








🔵 Spray Smart, Save Big—Mark Your Lawn Like a Pro!
PetraMax Blue Herbicide Lawn Dye is a 3X super concentrated blue spray marker designed for fertilizers, herbicides, and weed killers. It provides a highly visible application indicator that fades naturally within 24-48 hours, preventing over-application and missed areas. Compatible with all major herbicides, it ensures efficient, safe, and eco-friendly lawn care for both home and commercial use.



P**M
As advertised and described, but good quality.
Top quality blue dye. Perfect what what is intended to accomplish, shows where you already sprayed so you don't waste time, money, and weed killer. The blue washed off my skin in the shower that night, where I accidently made contact with it.
M**K
Recommended
This works in my cart sprayer great. A little goes along way to see spray lines. Wouldnt recommend for a backpack sprayer as it clogged the outlet. Getting ready to purchase more as I am almost out.
D**Z
Works great, bottle needs some work
If you follow the directions, this produces a very clear blue color, even in the sun, wherever you spray. Super useful so that you don't overspray lawn chemicals. It lasts for a few days and then completely disappears which is exactly what you want. Since you use so little, it seems like a good value for the quality product you get. So far, I've used it in two different sprayers and after a quick rinse, no significant leftover blue color in the sprayers which was nice.I would love to see:- A better bottle: If you tip this on the side, it seems to come out a bit. That means, blue hands as you handle the product and you MUST store this bottle up right. Good luck if it tips over in your shed. From my hands and my shirt, I didn't have too much trouble eventually getting the blue out, but I would suggest wearing your "this shirt is already messed up so I use it for gardening" shirt. In general, clothes you don't care about too much just in case it doesn't come out of your specific fabric.- A built-in measure device: honestly I started with a plastic spoon but now just eyeball it. You can always add a tad more as needed.
J**H
Seems to Work as Advertised
I am happy with results. My previous dye was purchased at a popular Landscape supply store and it was okay. Thing to note is this, there is a difference in color intensity depending on whether you're spot spraying or doing full yard spray. For instance, when spot spraying, using 1/6 oz PetraMax to 1 gallon water works just fine. But if you're doing a whole yard spray with say Pre-emergent, then I will use at least 1/8 oz per 1 gallon of spray. This is not a ding on PetraMax, it just goes with the fact that my large area spray uses less water per square foot, thus less dye.
J**M
IT WORKS!!
I reviewed a lot of dyes and decided on this one. Wow, I had no idea it worked that well. When they said it will stain (not the weeds), anything else; it could not be a more true statement. I didn’t listen and yes, it stained my pants, but that was my fault. As far as the weeds, I mixed the suggested product to weed killer and it worked way beyond what I imagined. The second batch I made used less product and worked just as well. If you are trying to decide on a color product, look no further. This stuff really works and will last a long, long time. I will definitely purchase again when I need to. Thanks.
R**T
Works great if mixed.
Bought their sprayer on Amazon deal days. All the liquid products I’ve tried have worked great. The blue isn’t consistent coming from the tank. Starts out very dark blue and it quickly disappeared. Then it still had residual blue the next 4 uses if the sprayer regardless of rinsing it out after each uses. Won’t be buying again.
R**J
Great Product!
Great Experience!The item arrived exactly as described and right on time. Shipping was fast and the packaging was secure and professional, ensuring the product arrived in perfect condition. Everything went smoothly from start to finish. Very satisfied with the overall purchase experience!
S**S
A Little Goes A Long Way
Very concentrated - a little goes a long way. Just took a few drops to provide enough color to see where I'd sprayed. My first batch, I used too much and places in my yard were blue for over a week. That's user error, though, so no deduction for that. LOL. Recommended.
Trustpilot
1 day ago
1 week ago