DIY organic pest control is a tricky beast but armed with the right knowledge, you should be able to eliminate any pesky critters that are hanging around in your garden.
That said, it’s best to exercise caution when handling toxic chemicals.
Professional pest exterminators have the skillset and experience that is needed to manage fast-acting and hazardous chemical products. However, the same products could prove dangerous in the average DIY-er’s hands, especially if they have pets or children. What’s more, conventional pesticides and herbicides could be quite harmful to both your garden and the environment.
Instead of dangerous and hazardous chemicals, use one of the many effective pest control method alternatives to rid your place of pests.
Here’s a look at some of the best organic pest control methods.
15 All Organic Pest Control Methods For Better Gardens
1. Floating Row Covers
Floating row covers keep out insects while letting in up to eighty percent of light. These translucent fabrics can be found in both the lightweight and heavyweight variety – use the lighter ones in the summer, and the heavier ones in the winter.
You can cut the material to the length you need, and then wrap it around your tomato cages, attach it to your support frames, or just lay it on top of your crops like a white blanket. Just make sure you secure the covers’ edges.
Floating row covers are great devices for plants in vulnerable stages, such as when they’re just seedlings, or when pest activity is rampant. Avoid using them throughout the lifespan of the crop if it needs insect pollination. They’re particularly effective against cabbage moths, aphids, flea beetles and other mobile pests.
2. Oil Sprays
After a direct hit, oil sprays will suffocate pests. During the dormant season, you can use dormant oils to kill spores and pest eggs on shrubs and branches. Summer oils are used on growing plants – these are relatively lightweight and refined, and evaporate faster than dormant oils to limit damage to the plants.
Never use oil sprays on plants that have moisture stress, and avoid spraying when it’s very hot. Before spraying a whole plant, conduct a test on a few leaves and wait for 48 hours to ensure there’s no discoloration or unwanted damage. You will also want to limit harm to beneficial insects by only spraying areas where you can spot pests. Oil sprays work best against mites, aphids, beetles, caterpillars, leafhoppers, whiteflies, thrips and leaf miners.
This is one effective pest control method you’ll need to use with caution since it’s somewhat toxic to most mammals. Rotenone is an organic chemical that occurs naturally within the stems and seeds of certain plants. Employ extreme caution when using this near a lake, pond or any other body of water, since it is quite toxic to fish. While the chemical is slow-acting and takes some days to work, it effectively kills off aphids, thrips, caterpillars that feed on leaves, and beetles on fruit and vegetable crops.
4. Pheromone Traps
Insects will often produce powerful pheromones in order to attract the opposite sex. These pheromones have been replicated in labs to produce special baits that act as warning signs a pest may be moving into your garden.
However, they’re not so effective as controls, since the traps tend to only attract male insects. When you first see pests in these traps, it’s an indicator you need to start control. This non-toxic pest control method works best against corn earworms, cabbage loopers, armyworms, cutworms, and tomato pinworms.
5. Neem Oil
Neem oil comes from a tree commonly found in South Asia and is used to inhibit insect growth cycles. Once ingested, it causes insects to grow slowly, and eat and molt less. This is an excellent choice for gardeners who want to reduce the number of potential pests before they become a headache.
It is most effective on young insects, and fast growers like Mexican bean beetles, squash bugs and Colorado potato beetles, as well as on aphids and caterpillars. What’s more, you can spray excess neem oil on vine crops to prevent powdery mildew.
6. Sticky Traps
Sticky traps are composed of stiff material in a specific color that is covered with a sticky substance. This pest control method traps insects attracted to that particular color. You’ll need to use a trap every five feet for efficacy, as well as make sure they’re clean. Yellow traps lure fruit flies, whiteflies, leafhoppers, midges, fungus gnats, winged aphids, and thrips, among others.
White traps attract plant bugs, whiteflies, flea beetles and cucumber beetles. Red traps prevent apple maggots, while light blue ones lure in flower thrips.
7. Insecticidal Soap
Make sure you don’t confuse this organic pest control method with herbicidal soaps, which damage vegetation. Insecticidal soap will dissolve insect cuticle when its liquid form physically comes in contact with insects. The chemical does not work once it dries.
Avoid harming beneficial insects with this, and use it with caution, since the soap can burn certain plant leaves. Before spraying a whole plant, conduct a test on a few leaves and wait for 48 hours to ensure there’s no damage. Avoid spraying when it’s very hot, and rinse off the soap within a few hours if there’s plenty of sunshine. These sprays are most effective against soft-bodied insects like aphids, mites, and whiteflies.
8. Bacillus Thuringiensis
This bacteria naturally occurs in the soil, and some varieties can be used to target particular insects. After a target insect eats from a plant that has been sprayed with the right BT, it stops feeding and dies in a few days. Bacillus Thuringiensis (BT) is usually sold as a liquid or a powder you add water to. Some of these products come in the form of granules or dust you sprinkle on the plants directly.
Each variety of BT will only work against a specific insect, but don’t make the mistake of spraying everywhere recklessly, since it could also prove effective against a different insect. The BT that kills cabbage loopers, for example, also kills off caterpillars of butterflies you may want in your garden. Make sure you only spray plants infested with pests.
BT is usually only effective against larval pests, which means you need to carefully time the applications. Once you see the larvae, cover the afflicted plants thoroughly using the dust or spray. Avoid spraying when it’s very hot in the day since sunlight reduces the bacterium’s efficacy. If there’s a severe infestation, you will probably have to reapply BT after a couple of days, since the bacterium breaks down within that time.
Never spray or dust this without wearing a mask and goggles – some people have allergic reactions to the bacterium.
The best part about BT is that it is only effective after ingestion, meaning they make for incredibly safe pest control. BT var. kurstaki is the most common bacterium variety and can kill many different kinds of caterpillars like tomato hornworms, cabbage loopers, corn earworms, cabbage worms, squash vine borers, and European corn borers, among hundreds of others.
9. Parasitic Nematodes
A word of warning – don’t mix up these beneficial parasitic nematodes with root-knot nematodes; the latter can be destructive. Parasitic nematodes kill their insect hosts within a couple of days of ingestion. While they do occur naturally in your soil, there generally won’t be enough of these to control pests effectively. That’s why you’ll need to buy them for use as an organic, non-toxic and safe method of pest control.
You’ll receive your dormant nematodes in a moist medium. When you want to apply them, simply mix them with water and apply them to moist soil in the evening or when it’s not sunny (the temperature of the soil should be at least 60°F.)
Make sure to completely coat the area with the nematodes, and then add some water. Use all of the nematode mixtures within the span of a few hours, since they will not be viable after that time – don’t save it for future use. To store them, place the sealed container in your fridge until it’s time to use them. However, don’t wait to use them for more than 4 months, since their efficacy declines the longer they’re in storage.
Nematodes provide excellent protection against root maggots, weevils, squash vine borers, armyworms, cutworms that are dwelling in the soil, armyworms, and grubs that live in the soil like Japanese beetle larvae.
You can use this responsive pest control method on crops meant for fruits and vegetables. A soil-based bacterium, spinosad kills off garden pests like loopers, spider mites, bagworms, beetles, borers and tent caterpillars. You spray to apply it in liquid form, and after it dries, it will kill off the pests that ingest it.
Spray this in the evening so you don’t harm beneficial insects like bees. This organic pest control product is sold in both dust and liquid forms under multiple brand names, so simply search for spinosad on the active ingredients list.
Pyrethrin is a popular choice of botanical insecticide in the United States. Extracted from chrysanthemum, it is a particularly safe choice as it is not toxic to mammals at all. However, it’s lethal against insects even in low doses.
Once flying insects have been exposed to it, they will drop immediately, even if they haven’t been killed. This rapidity, combined with its safety, is the reason why it is so commonly used. To ensure the death of the insect, some products contain a mixture of pyrethrin with other solutions.
12. Diatomaceous Earth
If you would prefer to not use any chemicals at all, you could try using diatomaceous earth. This food-grade powder is made of fossilized diatoms – a form of algae. The skeletons of these diatoms are extremely hard, so much so that their sharp edges serve to cut up the bodies of pests and kill them off by dehydration within a couple of weeks.
The particles are too small to hurt people or beloved pets. Sprinkle diatomaceous earth in your garden bed when it’s dry – the material is not as effective in wet conditions. It’s most effective against cutworms, Japanese beetles, ticks, flies, slugs and crickets. However, use it with some caution, since it could also kill off beneficial insects.
13. Companion Planting
Companion planting involves planting different plants close to each other in order to maximize space and pollination efforts, increase the productivity of crops, and yes, control pests. This gardening technique allows you to take advantage of the insects inhabiting one crop, which will then feed on the insects dwelling on other crops nearby.
For instance, you can plant leeks and carrots together to protect the carrots. Lettuce and radishes planted together will repel the earth flies that would otherwise attack the radishes. Use daffodils to repel mice, onions to repel rabbits, and castor beans to wade off moles.
You can also use certain minerals to control pests, like sulfur, which will control thrips, psyllids, and spider mites. Sulfur is sold as a liquid, paste, or dust which you combine with water, and can be used on vegetables like peas, beans, tomatoes, and potatoes. It is not toxic to humans, but take care while using it as it could irritate your eyes or skin.
Don’t use sulfur during dry weather when it is hotter than 90°F. Plus, sulfur is not compatible with other pesticides, so you can only use it by itself.
You can use Bordeaux mixture, a combination of lime and copper sulfate, to target and kill certain insects on vegetable crops. Don’t use this all-natural pest control method in wet or cool weather, or you run the risk of damaging the leaves of the plant.
15. Trap Crops
These are plants that are planted for the specific purpose of attracting pests away from the crops you do want. They’re an alternative for insects that would otherwise nibble at harvestable crops. You can plant these trap crops every few rows with other crops, or around the garden’s perimeter. Time the planting so they coincide with when pests will invade. You can simply destroy the crops if they’re infested with pests, but it might not even come to that since the crops will also attract beneficial insects.
Which of these organic pest control methods would suit your garden best?