To enjoy the purple, pink and white flowers - and, in early spring, the glossy, strap-like leaves – of autumn crocus ( Colchicum autumnale), plant the corms as soon as possible. The flowers reach 4in-6in tall, so plant drifts at the front of a sheltered and sunny border, in the dappled shade beneath deciduous shrubs or in rough grass – the soil must be reasonably fertile, welldrained but moisture-retentive. Bury the corms 3in-4in deep and 6in apart.

Lavender will benefit from a light trim between now and the end of the month to keep it tidy. Use hand-held shears and clip the plants to just above the base of the old flower stems – do not cut into the old wood, as it may not resprout.

Many rose bushes succumb to powdery mildew at this time of year – the leaves look as if they have been dusted with flour. This nasty fungal disease thrives in warm, dry conditions, so one of the best organic prevention methods is to keep the ground reasonably moist. A water-retaining mulch should be spread around the base of the roses where necessary. Prune out any young shoots that have succumbed to mildew.

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