Selective weed sprays can be quite complicated and this is especially true when using them for the first time.
I have seen many clients and homeowners make big mistakes when spraying herbicides on their lawns. As a licensed spray technician with over 10 years experience in lawn and garden care, I am going to help you avoid making the three most common mistakes other beginners have made.
1. Don’t use a cone nozzle, use a fan nozzle instead.
There are a few different types of nozzles used on pressure sprayers. The most common in lawn and garden care are cone nozzles and fan nozzles.
Cone nozzles are the most common type of nozzles. They are usually adjustable and can produce various types of spray from a wide, misting spray to a thin jet of water.
Whilst cone nozzles are the best option for garden bed spraying, they are not the best option for lawn spraying. This is because it is very hard to know the exact amount of product that is coming out of your sprayer and onto the lawn.
This can cause gardeners to unknowingly over-apply products to the lawn. In fact, the main picture of this article (above) is of a lawn that had a correctly mixed Bow and Arrow solution applied with a cone nozzle. The cone nozzle caused too much product to be applied per m2 which damaged the turf. It took about 3 weeks for this lawn to recover.
Fan nozzles are the type of nozzle you want to use when applying selective herbicides to lawns.
They deliver a flat, even, consistent spray. This means that they give even and consistent results. As a result, it is much harder to accidentally over-apply herbicides with a fan nozzle.
The photo on the right is of dual nozzles on a boom which is great for large lawns, but a single nozzle is going to be great for most residential lawns.
One more thing to know is that the different colours of nozzles indicate how fine or coarse the spray droplet size will be. Red, blue and yellow nozzles are all suitable for Bow and Arrow and Bin-Die
2. Don’t guess! Measure exactly how big your lawn is.
Borrow and Arrow, Bin-Die and other selective herbicides are only safe for lawns IF they are applied at the correct rate per square meter. Not knowing how many square meters your lawn is is a recipe for disaster.
I once had a client that made a big mistake with a similar broadleaf herbicide to Bin-Die and Bow and Arrow. Even though they mixed the correct ml of herbicide per litre of water, they made way too many litres of total solution. This was simply because they overestimated how much lawn they had (their estimate was almost double the actual lawn size).
They applied way too much solution to the lawn which yellowed 90% of the lawn within 24 hours. It took about 6 weeks for the lawn to fully recover. The exact same problem can happen with Bin-die and Bow and Arrow.
To measure your lawn area, the easiest option is to use Google Maps. Google Maps is quite accurate and does the math for you ( if you need a video tutorial on how to do this click here). However, sometimes newer houses and estates aren’t yet on Google and in these situations a measuring tape (or measuring wheel for larger lawns) and a calculator will be needed.
Once you know how much area you, have you can read the label to work exactly how much product and water you need.
3. Use 2 sprayers; 1 for the lawn, 1 for the garden.
It is an unfortunately common mistake: someone uses one sprayer for both selective and non-selective herbicides; they forgot which herbicide is in the sprayer and applied the wrong product and accidentally killed their lawn.
This is exactly what happened with this buffalo lawn pictured above. The homeowner accidentally applied glyphosate to their lawn due to only having one sprayer. This killed areas of the lawn. Due to the accidental spray happening in winter when buffalo is very slow growing, it took a bit over 6 months for all the dead patches to fully recover.
If you are going to be spraying herbicides on your lawn, don’t cut corners. Buy a dedicated sprayer for lawn-safe products and a dedicated sprayer for your garden weed killer. Use a Sharpie and big writing to clearly identify which sprayer is which. Some people will even buy two different brands of sprayer to make it more obvious.
If rinsed between uses, your dedicated lawn sprayer can be used for liquid fertilisers and pre-emergent herbicides too.
These three simply tips will help you avoid a lot of mistakes others have made when spraying herbicides.
- Use the correct nozzle
- Know how exactly much area you are spraying
- Use a dedicated sprayer for lawn-safe products
Here are two more articles that can be very helpful when applying Bow and Arrow and Bin-Die
If reading this seems like too much effort and you would simply prefer to have a professional take care of your lawns and gardens, contact Silverstone Gardening. We have several licensed spray technicians who know how to identify and control even the most difficult weeds.