Herbicide - Organic Herbicides

Organic Herbicides

Recently, the term "organic" has come to imply products used in organic farming. Under this definition, an organic herbicide is one that can be used in a farming enterprise that has been classified as organic. Commercially sold organic herbicides are expensive and may not be affordable for commercial farming. Depending on the application, they may be less effective than synthetic herbicides and are generally used along with cultural and mechanical weed control practices.

Homemade organic herbicides include:

• Corn gluten meal (CGM) is a natural pre-emergence weed control used in turfgrass, which reduces germination of many broadleaf and grass weeds.
• Spices are now effectively used in herbicides.
• Vinegar is effective for 5-20% solutions of acetic acid, with higher concentrations most effective, but it mainly destroys surface growth, so respraying to treat regrowth is needed. Resistant plants generally succumb when weakened by respraying.
• Steam has been applied commercially, but is now considered uneconomical and inadequate. It kills surface growth but not underground growth and so respraying to treat regrowth of perennials is needed.
• Flame is considered more effective than steam, but suffers from the same difficulties.
• D-limonene (citrus oil) is a natural degreasing agent that strips the waxy skin or cuticle from weeds, causing dehydration and ultimately death.
• Saltwater or salt applied in appropriate strengths to the rootzone will kill most plants.
• Monocerin produced by certain fungi will kill certain weeds such as Johnson grass.