Philadelphus — mock orange — needs pruning now. Cut out any stems that cross through the middle of the bush and take out half the flowered stems. Take out the odd stem at the base, too. Prune tall varieties lightly or they will run to leaf. Brown colchicum leaves can be pulled off. Lift and divide them, too, while the corms are dormant. Replant them singly as they soon bulk up again.

Snip out at the base the flowered stems of pinks. Pinch out the tips of the fat new shoots, or take them for cuttings. Push 8cm shoots into a 50:50 mix of sand and compost and they will root in no time on a shady windowsill.

Cut out the finished mauve-grey flower stems of lamb’s ears, taking them right back to some strong, leafy growth.

Opium poppies come in purple, pink and blood red. Dead-head the ones you like least to encourage more of your favourites.

Geranium ‘Kashmir White’ can be sheared off at the ground; it will soon produce new foliage.

Question time

I have two Cambridge Gage plum trees that produce masses of blossom replaced by tiny embryonic fruits that fall off. I’ve tried dabbing the blossom with a branch from a Victoria plum but there’s no change. Mr D. Graham, East Boldon, Tyne and Wear

While the Victoria plum produces a heavy crop every year on its own, most varieties need a partner tree, compatible genetically and in the time of flowering, to set fruit. Put a compatible later-flowering variety — Oullins Gage perhaps — close by.

I’ve had a pussy willow in a pot for a couple of years. I’ve noticed small black bumps on its branches that ooze a sticky goo. It has spread to a nearby bay tree. Mrs J. Picken, Gateshead

This sounds like willow bark aphids — chunky creatures, up to 5mm long, that build colonies on twigs. Like all sap-suckers it produces a goo. A general insecticide will fix them. Your bay tree probably has a different problem: scale insects, maybe, especially if it has been indoors for the winter.

stephen.anderton@thetimes.co.uk

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