How to cut & prune ornamental grasses

Ornamental grasses are among the hardest working plants in the garden; evergreen varieties provide all-year-round colour, while deciduous plants make mounds of tactile foliage before their feathery flower heads emerge in summer. After they die, turning golden brown in autumn, plants can be left to provide sculptural shapes in the garden until early spring.

To ensure you get the most out of your plants every year you need to give them some cosseting. Those left for winter interest need serious pruning, while others need only light grooming or clipping to keep them looking smart.

Deciduous grasses

Miscanthus, pennisetum, panicum and other ornamental grasses left to provide winter interest should be cut back before new growth appears - pruning later can be tricky as you might accidentally remove emerging shoots. You can be really brutal and prune plants close to ground level – they’ll soon respond with lots of fresh growth.

Hand shears are perfect for the job, but you might need loppers or even a bow saw for plants with really thick stems, such as miscanthus. If you have lots of plants, make life easier for yourself by whizzing through your collection with a pair of electric trimmers.

Clear up the debris by hand or use a wire lawn rake to ensure material doesn’t remain in the centre of the clump. Finish off by spreading a 7.5cm (3in) layer of mulch around plants – garden compost, leaf mould or well-rotted manure is ideal.

Soft-leaved evergreen grasses

Evergreen grasses do not need any drastic pruning action like their deciduous cousins, but they can still look untidy if they become choked with dead growth. To keep them in great shape, all you need to do is comb your hand through the plant, from top to bottom, removing any debris as you go.

Many grasses have sharp edges to their leaves that could cut your hands to bits, so always wear gloves before giving them a groom. Among plants that will respond to this treatment are Carex buchananii, Festuca glauca and Stipa tenuissima.

Hard-leaved evergreen grasses

Some evergreen grasses, including many of the carex family, have wide, thick, hard leaves that are difficult to remove by combing with your hand. To spruce up them up, pull out discoloured stems with a swift tug or cut out carefully at the base with a pair of secateurs. If grasses have been damaged by frost or have brown edges, trim individual leaves lightly to remove – cut just beneath the dead, brown tips.