What organic options exist for controlling weeds in my vegetable garden?
Mechanical control of weeds through hand pulling and cultivation as well as the use of mulches and other cultural control methods to suppress weed growth are all effective organic options for weed management.
Pouring boiling water on weeds can be used especially in situations where other plants are not nearby. Be careful to not splash or burn yourself with the boiling water and remember the boiling water will kill both weeds and desirable plants. A tea kettle is often a good way to safely and precisely apply the boiling water directly to the weed. Use plenty of water and plan to retreat 7-10 days later as one application rarely kills the entire plant, especially deep-rooted weeds.
Organic herbicides can also be effective, however, all of them act as non-selective herbicides, meaning they kill or damage any plant part they touch. Many organic herbicides use one or more of the following active ingredients: acetic acid, citric acid, clove oil, lemon grass oil, d-limonene, and ammonium nonanoate, among others. Most organic herbicides work as contact herbicides, killing the leaves and stems, but not being translocated to other parts of the plants, such as roots. Often, multiple applications every 2 to 3 weeks are needed for complete control. Organic herbicides are more effective on younger, smaller weeds than larger more established ones and should be applied at a higher volume than most conventional herbicides, thoroughly soaking leaves to point of run off. Always follow label directions on all herbicides. Even organic herbicides can harm desirable plants or people when used inappropriately.