As a professional landscaper using all-organic techniques, I’ve tested numerous safe weed killers to find the best organic weed sprays available.
With all weed killers, you’ll want to be careful not hit your good plants or yourself with spray drift. Even chemical weed killer like Roundup can’t distinguish between good and bad plants, and while safe weed killer doesn’t cause cancer or disrupt your hormones like many chemical herbicides have been shown to, it can be harmful if you get it in your eyes or mucus membranes.
Anyway, here are two of my favorite options for safe weed killer.
Weed Pharm, Safe Weed Killer Made of Vinegar:
Weed Pharm is a fast-acting safe weed killer that is one of the most effective organic weed sprays. It works by burning off the waxy protective coating on leaves so that the plants’ cells can no longer hold in water. The weeds wilt and shrivel within a few hours on a warm day.
Weed Pharm isn’t made of home-strength vinegar; rather this safe weed spray is made from a highly concentrated form of vinegar. Acetic acid is the active ingredient that harms the weeds, and normal vinegar has about 4% acetic acid content, while Weed Pharm has 20% acetic acid content.
Weed Pharm is made from food-grade ingredients and can be used as a safe weed killer in vegetable and landscaped beds. Do not spray vinegar-based weed killer on concrete, stone, or other patio surfaces unless you’ve spot-tested first to make sure it won’t stain or bleach the surface.
Injecting Taprooted Plants With Weed Pharm Safe Weed Spray:
You can also use Weed Pharm to get out plants with stubborn taproots that are planted in places you don’t want to spray. This is helpful if you get a dandelion growing in the middle of a good plant, or get one growing in your lawn that just won’t go away. What you do is inject the Weed Pharm into the base of the dandelion using a needle-less syringe like you’d use to give pets medicine by mouth (I got mine at my local pet store for $1.50).
It takes about two weeks, but since dandelions have a hollow taproot, if you fill that taproot with industrial-strength vinegar it pickles the taproot from the inside out and kills it permanently without harming your good plants.
Nature’s Avenger Organic, Safe Weed Killer Made of Citric Acid:
Nature’s Avenger Weed Killer works in a similar way to Weed Pharm in that it kills weeds safely by burning off the waxy cuticle that allows plant cells to hold in moisture. It’s basically a “chemical” burn, although of course citric acid is found naturally in oranges and other citrus. This is why it’s so important to wear eye and other protection when spraying even organic sprays. It doesn’t cause the horrible long-term hormonal disruptions that chemical weed killers do, but it’s still wise to take precautions.
Nature’s Avenger Organic is a safe weed killer for use in vegetable gardens, landscaped beds, and anyplace else you have unwanted weeds. The company does not specify that you must spot-test first in patio or hardscape surfaces, so this is a safe weed killer to use on hard surfaces, too.
Want to learn more about safe weed killer? Check out my eBook Guide to Organic Weed Control, in which I cover every type of preventative weed control tactic, a number of little-known strategies for combating weeds, and discuss the many kinds of safe weed sprays and how best to use them in every type of gardening situation.