How To Choose A Weed Control For Your Lawn
This one is mostly for our warm season turf friends (St Aug, Bermuda, Centipede, Zoysia, and Bahia), but there is some solid overlap for you folks with the KBG, perennial rye and turf-type tall fescue too!
Here is the video from last weekend that goes along with this post:
(I’m going to do this same thing at a store up north here very soon)
Spraying and Praying - Weed Killer
Spraying weeds is a necessity when you are first starting your lawn care strategy. For most folks it actually remains a necessity for a couple seasons, even three.
The ultimate goal, of course, is to get a thick stand of healthy, weed-free turfgrass and the quickest way to reach that goal is to push growth on your good grass, and kill weeds selectively as you do it. Add in frequent mowing and you have a recipe rapid improvement.
Once you do get it looking good, then you back everything down into a slow and steady cruise mode. Back down the fert, back down the weed control and other hard inputs and just let your soil take care of the rest.
But for now, we have to spray and pray!
I recommend liquid concentrates for weed control. You mix these into water in a pump sprayer and blanket spray or spot spray the weeds/lawn.
I recommend mixing this way because I believe this is the most effective way to apply selective post emergent weed controls. This opposed to granular “weed-n-feed” products that rely on granules sticking to leaves or being watered in.
Mixing your own and applying directly ensures the target is hit!
Additionally, I want you to get comfortable with mixing and applying lawn products.
Eventually, you may want to tackle an application of liquid fungicide, insecticide or pre-emergent. These are definitely applications that require a bit of experience and precision and shouldn’t be attempted if you are brand new.
However, spraying a few weeds with over-the-counter weed controls like the ones we find below is a great way to learn.
You gain experience in this area first, learn your equipment, and then you are ready for something a little more advanced. That said, here are the weed controls that I found at my local Home Depot and some of the characteristics about them.
First 2 things to look for when choosing a post-emergent weed control:
- Make sure it is “safe for lawns” or “kills weeds, not lawns” or “weed killer for lawns”
- Make sure your particular grass type is listed on the label as ok to use. This is more of a concern with warm season turf as it varies in tolerance. Cool season turf like Kentucky Bluegrass, rye and fescue are all mostly tolerant of the same products.
From there you can make a choice, here are a few I found and what I think of them:
Image Kills Nutsedge
St Augustine, Bermuda, Zoysia, Centipede
Active Ingredients: Imazaquin 3.3%
Bottle Cost: $19.97
Bottle Size: 24 oz concentrate
Mix Rate: 2.5 oz /1-gallon water
If you have sedges or kyllinga this is a good choice. It will do some damage to other weeds we face here like dollar weed, but it’s really a one-trick-pony product aimed at nutsedge.
I highly recommend you only use this as a spot spray and don’t blanket spray with it. Also, only put this product on actively growing turf and is vigorous and not under stress or dormancy.
Image Southern Lawn Weed Killer
St Augustine and Centipede is what this is marketed to on the package but when you read the label it’s ok for Zoysia, Bermuda, and Bahia too.
Bottle Cost: $9.97
Bottle Size: 32 oz
Mix Rate Varies - mid rate is: 6.4 oz/gallon/1,000 sq ft
Cost per 1,000 sq ft: $1.99
Cost to Blanket Spray 5,000 sq ft: $9.97
Image Southern utilizes multiple active ingredients with 3 sites of action (3 different group herbicides). If you want to get in depth on “sites of action” and “modes of action” in herbicides, check out this chart here.
Either way, this is the best herbicide I found on my visit to the store (my opinion). They market it for St Aug and Centipede but it will do well on Bermuda, Zoysia, and Bahia too which are all on the label as “ok.”
Also comes in a ready to spray hose end option - for $11.97 and also covers 5,000 sq ft. This would make a good option if you did not want to go mixing.
This Image herbicide is a knockoff of Avenue South. Avenue South is a very popular professional weed control formulation from PBI Gordon.
Many of you remember from a video last year where I met with some folks at the GIE+Expo trying to convince them to bring their quality pro weed control to the DIY market by offering a smaller bottle size… this is them.
I had this sample and thought “gee how hard would it be to put a UPC code on this, update the label for retail sales, and offer it to homeowners?”
This would solve a lot of the challenges we have with professional products - that being that they only come in large quantities designed for pros using wide app equipment or treating multiple lawns.
This little sample size is 8 oz. The mix rate is 1.5 oz/gallon/1,000 sq ft.
That means this small 8 oz bottle can cover 5,333 sq ft. That’s plenty for someone with a smaller lawn who only want to spot spray or zone spray. If they made this little bottle affordable, we could get it shipped right to you, cheap!
My pitch to them was that if they’d make the effort to offer this smaller quantity to you guys, that you’d very quickly outsell the pros.
I firmly believe that too. Anyway, my pitch didn’t go anywhere and I never heard back. Thanks PBI-Gordon!
So for now, this product from Image is your best bet. It’s got the very same active ingredients, just in lower percentages to allow you some fudge factor. I highly recommend it if you can get it.
Ortho Weed B Gone Northern & Southern Lawns (Ready To Use formula)
“Ready to Use” means you just hook it up and spray - no mixing. Not easy to blanket spray this way but it’s an option for learning can work if you only have a few spots to hit.
Centipede, Zoysia, Bahia, Bermuda. (Cool season grass ok too)
No Floratam St Augustine - if you live in Florida, you probably have Floratam so don’t use this!
Mode of Action:
All 3 ingredients are auxins. (all group 4)
Bottle Cost: $11.97
Bottle Size: 128 oz (1 gallon)
Mix Rate: n/a
If you are only fighting a few weeds here and there, this is a great option because there is no mixing to do. Lots of you with thicker turf will not see tons of weeds and so this can be a good option for the few that do come through.
In order for weed controls like these to work, the target weed must be actively growing. That means night time temps (air temps) above 50F.
If you have night time temps dipping into the 40s, that will all but stop weeds from growing and without that, the active ingredients in the weed control cannot make their way through the plant and they very quickly can lose effectiveness.
So even if you see weeds in your lawn, and you have the right product to go after them with, you need to wait until those outside temps are staying above 50F at night.
Even if the day temps are higher, it’s the night temps that matter most because the weed growth will shut down and your product just goes to waste.
More Tips This Week
If you are looking for more great lawn tips this week, John Perry has been doing a series on weeds in the lawn that is very good worth the watch. Catch those 3 episodes here.
Thanks for reading, I hope you found this email helpful - I’ll see you in the lawn!