Summergrass leaves have a green-yellowish colour with light purple or white sheaths at the stem base. Seed heads appear throughout spring, summer and autumn and consist of multiple small, finger-like spikes radiating from a central point and covered in tiny black seeds.
During Spring when temperatures raise above 20 degrees Summer Grass begins to germinate, and it can be quite invasive, especially when we are having a mix of wet and warmer days.
Summer Grass flourishes in open areas of full sun or partial shade and is commonly found in vegetable gardens before it appears in your lawn.
Seeds, plant segments and roots are commonly transferred by garden tools and animals, and are also common in cow manure, so be especially watchful for Summer Grass if you’ve just applied manure to your garden this Spring.
Removal of Summer Grass
There are several ways to control Summer Grass, either by hand or with herbicides.
We find that the best method is to carefully hand remove individual plants when they appear. Some people mow patches of Summer Grass if it’s a large patch, before it puts out seed heads, sure, this will help reduce the spread from seeds, but won’t stop it from spreading via runners.
If you do have a large patch of Summer Grass and you don’t want to use chemicals to kill it, a option is to place a plastic bag or sheet over the weed for a few weeks and essentially cook the weed and its seeds. The downside is that you’ll also likely damage your grass in the process.
Herbicide control of Summer Grass
There are several safe herbicide sprays on the market that are suitable for managing Summer Grass.
Depending on the maturity of plants and how large an area is affected, it may be necessary for you to spray more than once.
Glyphosate can be effective on Summer Grass, but as a non-selective herbicide it will poison everything it touches, including the lawn. Overspray of glyphosate is especially toxic to Buffalo lawns.
It is safer to use a selective herbicide. Look for products containing MCPA (that are also marked on the label as being suitable for Paspalum, Nut Grass and Clover) or the active ingredient oxadiazon.
The Summer Grass plants must be actively growing and not under stress for any herbicide to work properly.
DSMA Clear by NuTurf provides effective control of Summer Grass. It can be a bit tricky to find a local supplier but you can find a list of wholesalers on their website.
Over many years DSMA has proven an effective, reliable selective weed killer. Arguably the most widely used herbicide on sports fields, it controls difficult and unsightly grass weeds in recreational and sporting turf
Another option in controlling Summer Grass is to use a pre-emergent herbicide, and a common herbicide is Freehand by Amgrow. This is a perfect tool for pre-emergent weed control of annual grasses such as Summer Grass, for the home gardener it is best to apply any pre-emergent herbicide at the end of Summer and at the end of Winter, this will give your lawn the best chances of controlling weeds before they appear.