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Clumps of Solomon's seal are prime targets for sawfly caterpillars. Squeamish gardeners can treat them with malathion or derris. More vindictive ones can pick them off and stamp on them.

Roses should be deadheaded regularly. Take off the flower and the leaf below it, cutting the stem just above the following leaf. Tidy up bushes of weigela and philadelphus as soon as they have finished flowering, cutting back at least a third of the old flowered stems to make way for new growth. Cut back the old flowered stems of sweet rocket close to the base of the plant, unless you want to encourage it to self-seed.

Pick over clumps of pinks regularly, nipping off dead heads to encourage new flowers. If you want to increase your stock of carnations and pinks, layer them by pegging down shoots on the outside of the clumps. They should root within six to eight weeks.

Cut back herbs such as sorrel and tarragon which are beginning to look scraggy. Tarragon will sprout again quickly. Last year's parsley has suddenly shot up to seed. This is your cue to sow a new row of seed. If the ground is very dry, moisten it well before sowing. Keep basil plants watered and fed so that they produce plenty of fresh leafy growth.