Monterey Mark-It Blue - Spray Solution Colorant Chemical Marker Dye for Insecticide, Herbicide, and Fungicide, 8 oz

I have used this product with a herbicide for years. It is a great aid in showing where sprayed and/or missed. Easy cleanup if I get it on my hands, I just spray window cleaner on my hands and it washes away. It last long enough on the ground. Good product, good value and I will continue to use it

Works as described

received fast be careful pouring can get messy wear gloves

I now can tell what and where i sprayed. No double spraying or missed areas

This product works as intended when I became able to use it. I was unable to get the cap to unscrew. It's one of those push-down-and-turn types. Well, I was pushing down so hard the container started to buckle. The teeth that engage the lid would simply slip off. Gave up because who wants blue everywhere. Ended up cutting a small hole at the top of the plastic bottle and pouring most of it into glass bottles I happen to have (wearing gloves of course). Thus, the three stars.

We have been using this with our Bermuda grass and herbicide to be able to get rid of the Bermuda grass in the yard. The blue colorant allows you to clearly see what you have sprayed and what you haven't.I recommend wearing gloves because this stuff is very blue and if you get it on your fingers you're going to have blue fingers.Whenever you spray anything or use any type of product be sure to wear the proper safety gear such as a pair of rubber gloves and some safety glasses.

After reading the reviews for this product, I was tossing the dice when I decided to purchase it. Fortunately, Monterey's Mark-It Blue Spray Solution exceeded my expectations. Following the dilution instructions on the bottle, the blue was plainly visible when I sprayed my vegetable garden with Neem oil solution. I mean it really stood out on my deep green tomato plants. I didn't stand out there to see how long the blue lasted but I could still see it on my plants the following day. Rain or water from the sprinklers does wash most of the blue from the plants but since I spray all my plants during one sweep, that's not a problem. In fact, I was relieved because I had a lot of overspray that hit one of my walls along which I had placed a row of potted tomatoes that grew in excess of eight feet tall. After a solid rain storm, little to no trace of blue could be seen on the white walls. When it gets on your hands, and it will, it may require you to jump into the shower to scrub it all off but it will come off fairly easily. I do have to take a brush to the tips of my fingers to get it out from under my fingernails. I also noted that spots on my patio where I spilled some of it is still blue, over two weeks later so it doesn't readily fade away unless you wash it off. I do think this product is a bit pricey and prospective purchasers should do an analysis as to whether using it results in cost savings compared to the cost associated with inadvertently re-spraying the same spots. I suspect reducing the ratio of Mark-it Blue to water/spray content in an effort to economize contributed to other reviewers' who had difficulty seeing the blue. I haven't determined yet whether there's any negative effects on the blossoms that the blue hit but if none, I plan to purchase again and can recommend this product to other gardeners.

Wear gloves and works in open area - can be messy. But it works, soon fades away.