Tineke Stoffels mentioned this plant spray on our last garden group meeting. She has used this spray last summer, it was very effective against lice and spider mite. She even sprayed her Buxus with the mixture and had no problems with the small caterpillars that devour the Buxus before you realise they are there.
The recipe below mentions a blender, no need, she chops up the ingredients and puts it into a used plastic milk bottle, adds the water and screws on the top. She leaves it to marinate for at least 24 hours. After straining the mixture, Tineke adds a dash of washing up liquid, she finds the spray clings better to the plant.
How to Make Onion Juice for Plant Spray
A blender offers a convenient means to puree onions and other spray ingredients.
Garden crops and ornamental plants throughout the landscape are potentially bothered by many different types of destructive pests. Rather than rely solely on commercially available or synthetic pest control products, you may opt to create your own pest-repelling plant spray. One potential effective ingredient in a homemade pest spray is onion, which has a strong odor offensive to many pests. Combining an onion with garlic and pepper to make a spray further increase its effectiveness against pests that chew on plant leaves or suck out plant fluids./
- Blend about six cloves of garlic, one large onion and a tablespoon of cayenne pepper or two whole peppers together in a blender or food processor.
- Combine the blended onion, garlic and pepper with a litre of water and let the mixture sit in a refrigerator for at least 24 hours.
- Pour the mixture through a strainer or cheesecloth into a jar to separate the solid mash from the liquid.
- Bury the separated solids shallowly in areas of your garden or yard near plants that are particularly bothered by pests.
- Pour the onion solution into a spray bottle
- Spray pest-infested or vulnerable plants thoroughly with the onion spray.
- Store any unused spray in the refrigerator. Use it within two weeks, spraying the plants every few days and following any rainfall or overhead irrigation.
Things You Will Need:
Garlic cloves (at least six)
Cayenne powder or one or two peppers
Strainer or cheesecloth
Biodegradable dish soap
Add about a tablespoon of biodegradable dishwashing liquid to the already-steeped spray solution to increase its effectiveness against certain pests.
Test any homemade pest spray on a few leaves in an inconspicuous part of the plant and monitor these leaves for any injury caused by the spray for a day or two before treating the entire plant.