Act now to control winter grass!

Author: Stefan Palm   Date Posted: 19 February 2018 

Winter grass (otherwise known as Poa annua or annual blue grass) is that annoying light green coloured grass that comes up in your lawn every winter Winter grass (otherwise known as Poa annua or annual blue grass) is that annoying light green coloured grass that comes up in your lawn every winter

If you have it, you’ll know exactly what I’m talking about. It produces lots of seeds and has a white cotton like root zone. It’s easy to pull out but there is always so much of it and more often than not, as soon as you pull it out, it seems to grow back. The most annoying thing about this weed by far is that it gets worse every year! This is because wintergrass produces large amounts of seed, which fall to the ground ready to germinate next year. If each wintergrass plant produced 50 seeds, you can see how quickly this plant can get out of control.

Now that we know what we’re dealing with, the big question is how do you get rid of it and how do you successfully keep it out. There are 2 methods for controlling winter grass. The first is post-emergent control and the second is pre-emergent control.

Post emergent control is where you selectively poison out the weed after it germinates (ie during the autumn and winter months). There are products such as Kerb and David Grays Wintergrass Killer that are designed to selectively control wintergrass in couch. These products only work if they are applied exactly as directed and can take a considerable amount of time to work. Control can take anywhere from 2 weeks to 2 months which can frustrating because there are often successive waves of wintergrass that will germinate giving the impression that your control measures are not working. If applied too late into the winter, it can be hard to get a result at all. 

Pre-emergent control works on the principle that you control the seed before it germinates. There are products that you can apply such as Embargo ( for buffalo lawns) and Pendi Pro (for couch and Kikuyu ) that stop the seed from germinating.  The best time of year to do this is when there are no wintergrass weeds present – eg January to March and if done properly will result in very little to no wintergrass seed popping up in your lawn come winter. Pre emergent control is by far the best way to control wintergrass. If you've been battling with it for a few seasons, try Pendi Pro. Its an absoulte weapon against winter grass. 

Comments (6)

Santa Anna Lawn

By: on 8 September 2018
When do you apply Pendi Pro and how much?

Paul Munns Instant Lawn Response
Hey Leoni, If your attacking winter grass seed in couch, Pendi Pro should be applied between March and April. It costs $99 for a 20kg bag which covers 600 square metres. Unfortunately this is the only size it comes in. We do have an alternative called Embargo which is also a pre emergent herbicide like Pendi Pro. It comes in a 500ml bottle, covers around 1000m and costs $65.

What to use on Kikuyu for winter grass?

By: on 22 August 2018
Hi Ive missed the boat and winter grass has emerged. Is there anything for post emergent treatment of kikuyu? Or do i just pull it now no do pre emergent early next autumn? Many thanks Will

Paul Munns Instant Lawn Response
Hey Will, I'm not aware of any post emergent herbicides that can be used on Kikuyu to selectively control winter grass. The best way for you to stop winter grass coming back next season is to use a product called Emabargo. Its a pre-emergent chemical that will kill the seeds of the winter grass and therefore stop it coming back next season. The best time to apply this chemical is in March.

Winter grass in fescue

By: on 27 July 2018
Hi Paul, did you manage to find out if you can use pendi pro on fescue?

Paul Munns Instant Lawn Response
Hey Todd, I've had a read up on the Pendi Pro label and it doesn't specifically list Tall Fescue as a variety you can apply it to. It doesn't specifically exclude it either (there is a warning not to use it on Bent, Carpet Grass, Buffalo and Dichondra). Because it isn't on the label, I can't advise you to use it on Tall Fescue. Sorry Mate!

Low cost, small qty, pre-em for winter grass in ki

By: on 15 May 2018
Is there a pre-emergent product marketed for control of winter grass in residential (up to 200m2) kikuyu lawns at an affordable price? Say under $30

Paul Munns Instant Lawn Response
Hi Dave Not that I'm aware of. It seems that companies producing these types of chemicals are registering them for commercial use (hence the large pack sizes and coverage). Products containing Propyzamide such as David Grays Wintergrass Killer (which is available in a 200g pack) will have some pre-emergent effect but not as much as a specialised active such as pendimethalin (Pendi-Pro). While Pendi Pro will cost you around $100, when applied in feb/march it will do an excellent job of stopping wintergrass seed germination.


By: on 10 April 2018
What product is safe to use for the control of Winter grass in Fescue lawn?

Paul Munns Instant Lawn Response
Hi Tamieke, As far as I'm aware, there are no products that specifically state they will control wintergrass in tall fescue. There is however a product called Pendi Pro that doesn't say it can't be used on tall fescue but it doesn't say it can either. I'll do some research with them and see if it's possible.

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