Nothing - just keep it watered as necessary. It should flower around May time, maybe a bit later depending on the weather. Once the flowers fade, trim them off directly behind their bases - don't leave them in place because the plant will produce new growth at the top end of the flower, and you'll end up with a stem that eventually looks bald where the flower has been.

It would be useful to know which variety of Callistemon it is in terms of knowing its growth habit and the shape its likely to make as it grows.

Thanks for your information - you have helped me previously, I remember! I do not have any more information concerning variety etc. I know it is
evergreen and hardy, that is all. It doesn`t look as if it is going to flower in May though,.

Betty at Beckonscot.

You could post a photo if you're still a bit concerned - if its not very old, it may not flower this year, but they don't form till much later - I've got one on my balcony and I checked today - not a sign of any flower, but it does flower every year. They don't form obvious buds like other plants - a funny sort row of bumps arrive near the end of the stems later on, and they're the flowers.