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.

I’ve had beautiful asters in the garden for about five years, but this year there were fewer flowers. What is wrong with them? – Paul Bird, by email

Asters lose vigour over time, but you can rejuvenate them by dividing them, discarding the old parts of the clump and replanting the newer sections.

I’ve tried growing Sedum spectabile several times, but it never lasts very long in my garden. Why is that? – Selina Morrison, Lesmahagow

Do you have heavy soil? Sedum, or Hylotelephium as it is now called, likes really free-draining conditions.