Potting Shed

Welcome to my potting shed! This is the column where I’ll share all my gardening hints and tips – and I’ll try to answer any queries you may have.

What’s causing the brown spots and tiny holes that appear on the leaves of my cherry trees every spring? – Robert Chapman, Fraserburgh.

These are caused by a fungal disease called cherry leaf spot. There’s no specific treatment for this, although a spray for fungal conditions may help, otherwise the best way to deal with it is to collect and destroy all fallen foliage to prevent it from over-wintering.

Can you identify a tall plant with grey leaves and pale yellow flowers that’s growing in my garden? – Isabel Shaw, by email.

The photograph you sent me is Sisyrinchium striatum, or Mexican Pale Grass. It likes a sunny spot with well-drained soil but doesn’t like cold, wet winters.

Can you tell me why there are no fruits on one branch of my apple tree? It is about five years old. – Ann Allman, by email.

At five, your tree is still a youngster and the chances are that the wood on that branch isn’t sufficiently mature to bare fruit. Give it a few years and it should start becoming productive.

Why is our two-year-old wisteria a mass of foliage but no flowers? – Bob & Carole Field, Leeds.

Wisteria can take up to seven years to start flowering. In the meantime, cut back new shoots now and, in February, reduce these again to two or three buds from the trunk.

When’s the best time to prune a cotoneaster that’s out of hand? - Len Anderson, Carluke.

The best time is February, but you could take out some of the longer shoots now if they are causing a problem.