Homemade and natural sprays can keep pests at bay without exposing ourselves, our pets, or the beneficial soil microbes to toxic chemicals. They are easy to make and inexpensive.
Plant combinations deter many pests. Marigolds ward off nematodes, for example, and the scent of garlic deters cabbage looper caterpillars.
Neem Oil
A staple in many gardeners’ tool kits, neem oil provides a safe alternative for those who prefer not to use synthetic chemical pesticides. When sprayed on leaves, neem oil dries and suffocates insects while disrupting their ability to eat and reproduce. It also interferes with their hormones, causing them to stop laying eggs and growing. Neem oil has been shown to be effective against a wide variety of garden pests, including caterpillars, fungus gnats, squash bugs, cabbage maggots, nematodes, locusts, mites, and other damaging insects.
Purchase a neem oil product formulated for gardening and follow its directions carefully to mix it. Some are ready-to-use sprays, while others are concentrates that need to be mixed with water and ordinary dish soap before applying. If using a concentrate, always wear protective gear and read the label to ensure proper dilution and safety precautions.
Spray your plants thoroughly with the neem oil, ensuring to cover the undersides of leaves where most pests hide and lay eggs. Wait several days before checking your garden for pests, and reapply as needed until the infestation is under control. Applying neem oil on a regular basis can prevent insect infestations from starting in the first place.
Neem oil is available in a variety of forms, from dust and granules to wettable powder and cake. It can be applied as a dormant spray to kill overwintering pests or as a foliar spray to ward off insects during the growing season. Be sure to apply it on a warm, dry day and to only those parts of your garden that are affected by pests. The neem oil must soak into the leaves and soil to work, so you may need to repeat applications every few days to see results.
Garlic
Garlic isn’t just good for your breath; it’s a natural pesticide that can help you get rid of unwanted critters and cure fungal diseases in the garden. Its pest-repelling properties are due to the allicin and sulfur compounds that it contains, which can effectively jam up insect sensory receptors. The best part is, you probably already have garlic in your kitchen!
You can use a garlic spray to deter aphids, caterpillars, flies, moths and mites, as well as slugs. It’s also effective against a number of animal pests, including rabbits, squirrels and deer. I’ve even found that mixing it with red pepper flakes makes an excellent deterrent against rabbits and moles!
Some people use garlic-infused water to treat fungus problems, such as powdery mildew and downy mildew. You can also use it to prevent rot on leafy greens, such as spinach and lettuce. Garlic can be sprayed directly on leaves, or diluted into a spray bottle and applied to the soil around plants.
Garlic is a great alternative to toxic garden products, especially for organic and ecologically-friendly gardeners who prioritize environmentally friendly gardening practices. It is also more affordable than many commercial products available in the garden center.
Chili Pepper
According to Momooze, the capsaicin in chili peppers acts as a natural deterrent to many insects. It also has some insecticidal activity, which means it can kill or slow the life cycle of certain pests. It is a common ingredient in commercial and home preparations of natural insecticides. It does not meet any of the highly hazardous pesticide (HHP) criteria but has been classified as a possible human health concern due to its potential for causing skin irritation and severe eye damage.
When mixed with water, chile peppers can be used as a spray to repel insects, such as beetles, fruit flies, and mosquitoes. It can also help ward off diseases triggered by certain types of fungi. As a bonus, it can be made using ingredients already in your kitchen. It’s a cost-effective solution that doesn’t strain the budget and promotes an eco-friendly gardening practice.
It’s important to remember that a cayenne spray is quite hot and can burn the skin and eyes of people and animals. Therefore, it should be applied sparingly and kept away from children and pets. For more permanent protection, consider enclosing prized plants with wire screening or mesh.
Another easy and inexpensive way to repel bugs is to apply a thin layer of garden-safe diatomaceous earth. This works by attracting insects to the surface where they die of suffocation. It’s a great organic alternative to chemical bug killers and will not harm beneficial soil critters or pets. It’s available at most garden centers and online.
Dish Soap
Garlic sprays contain diallyl trisulfide and diallyl disulfide, compounds that repel or kill aphids, whiteflies, beetles and other garden pests. It is also safe for use around tomatoes and other edible plants. To make a garlic spray, crush some cloves of garlic and add them to some mineral oil. Allow the mixture to steep for 6-8 hours before straining out the cloves. The resulting liquid will last for a while in the refrigerator and can be used to spray plant leaves.
Many responsible gardeners choose to use summer oil or a dilute soap solution over more toxic chemical sprays, but it’s important to note that these solutions only work on insects that come into direct contact with them. In addition, they can disrupt pollinator activity by stripping the natural oils and waxes from the leaves of a targeted plant.
These low-toxicity options are effective against most soft-bodied sucking insect pests, including aphids, mealy bugs, white flies and spider mites. They also don’t create resistance in these pests and do not harm beneficial insects.
It’s best to apply the soap spray in the early morning or evening, as cooler temperatures slow the evaporation rate and will favor better control of pests. It is also important to spray only the target plant, as overspray can damage the leaves and stems.
If you are concerned about mammal pests such as bunnies, deer and squirrels, try a spray made of equal parts red pepper and water. The capsaicin in the pepper will irritate these animal pests and encourage them to seek food elsewhere. In addition, it will not cause any toxicity issues for humans or mammals. It’s always important to remember that nature does a great job of maintaining balance and that if we are careful and thoughtful in our gardening habits, we can help preserve the natural predators, prey and pollinators that keep the garden in equilibrium.
Essential Oils
While the idea of putting essential oils in the garden may seem counterproductive, it actually works well as a natural pest control solution. The oils can be added to a spray or directly into the soil. They work by blocking the pests’ pores, causing them to suffocate. This method is especially effective for flies, gnats, aphids, squash bugs and mites.
Another safe way to kill pests is by sprinkling food-grade diatomaceous earth over the ground or on plants. The DE contains small sharp edges that cut into the insect’s exoskeleton, causing it to dehydrate and die. This is a great option for controlling slugs and snails. However, the DE needs to be dry in order to be effective, so it must be reapplied after rain.
Biological pest control is also a good choice for dealing with garden pests. Some organic options include the use of beneficial insects such as ladybugs and lacewings to feed on aphids, which are a common garden pest. These insects can be purchased from online catalogues. Other methods of biological pest control involve introducing bacteria, such as Bacillus thuringiensis, to the soil. This is controversial because it is used in GM crops, but it is also effective for killing many types of pests when sprayed on plants.
Preventing garden pests is far easier, and less costly, than dealing with an outbreak of pests after they appear in the garden. By using a combination of the prevention tactics listed above, you can strengthen your garden ecosystem so that it is able to better withstand pest infestations. If you do have a pest problem, it’s best to focus on removing the infested plant and using nontoxic methods for pest control.
