Should We Use Organic Weed Killer?
Organic weed killer or herbicide can be used in organic gardens to kill unwanted plant growth without introducing dangerous chemicals into your backyard. Many people will look for organic weed killer even if they do not have a 100% organic garden. In a vegetable garden, you probably do not want to spray a lot of unknown chemicals onto plants that you are growing for food. And even if you only have lawn and flowers, organic weed killer will usually be safer for pets. Do check labels, however, because ingredients can vary.
The word ‘organic’ has two different meanings. One is any substance that is carbon based. This includes virtually all weed killers. The other meaning is a product that can be used on land that has been certified for organic food production. This is what we usually mean when we talk about organic weed killer, and there are not so many of these products. So if you are buying a commercial weed killer, you will need to check that it is for organic land.
Herbicide (which just means ‘plant killer’) comes in two types. Selective herbicides kill certain plants only, for example, a broad leaf weed killer will kill clover, dandelion and similar weeds in a lawn without harming the grass. Non-selective herbicides kill all plants. These would not usually be used in a garden but you may have areas of the yard where you do not want anything to grow, for example on a gravel area.
Non-selective chemical weed killer that kills everything can be dangerous to use in a garden because it can be spread into other areas by rain and prevent anything from growing. The main organic version is vinegar, used in around 15% to 20% concentration in water. You can spray this over the unwanted plants during a dry spell and they should die off. The weeds may grow back but not so strongly. Repeated spraying will usually prevent regrowth in the end. Do not use on areas where you may want to grow other plants later.
A better solution for many organic gardens is to use a layer of felt or sheets of newspaper under the gravel or decking where you do not want weeds to grow. Or if you have a large area that you want to clear before replanting, you might use a flame gun to burn off the weeds. This should be done when they are wet, so that the fire does not spread.
A possible selective weed killer is citrus oil or D-limonene. Painted onto the leaves of unwanted plants, it strips them of their waxy protective surface. This will cause them to dehydrate and die. Be careful not to contaminated wanted plants with the citrus oil, because it will kill them too.
Some people are against the use of any type of weed killer in an organic garden. It is true that usually you can control weeds by hand. However, in some cases such as around paths or in large gardens this can be difficult. Organic weed killer can be a solution in these cases.
