When pests come a-crawling, give one of these effective options a try
While every gardener loves to watch the bees buzz, some bugs in the garden are not as welcome, as they can wreak havoc on your perfectly pruned perennials. Luckily there are a variety of homemade insecticides and bug repellents you can use to try to keep those unwelcome insects at bay. Here are 11 of the most effective natural and DIY pesticides for your garden.
General Tips for Using Natural and DIY Insecticides
There are many benefits to using a natural insecticide or one that you whip up using ingredients you already have at home. While many commercial pesticides are effective against insects, they sometimes kill off beneficial insects and can be harmful to pets and children. However, before getting into the best kinds to try, you should know a few quick tips for using insecticides.
Never apply any insecticide to a stressed plant.: Avoid spraying burned leaves, and ensure all plants are well watered.
Remove as many of the diseased leaves as possible before spraying. If the leaves still look healthy, treat them individually.
It’s best to apply either in the morning before the sun hits, or early evening when the sun has faded, to eliminate the chance of burns.
Always wear gloves and a face mask when applying any pesticide in your garden, even a gentle one.
Keep pets away from the area during application and until the insecticide has thoroughly dried, even if you use something like dish soap.
Before applying to an entire plant, it is advisable to test spray a few leaves with the solution you have made, wait 48 hours, and inspect for damage. If the leaves are burned or browned, dilute your solution and run another test.
1. Dish Soap
Combats: aphids, beetles, whiteflies, mites
One of the more common household ingredients for blasting bugs is dish soap. You can make a spray using this kitchen sink staple, but you need to be careful about the ratio of soap to water. Too much soap will ruin your plants.
Use mild dish soap or castile soap.
Add 1 and a half teaspoons of soap per 1 quart of water.
Mix this in a larger container and then pour it into a household spray bottle to ensure you are getting the ratio correct.
Spray the leaves where insects appear. Cover the top and bottom of the leaf.
Never apply during the heat of the day or when plants are in direct sunlight (choose early morning or evening instead).
Repeat the process every four to seven days, and after heavy rain, until you start to see an improvement.
Don’t forget to test first.
Use a few drops of dish soap in water in a small bucket or container and place this below your plant to collect bugs like beetles or squash bugs. The soap in the water will coat their bodies, making it impossible for them to fly out. The ratio of soap-to-water is less critical here, as it’s not being applied directly to the leaves of the plant itself.
2. Vegetable Oil
Combats: aphids, beetles, whiteflies, thrip, mites
Similar to soap spray, a vegetable oil insecticide is a good way to get rid of annoying bugs. The soap and oil combo coats the insects’ bodies and helps banish them from your beloved garden.
Use 1 tablespoon of mild soap (like dish soap or castile soap) to 1 cup of vegetable oil. Mix well.
Add 2 tablespoons of the oil mix to 1 quart of water and pour into a spray bottle.
Spray the top and bottom of each leaf where the insects are dwelling and the stems if needed.
You’ll probably have to stop and shake the mixture a few times during application to make sure the soap, oil, and water are mixed.
Never apply during the heat of the day or when plants are in direct sunlight (choose early morning or evening).
Reapply every four to seven days and after heavy rain.
Don’t forget to test first.
3. Diatomaceous Earth
Combats: snails, slugs, ants
This powdery substance is ground silica produced from the fossilized skeletons of tiny marine organisms known as diatoms. The powder itself damages the protective coats of ants, slugs, snails, and other invertebrate pests.
Be sure to use the horticultural grade—there is another type on the market used for swimming pool features and is much too harsh for your garden.
Always wear a mask and gloves when applying diatomaceous earth.
Follow the manufacturer’s instructions for distribution, but in general, you will put the powder around the perimeter of any garden bed you want to protect, as well as at the drip line of your plant.
To be more precise, use a paintbrush, small measuring spoon, or even a turkey baster if you are trying to get in cracks (to deter ants, for example). If you are applying over a large area, such as a lawn, use a flour sifter; just do NOT reuse the sifter in your kitchen.
You will need to reapply after rainfall or heavy dew.
Reapply every week.
Combats: aphids, leafhoppers, mealybugs, scale, spider mites, stink bugs, whiteflies, thrip
Pyrethrins are derived from the flowers of the Dalmatian chrysanthemum or Pyrethrum Daisy (Tanacetum cinerariifolium). The spray is widely available at any garden center, or, if you’re feeling crafty, you can try making your own:
Wearing a mask and gloves, use a blender or food processor to grind dried flower heads into a powder. (Just be sure to wash it well before making your daily smoothie).
For every half cup of dried flowers, add 4 cups of water. Include a few drops of soap to help the mixture stick.
Add this mixture to a spray bottle and apply to the tops and bottoms of infected leaves. For heavy infestations, spray the stems as well.
Pyrethrins break down in sunlight, so apply at sundown.
Don’t spray when the temperatures are above 85 degrees Fahrenheit.
Repeat once a week and after heavy rain until infestation seems to be under control.
Don’t forget to test first.
5. Hot Pepper Spray
Combats: spider mites, aphids, deer
Used most commonly to deter deer from eating plants, exercise caution with this one. If you’ve ever made a big mistake while eating wings, you already know that hot peppers can cause burning and discomfort, especially in the eyes. Always wear gloves when you prepare or administer this solution, and avoid applying on a windy day. You do not want a cloud of pepper spray blowing back into your face.
Wear gloves and a mask.
Consider mixing this one outside if possible.
Combine 2 tablespoons of red pepper, cayenne pepper, or paprika with 1 gallon of water. Add six drops of mild dish soap to help the pepper solution bind.
Pour the substance into a household spray bottle. Make sure to label the bottle clearly.
Thoroughly saturate the plant on both sides of the leaves.
Do not apply during the heat of the day. Sundown is the ideal time.
Reapply every three to four days and after heavy rainfall.
Don’t forget to test first.
Combats: slugs, snails
A bowlful of beer in your garden will act as an attractant to slugs and snails: They can’t resist it and will fall into the bowl and meet their demise.
Make sure it’s deep enough to make sure they can’t just crawl out easily.
Place out in the evening and check each morning.
Any kind of beer will do: It doesn’t need to be the good stuff.
Be sure to supervise any kids or pets if you’re putting this out in the garden.
Refill as needed.
7. Beneficial Insects
One of the most sustainable ways to combat invasive, leaf-destroying insects is to introduce their natural predators. Plant native and pollinator-friendly plants, such as the pincushion plant (Scabiosa) and beebalm (Monarda), to attract insects that not only help your garden thrive but also prey on the bugs that damage plants. You can also add these beneficial insects directly into your garden.
Purchase beneficial insects at a garden center and release them into your garden.
It’s best to release insects first thing in the morning.
Aim to introduce these insects at least once every growing season, ideally in early spring.
Combats: slugs, snails, ants, flies
Use a simple vinegar solution to repel and kill insects in your garden, especially slugs, moths, and ants. Do not use industrial vinegar that has a higher (20% or more) concentration of acids, as it will ruin your blooms.
Use one part vinegar (apple cider or white) to three parts water to create a sprayable solution.
Add a few drops of mild dish soap to help the solution stick.
Add to a sprayer bottle and apply to the base of infested plants. Treat the leaves directly if heavily infested.
Use vinegar in place of beer to attract slugs and snails to their doom.
A concentrated spray (three parts vinegar to one part water) is used to treat weeds.
Vinegar is effective in repelling dogs, cats, and even coyotes.
Only apply vinegar solution in the early morning or at sundown. Too much vinegar will burn your plants.
Apply the solution every seven to 10 days.
Don’t forget to test the solution on a few leaves first.
Combats: aphids, ants, beetles, caterpillars, slugs, whiteflies
Not only can you plant garlic in and around vegetable garden beds to ward off bugs (and create delicious meals to boot), but you can also use it as an effective insecticidal spray. Buy concentrated garlic sprays at a garden center, or try making your own.
In a blender or food processor, finely crush six cloves of garlic.
Add 5 cups of water and four or five drops of dish or castile soap. You may also add a few drops of vegetable oil.
Strain this mixture through a cheesecloth or a very fine strainer to remove any large pieces. This strained mixture is your concentrate.
Store the concentrate for up to a week in a jar with a tight-fitting lid. When ready to use, dilute the entire solution with 3 cups of water.
Add this mixture to a household sprayer.
Coat tops and bottoms of leaves of affected plants.
Apply this solution every week or after periods of heavy rain.
Don’t forget to test a few leaves first to make sure your solution is safe for your plants.
10. Neem Oil
Combats: Aphids, beetles, leafhoppers, mites, mealybugs, caterpillars, scale, thrip, whiteflies
Neem oil is a natural byproduct of the Neem tree and is an effective insecticide against various garden pests. It is widely available at garden centers.
Neem oil comes in a variety of forms, including a concentrated oil and ready-to-spray. Always follow the manufacturer’s directions for precise mixing and application. Too much neem oil will burn your plant’s leaves, so run a test on a few leaves first if you aren’t sure.
Neem is used to control insects at stages of development, including larvae, so apply once during dormant seasons and then apply weekly or biweekly throughout the growing season.
Neem is also used as a fungicide to treat powdery mildew, rust, black-spot, and other common garden diseases.
11. Companion Planting
Just like your body, preventative care among plants is the foundation for having a healthy garden. One of the best (and prettiest) ways to do this is with plants that act as natural insect repellents, such as: