Nut Grass – Identification and Control

Nut Grass – Identification and Control

Nut GrassNut Grass is an annoying fast-spreading long-lived perennial lawn weed that grows from underground tubers.

A member of the sedge family – other names are nut sedge, coco grass and Java grass – it thrives in hot weather and areas with poor drainage.

Nut Grass can lay dormant underground for long periods, reappearing after disturbance by cultivation or when annual weeds have been removed or crops harvested and there is no competition for water or nutrients.

Nut Grass is often introduced to gardens in contaminated soil brought in for garden beds or for top dressing lawns.

Because of its creeping network of underground stems, called rhizomes, nut grass can sneak into your lawn from nearby footpaths, gardens and parks.

Nut Grass can be very difficult to control, so it’s best tackled early.

How to Identify Nut Grass

Nut Grass has a very narrow leaf and is easily distinguishable from most turf varieties.

It can grow up to 50cm tall, putting out three blades from the base of each three-sided stem. The roots can run very deep, reaching as far as 20-30cm under the surface.

New plants usually grow from the nut-like tubers that develop on the underground rhizomes. Young tubers are white on the inside, turning a reddish-brown colour at maturity.

From summer to autumn, mature Nut Grass plants put out elongated spikelets bearing small flowers that can range from reddish-brown to purplish-brown and tiny seeds.

If you see native birds digging into your lawn with their beaks, it would pay to do some digging of your own because they may be feeding on Nut Grass rhizomes.

How to Remove Nut Grass

There are two main methods of Nut Grass control: manual and chemical.

Manual control of Nut Grass

Depending on the size of the infestation, removing individual plants by hand can be time consuming but effective.

Don’t pull out Nut Grass plants so they break off at ground level because new plants will shoot up from the underground rhizomes.

The best way to tackle Nut Grass is to target small plants before they’ve had a chance to develop an extensive rhizome network under the ground.

Soften soil with water and gently loosen it with a garden fork before you carefully follow the roots, taking care to collect any rhizomes or tubers of the Nut Grass along the way.

If that takes too long, or there are too many Nut Grass plants, use a sharp spade to dig it up when it’s small.

Leave a generous margin around the Nut Grass plant and make sure you go deep enough to capture any rhizomes or tubers.

Whatever you do, don’t put Nut Grass plants into the compost heap, because they will go wild.

Chemical control of Nut Grass

There are several herbicide sprays on the market that are suitable for managing Nut Grass.

Depending on the maturity of the Nut Grass plants and how large an area is affected, it may be necessary for you to spray more than once.

Glyphosate can be effective on Nut Grass, but as a non-selective herbicide it will poison everything it touches, including the lawn.

It is best applied to actively growing Nut Grass plants in late summer, from February to mid-April, when at least 20-25% have reached the head stage and repeated 6-8 weeks later.

Selective herbicides, containing the active ingredient halosulfuron-methyl, are less dangerous to your lawn. This chemical also can be absorbed by the Nut Grass plant and translocated into growing points, including rhizomes and tubers.

The Nut Grass plants must be actively growing and not under any stress for them to work. If successful, Nut Grass will stop growing, yellow in 2-3 days and die after 14-21 days.

Recommended Products

Indigo Halo Force Herbicide 25gm

Indigo Halo-Force 750WG 25gm is a dry flowable granule herbicide that disperses in water and can be used for selective post-emergence control of Nut Grass. Grasses that Indigo Halo-Force 750WG can be applied to are KikuyuCouch and Buffalo. Always read the safety directions and instructions on the product label before use.

SHOP NOW

Tuffweed Liquid Glyphosate 1L

TUFFWEED Liquid Glyphosate 1L super concentrate is a non-selective herbicide that combats the toughest of weeds such as Nut Grass. Before use always check to see if your lawn variety is suitable for the use of TUFFWEED Liquid Glyphosate 1L. Always read the safety directions and instructions on the product label before use.

SHOP NOW

How to Prevent Nut Grass in Your Lawn

Monitoring

Check garden beds, footpaths, driveways, roadsides and other nearby areas to ensure there is no Nut Grass that can sneak into your lawn.

Mowing

Don’t scalp your lawn by mowing it too short – this can stimulate Nut Grass growth.

Encourage the lawn to grow taller and thicker, so it can crowd out Nut Grass and other weeds, and always mow at the correct height.

Drainage

Nut Grass thrives in full sunlight and poorly drained soils.

Eliminate wet spots in your lawn and lay geofabric under new garden beds to minimise the risk of Nut Grass spreading from seeds or tubers in soil that’s brought in.

Free Lawn Guide

Sign up for our Newsletter to receive your free guide.

View our Privacy policy
Seasonal

Related Articles

How to remove White Clover from your lawn

White Clover is easily recognisable from its smooth trifoliate leaves but once established can require patience to beat. A hardy, herbaceous perennial plant that tolerates ...

Read More
Chickweed

Controlling Chickweed in your lawn

There are several types of Chickweed, a common herbaceous plant, that prefers cool, damp shady sites and can quickly take hold in your lawn during winter. Mouse-ear Chickweed ...

Read More

Removing Sedge Grass from your lawn

There are hundreds of sedges in the genus Cyperus, which is found in both tropical and warm temperate environments across the world. Some Sedge Grass is grown as ornamentals ...

Read More
Dandelion Weed

Dandelion Weed removal from your lawn

Dandelions are a perennial herb that gardeners either love or hate. Some people loathe Dandelion Weed with a passion because it can reappear in lawns year after year, despite ...

Read More
Crowsfoot Grass

Controlling of Crows Foot Grass from your lawn

Crows Foot Grass is a common weed of lawns, gardens, parks, footpaths and roadsides. It was recently ranked in the top 200 environmental weeds in south-eastern Queensland and ...

Read More

Ridding Mullumbimby Couch from your lawn

Mullumbimby Couch is one of the hundreds of sedges in the genus Cyperus, which is found in both tropical and warm temperate environments across the World. Some Sedge Grass is ...

Read More
Summer Grass

Ridding Summer Grass from your lawn?

Summer grass is a common invasive annual grass that also goes by the name crabgrass. Not surprisingly, Summer Grass seeds germinate when temperatures begin to rise above 20 ...

Read More

How to remove Soursob from your lawn?

Also known as Sour Grass, Bermuda Buttercup and Creeping Oxalis, Soursob is an extremely annoying fast-spreading weed. Soursob is sometimes confused with Clover – they have ...

Read More

Identifying and Removing Onion Weed from your Lawn

The bulb of an Onion Weed plant gives off an onion-like scent when crushed or cut and an outbreak can be enough to make any lawn-lover cry. A perennial, Onion Weed has been ...

Read More

A Guide to the Most Common Lawn Weeds

Weeds may be green, but they are plants growing where they’re not wanted within your lawn. Weeds can take any form and can vary depending on where they grow and typically ...

Read More