortunate....... They're the best in my view.

BTW Viburnums are an excellent garden shrub as Fractal suggests - they too will be happier and more resilient in the ground.... unless of course you've got a roof garden!!!! (Who knows?)