Pendulous sedge

Pendulous sedge (Carex pendula) has attractive, green strap-like leaves. It seeds freely and can become a troublesome weed in damp gardens.

Pendulous sedge

Quick facts

Common name Pendulous sedge
Botanical name Carex pendula
Area affected Damp lawns and borders
Caused by Seeds freely
Timing Seen all year round; treat spring to autumn

What is pendulous sedge?

Carex pendula is a native, found wild in damp woods and shady places. It makes an interesting garden perennial, best grown in a cool, damp soil, in a shady or sunny position but it self-seeds readily. Pendulous sedge forms dense clumps of evergreen leaves, thereby providing winter shelter for insects. This page looks at options for gardeners when pendulous sedge is becoming a problem.

Appearance

Tufted, evergreen clumps with long, strap-shaped leaves to 90cm (3ft). Arching flower stems to 1.4m (4½ft) produced May-June with 15cm (6in) long, brown flower spikes, becoming pendulous with age.

The problem

Pendulous sedge spreads rather freely by seed, especially in damp areas.

Control

The RHS believes that avoiding pests, diseases and weeds by good practice in cultivation methods, cultivar selection, garden hygiene and encouraging or introducing natural enemies, should be the first line of control. If chemical controls are used, they should be used only in a minimal and highly targeted manner. 

Cultural control

On a small scale plants can be dug out by hand. In larger areas improving drainage by installing land drains will discourage the sedge, as will liming to reduce acidity. Cut plants regularly to prevent seeding of Carex pendula and C. binervis (C. hirta grows from a rhizome and seeds much less).

In lawns and meadows: Apply a high nitrogen fertilizer to encourage strong growth of the other grasses. Selective mowing of the sedge will help limit its spread. If in a meadow situation, goats give good control of rushes (Juncus) and sedges (Carex).

Weedkiller control

In lawns and meadows

Carex are resistant to selective lawn herbicides. Individual plants can be spot-treated with a ready-to-use spray containing glyphosate. Glyphosate is a non-selective, systemic weedkiller applied to the foliage. When the sedges are killed, raking in some grass seed will help the bare patch to regrow quickly. Where weed infestations are heavy, the whole site may need to be sprayed off and reseeded. Chemical control is unlikely to be effective unless done in conjunction with improving drainage.

In uncultivated areas

If the site is heavily infested with sedge seeds, only thorough fallowing may clear the site. This is achieved by clearing the site of vegetation, preparing a seed bed, then allowing the sedge seeds to germinate, killing them (with a contact weedkiller such as Weedol Gun! Fast Acting), then cultivating again to bring more dormant seeds near the surface. The new seeds on the surface will then germinate where they can be sprayed off. The operation should be repeated, if necessary 3 or 4 times, until the top 2 or 3 inches of soil have been virtually cleared of dormant sedge seeds.

Inclusion of a weedkiller product does not indicate a recommendation or endorsement by the RHS. It is a list of products currently available to the home gardener.
 

Download

Weedkillers for gardeners (Adobe Acrobat pdf document outlining weedkillers available to gardeners; see section 3a and 4)

Links

Chemicals: using a sprayer
Chemicals: using safely and effectively
Chemicals: using spot and broad-scale
Weeds: non-chemical control

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