I have a climbing hydrangea which I planted a year ago.d It is growing well but I snapped the top of it by accident.
Will it still grow upwards or just bush out?
Without a photo its hard to answer. It depends on how much of the top was lost, and also how it grows out and if you know how to do directional pruning.
With the apical leader snapped off, it may tend to grow laterally. But it may also put out multiple sprouts at the top where it was broken.
Water and fertilize and when you see new growth at the top, select the strongest and straightest leader or two and remove the rest. Pinch the ends of the lateral growth to discourage excess spread.
If that is a UK postal code, depencing on your local climate, your spring is almost in full swing, or soon will be. Its a good time to expect new growth, so be patient and see how it grows out. When that happens, send photos and we may be able to give you more specific advise.