- The big, rampant Clematis montana can be pruned as soon as it has finished flowering. Where space is tight you can reduce it to a framework of pencil and finger-thick stems; where it can be let go, just take back the longest, most questing stems.

- Don’t let peonies flop under the weight of rain; make sure they are supported.

- Watch out for aphids colonising the young shoots of roses.

- This is the month for seedling weeds; keep the hoe and handfork busy now. Get out buttercups and goose grass while they are easy.

- Time to trim the flowered shoots of early-flowering shrubs: perfumed Osmanthus delavayi and heathers Erica carnea and darleyensis. Take off the flowered section of stem, down to promising sideshoots.

Readers’ queries

I have a flowering cherry tree covered every spring with blossom, but there is a root showing above the grass. The bit I can see is about 6ft long, and as thick as my forearm. What should I do? My mower passes over it quite easily.

Mr J. Graham, Radcliffe on Trent, Notts

Cherries are devils for producing these shallow main roots. If you uproot a mature cherry you will find a great club of wood at the foot of the trunk and then a ring of these fat surface roots. It is this intense surface-root competition which makes it so difficult to garden under cherries. This, come to think of it, is probably partly why the Japanese go in for cherries standing with absolutely nothing beneath them; it also makes the ground conveniently clean for a carpet of petals.

Leave your root well alone. If the mower passes over it that’s good, because damage to the root is not only ugly but also lets in disease and encourages suckers. If the tree has a sufficiently dense surface root system to have made the grass beneath weak and mossy, then I would be tempted to kill the grass in the autumn with glyphosate (which won’t harm the tree or the moss), then let the moss take over. The odd bit of hand weeding should suffice thereafter, and there’ll never be root damage from mowing.

I planted a flowering quince ‘Moerloosei’ four years ago. Over the past year it has thrown up lots of whippy branches from the base, on which there is no blossom this year. I wonder whether they could be suckers. Do you think they are grafted on to a rooting stock?

Mrs R. Carmichael, North Berwick, East Lothian

There’s no reason why a chaenomeles (‘Japonica’) should be grafted – they are easy enough from cuttings. ‘Moerloosei’ is a lovely variety and most appropriately sometimes called ‘Apple Blossom’; it is a much more accommodating colour than the hard reds and oranges of most japonicas. You might say the white varieties are accommodating too, but small white flowers on an almost leafless shrub don’t make much contribution. The whites look best on a coloured wall and the blood-reds on a pale wall.

It’s not unusual for a shrub that has languished in a pot to shoot from the base when it gets its feet under the table. But those whippy shoots will not flower until they have settled down. Be patient till next year.

stephen.anderton@thetimes.co.uk

Explore Property

• Buying & Selling

• New Homes

• Overseas

• Interiors

• Investment

• Gardens

• Specials

Times recommends

• Here comes the glass sun – garden honours Beatle
• Gardening tips: 10 things to know about Horny Goat Weed or Epimedium
• Diarmuid Gavin shares tips on how make your garden fun and funky