The minerals in hard water can prevent the soap from dissolving, and this will make the spray less effective. [1] X Research source
Aphids Japanese beetles Spider mites Mealybugs Boxelder bugs Whiteflies Psyllids Cockroaches Young scales
Neem oil is a plant-derived insecticide that’s effective for controlling beetles, cabbage worms, beet armyworms, fungus gnats, and thrips. [4] X Research source The oil will also help the soap residue stick to leaves, insects, and eggs. Apple cider vinegar is effective at killing powdery mildew, which is a fungal disease that can affect many plants. [5] X Research source
To store leftover insecticide, transfer the mixture to an airtight container and store it at room temperature for up to a year.
Sweet peas Cherries Plums Portulaca Certain tomato varieties
If the leaves were damaged by the spray, dilute the solution and test it again. If the leaves are healthy, apply the spray to larger areas.
You can also add 4 cups (940 ml) of water to a pre-made batch of 2 percent soap solution.
Leave the spray on the leaves for a few hours.
If you find you still have bugs after a week, try the mixture with a different soap, or use a commercial insecticide instead.
Garlic contains sulfur compounds that repel a variety of insects. By adding garlic to your soap-based insecticide, you’ll be able to kill bugs and deter others from returning. If you don’t have a blender or food processor, combine the garlic and water in a mason jar and use an immersion blender to puree it. If you don’t have any blending equipment, mince the garlic with a garlic press or sharp knife.
Good soaps to control insects include liquid hand soap, castile soap, and liquid dish soap.
Leftover mixture should be stored in an airtight container in the refrigerator. Because this insecticide contains garlic, use leftovers within a week.
Be sure to wear gloves while handling hot peppers.
You can also skip boiling and let the mixture steep for 36 to 48 hours. [20] X Research source
If you don’t have a blender, you can try to mash the onion by hand with a vegetable chopper.
If you do not have a blender, you can stir the ingredients together in a large bowl.
A tomato is a member of the nightshade family and produces a natural repellent to aphids
Along with using insecticide to treat caterpillars and beetles in the garden, you can also remove them by hand. Pick the bugs off the plant with your fingers and drop them into a bucket filled with soapy water. [30] X Research source
When treating for thrips and mites, spray foliage, buds, and the soil around the plant. [31] X Research source Thrips are a tiny winged insect with a slender body.
These bugs can be treated by spraying the plants with water, but use insecticide for more severe infestations. [32] X Research source
These problems are not caused by insects, so they can’t be controlled with insecticide. The best way to control these issues is to prevent them by watering plants from below so the leaves don’t get wet. Remove any leaves that show signs of infection.
