Act now to control winter grass!

Author: Stefan Palm   Date Posted: 10 February 2021 

Did you know that there is a herbicide that you can apply now which will stop winter grass from coming up in Winter? Sounds hard to believe doesn't it!

Wintergrass is probably far from your mind now, but you might be surprised to know that now is the best time of year to knock it out. 

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 -  It's an annual weed meaning it only lives for a short time and only comes up at a certain time of the year. For wintergrass, its season is typically from April through to September.

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, more 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 during winter, when you can see the weed. 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 of the weed before it germinates which I have to say is a far better way to approach to this problem. There are products that you can apply such as Spartan and Pendi Pro that will act as a preventative treatment and literally stop the wintergrass seed from germinating meaning you won't see it come winter.  

Spartan

Spartan is a liquid pre emergent herbicide which is sprayed on. Apply every 16 weeks from February through to August. It is effective against major annual grass weeds in turf during winter and summer.  Being an unscheduled chemical, it's safe for use in public areas. 

  • A 500ml bottle covers up to1600m2
  • Safe for use on most lawns including Couch, Kikuyu and Buffalo lawns
  • Apply every 16 weeks

Pendi Pro:

Pendi pro is a pre emergent herbicide combined with a granular fertiliser. It comes in a 20kg bag and can be applied with a spreader: Apply every 6 weeks from February through to August. 

  • 20kg covers 600m2
  • Safe for use on Couch, kikuyu and zoyzia lawns. Do not use on buffalo
  • Apply every 6 weeks

The one you choose will depend on the type of lawn you have (eg, you can't use Pendi Pro on buffalo). It will also depend on whether you prefer spraying a liquid over your lawn or spreading out a coated fertiliser. My preference is the Spartan as it lasts longer in the soil and covers a larger area.

The best time of year to do this is a few months before the weeds start to germinate – i.e. February to March.  The chemical stays in the soil for between 6  and 16 weeks (depending on which product you use and literally stops the wintergrass seed in the soil from germinating.  If you've been battling with it for a few seasons, try Spartan or Pendi Pro. While they are expensive to buy, they are an absoulte weapon against winter grass. 


Comments (44)

Winter grass

By: on 20 August 2021
Hi can you tell me is there any product l can use on tall fescue lawn to kill winter grass. Regards sue

Paul Munns Instant Lawn Response
Hi Sue Thanks for your enquiry Unfortunately there isn't anything selective to control Winter Grass in Tall Fescue lawns

Tall fescue and winter grass

By: on 12 August 2021
Hello, I see in the above comments there is no way to Control winter grass in tall fescue. Will winter grass die off after winter or should I be removing it as it appears? Or open to other suggestions.

Paul Munns Instant Lawn Response
Hello Mat Unfortunately there isn't anything selective to control Winter grass in Tall Fescue. I would recommend to get it all out (as much as possible) Winter grass will die off in the heat of Spring and Summer but will drop the seeds in the soil and germinate next winter Thank you

poa weed

By: on 5 July 2021
Paul - I have a santa ana lawn . Is it safe to use spartan in this lawn and when is it best used . Is it too late now

Paul Munns Instant Lawn Response
Hi Alan Thanks for your query Spartan is safe to use on Santa Ana. Best to apply it in Feb/March next year. Bit too late now Thank you

Is it pet safe

By: on 14 June 2021
Is this product pet safe and how long after application can pets return to the area

Paul Munns Instant Lawn Response
Hi James Thanks for your query Yes, it is ok to use if you have pets. I would just recommend to allow drying time of the product before pets go back on the area Thank you

Winter Grass

By: on 10 April 2021
Hi I purchased Embargo from you last year and had great success with it. Have used again this year. For how many years should I use it do you think to ensure no more winter grass? Regards, Dianne

Paul Munns Instant Lawn Response
Hi Dianne Thanks for your enquiry I would recommend applying it every year. You never know if a bird or wind etc may cause it to come back in your lawn

Embargo March 21 /2021

By: on 21 March 2021
Hi Paul, is it too late to use Embargo to kill Winter grass in Sir Walter lawn. Regards, Margaret.

Paul Munns Instant Lawn Response
Hi Margaret Thanks for your enquiry It's not too late as long as the Winter Grass hasn't germinated Unfortunately we no longer sell the Embargo. We have a new product called Spartan which you can use as a pre-emergent

Tall fescue

By: on 20 March 2021
Hi there is there a product that can be used to control winter grass in tall fescue lawns please.

Paul Munns Instant Lawn Response
Hi Tim Thanks for your enquiry Unfortunately there isn't anything selective to control Winter Grass in Tall Fescue lawns

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