Effective Organic Weed Killer Recipes That Are Eco Friendly
It is possible to make your own organic weed killer at home. I prefer it when you use organic herbicides because they are friendlier to my soil-dwelling friends and me. Sure, you want to kill the weeds sprouting up all over the garden, but you want to keep alive the friendly critters that make the soil a nice place for plants and
How Weed Killers Work
Weed killers are herbicides. That literally means “plant death.” Herbicides and weed controls work in a number of different ways, with each one affecting the plant’s physiology differently. While I strongly object to poison chemicals in the garden, you should still understand how they work.
Systemic weed killers are taken into the plant and kill the plant from the inside out. The synthetic chemical glyphosate, which is often sold under the brand name “Roundup” is a systemic herbicide. You may not notice your plants being affected until several days after you have treated the plants.
Other herbicides are contact herbicides, and they kill the part of the plant that they touch, immediately. The problem with contact herbicides on well-established weeds is that often only the top of the plant is killed, and a well-established plant has enough reserves to re-sprout.
Whether using a natural weed killer or a synthetic weed killer, it is important to know how the treatment will work in order to apply it correctly and get the best results.
Pre-emergence and Post-emergence Weed Control
Another aspect of weed control that you need to understand in order to be successful is whether you want to accomplish pre-emergence or post-emergence weed control. Pre-emergence weed control is used to control sprouting of weed seeds, or to kill weeds just after they germinate. “Weed and Feed” mixes sold at hardware stores and garden centers include pre-emergence herbicides.
Since a pre-emergent prevents seed from germinating, it should only be used on around permanent plantings, on lawns or where you only intend to transplant established starts. Never use it where you plan to sow seeds, now or at any time in the future.
The organic pre-emergence herbicide or natural weed killer is corn gluten. It is much easier to get this commercially than it was a few years ago. The corn gluten can take a few years to work completely, but it is worth starting a regimen of it so that you can gradually transition completely to it. Corn gluten is an eco friendly alternative to poisonous chemical pre-emergent herbicides.
Post-emergence weed control is control of weeds after they have become established. This can range from a plant with just a few leaves, only a few weeks old, to well-established weeds. Unfortunately, it is much more difficult to kill well-established weeds organically. So, early use of organics is important.
Home-Brewed Organic Weed Killers
Most homemade organic weed killers use vinegar (acetic acid) and sulfur. If you are growing asparagus or celery, and will be growing it more or less forever in the same spot, you can also use rock salt. Otherwise, stay away from the salt. Here are a few home brews for natural weed control. (Some do not involve more than one ingredient. Nice!)
- Hot Water: That is correct—pour hot water on your plants and they will die quickly.
- Bleach: Bleach kills almost everything, including plants. To use it as a weed killer, put a 50% bleach solution in a spray bottle and mist the offending plants.
- Rubbing Alcohol: This one acts as a contact herbicide, burning the leaves of any plant it touches. It does not kill the entire plant, though. Vinegar can be used for the same purpose.
- Soap: Spray a 50% dish soap, 50% water mixture on your weeds. You will suffocate them.
- Combination: Prepare a mixture of 1/8 soap, ½ vinegar and 3/8 water. Pour into a spray bottle and mist plants. The soap will help the vinegar “stick” to the plant, and the top of the plant will begin to die.
All these are contact herbicide recipes. There are, unfortunately, no systemic organic weed killers.
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