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Has my callistemon bottled its flowering?
Q I have an established bottlebrush tree that refuses to flower. Two years ago I cut it right down to the ground. It started growing again and is about 5ft (1.8m) tall now, but still no flowers. How can I get it to flower?
Jennifer Pritchard, via email
A The ideal conditions for callistemon are full sun in moist but well-drained soil, protected from cold winds and frost. They can cope with most soil types, but won’t thrive on shallow chalky soils or soils prone to waterlogging.
The flowers are produced on the ends of stems grown the previous year, so hard pruning will have affected flowering for a year. If the stem tips get damaged by frost this could also affect the production of flower buds, so shelter and frost protection are really important.
As a final thought, you could feed in late summer with a fertiliser high in potassium to encourage flowering and flower-bud set. It
