ASK DIARMUID

Q This is what my bottle brush looks like at the end of the season. Should I cut it back as it’s so sparse? I am worried it may not come back.

It flowers every year, but this year is definitely much more sparse than usual. I haven’t cut it back before.

Celia Harding

A Yes, it isn’t looking too happy at all and I think it would benefit from rejuvenation pruning next spring. You can completely remove all those dead twiggy bits that have no growth on them and I would cut back the branches by at least one third. If you can, repot into a larger pot with fresh compost – but if not, top dress the plant in spring by scraping off an inch or so of old soil and replacing with fresh compost. Regular feeding during the growing season should also help.

In colder parts of the country this plant should be brought indoors to a greenhouse as it’s not completely hardy.

That may account for its weakened condition now.