Your Organic Garden:
Pest Control Without Chemicals
Organic garden pest control might seem like an oxymoron. But according to Nature, it's not. It contains a mixture of preventative methods, as well as supporting the natural eco-systems found within nature. Although there are natural products for controlling insects, intervention by such means should be the last thing done.
The most important thing to remember in regards to controlling pests in the yard and garden: annihilation is not the answer!
A healthy ecosystem, as well as a healthy yard and garden, must have insects. They are a crucial part of the biological system and should not be eradicated. Insects feed birds, lizards and other wildlife, assist in pollination efforts, help break down soil nutrients and compost and become soil nutrients/compost themselves when they die.
They are a vital link and removing them from your garden or yard completely will surely cause more problems than it solves.
Despite the gardener's best intentions, Nature will improvise. - Michael P. Garafalo
Benefits of Organic Garden Pest Control
Plants sprayed with pesticides lack certain nutrients only produced when they are nibbled on by insects. Likewise, pesticides kill beneficial soil microbes, creating an unhealthy environment open to disease without any biological means of protecting itself.
Contact with pesticides has been linked to fertility issues, childhood cancer, Alzeimer's and much more. Even so-called safe usage, which is rarely seen, still puts chemicals into your blood stream, putting you at risk years later.
Also, keep in mind that beneficial insects are slow to reproduce. When an insect attacks, beneficial insects move in to eat. But when a pesticide is sprayed and kills most of them off, it will take many weeks to reestablish themselves. Harmful insects, such as aphids, are much faster to reproduce. They will quickly replenish in numbers before the beneficial insects have time to recover, leaving your plants in worse shape (and a gardener more likely to spray again, perpetuating the cycle).
Prevention Is The Best Medicine
Before insects invade or become a problem, the following organic garden pest control methods should be applied to prevent infestations from occurring.
- Maintain Soil Health: This is the first and foremost step to organic garden pest control. Sick plants are much more susceptible to insect invasion. Keep them watered properly (not too much, not too little), amend the soil with compost and mulch, use only organic fertilizers and plant them in the right place so they are getting proper amounts of sun and shade. Compost tea is also a great way to keep plants happy and it helps to take care of anything funky going on in your soil by introducing healthy bacteria. You may also wish to test your soil for nutrients it could be lacking. An inexpensive test can be purchased at garden centers or you can order a professional test that will give you much more comprehensive results.
- Companion Planting: Companion planting is another important part of your organic garden. Pest control examples of this: garlic is said to drive off aphids from roses; basil is used to protect tomatoes. Things should be planted closely together (high-density) and interspersed with other plants to create a permaculture-like habitat, rather than a monoculture.
- Silver Reflective Mulch: A fairly new tool in the organic garden pest control toolbox but it's pretty cool. It's a thin, silver sheet laid down over the soil and around plants. It works two ways: One is by being shiny and freaking out birds and insects to keep them away. The other is by shining light on the underside of leaves to repel shade-seeking insects. You can read one test gardeners success with silver reflective mulch here.
- Neem Oil: This is an oil from the pressed seed of a Neem tree. It is used worldwide to repel insects, such as ants, aphids, beetles, caterpillars, cockroaches, houseflies, leafminers, mealy bugs, nematodes, snails, termites, and many more, including controlling fungus and mildew. It requires processing and should be purchased commercially for the proper concentrated use in organic garden pest control.
- Garlic Oil Spray: Garlic oil is also used to repel insects. You can make a garlic oil spray by soaking fresh minced garlic in vegetable oil for several weeks. This can be mixed in a spray bottle with about 4 parts water to one part oil and sprayed on your leaves or around the stems of your plants. Alternatively, as described above with companion planting, some insects may also be repelled by planting an abundance of garlic closely together with other plants.
Organic Garden Pest Control
When repelling and prevention don't work, it's time to move onto other organic garden pest control methods. Practiced in the following order, you will save the big guns for last.
- Beneficial Insects: Beneficial insects are a must in organic garden pest control. Lady bugs, praying mantis, some spiders, lacewings, certain types of nematodes and even wasps will take care of many insect problems. Certain flowers will attract these insects: herbs like dill, fennel and cilantro; flowers like cosmos or geraniums or even dandelions are said to attract ladybugs. Or you can get a local community going by purchasing them from a local plant nursery. Just remember if you don't have enough for them to eat they won't hang around, so don't purchase 500 ladybugs before you've seen any aphids. Read more about Read more about beneficial insects here.
- Other Beneficial Creatures: Many amphibians or reptiles, such as lizards or frogs, will happily gobble up your insect problem. Backyard birds will often do the same. It's important to create a safe, healthy habitat for such animals to live. Keep your cats indoors, set up a birdhouse or maintain a small water source (something that can be easily cleaned in case of mosquitoes). You may even consider creating an entire habitat and purchasing frogs naturally found in your area that can set up house in your yard. But be sure you never introduce an animal not normally found in your area!
- Hand-picking: This may be time-consuming but in most healthy gardens it is an efficient, inexpensive (and sometimes, therapeutic!) way of taking care of small insect populations, such as tomato horn worms or aphids. Check the undersides of leaves, and squish bugs you find or remove the leaf entirely. Practicing this organic garden pest control technique for a few minutes each day should prevent most infestations from becoming serious problems.
- Copper and Salt: Used in areas with a slug problem, copper can be purchased in strips to place around plants, or the edges of containers or garden beds. Slugs avoid the shock the copper gives them. Salt will also kill slugs in high enough concentrations, although too much salt in the soil can be unhealthy for plants.
- Sticky Traps: Traps (similar to fly paper) attract insects with color or odor, trapping them on the highly sticky surface. These are great during the first insect hit of the season for removing a large number of bugs. The traps can then be thrown away.
- Soapy or Oily Water: Spraying soapy water or an oil and water mixture suffocates insects, such as aphids. It is safe to use around beneficial insects, but needs reapplying after rain. The sun can also cause burn spots on sprayed leaves, so spray primarily on the undersides.
- Bacillus thuringiensis: Bt is a naturally occurring bacteria found in the stomachs of caterpillars. Incidentally it's used to kill caterpillars, such as the grape leaf skeletonizer or tomato hornworm. It is mixed with water and sprayed on the underside of leaves. I have not had much luck with this but many people swear by it for any type of caterpillar. Again, it can affect beneficial caterpillars, such as butterflies, so it is really a worse case scenario product.
- CedarCide: This completely natural, non-toxic, chemical-free prouct is made from cedar oil, a natural bug repellant. The pleasant smell is safe for plants, animals, and humans and works on a multitude of insects.
- Diatomaceous Earth: According to Wikipedia, DE is "a naturally occurring, soft, chalk-like sedimentary rock that is easily crumbled into a fine white to off-white powder". It's the fossilized remains of diatoms and acts both as a repellent and a bug assassin. It can be sprinkled on or around the plant or mixed in water and sprayed onto the leaves. To the bug it supposedly looks shiny and sparkly to scare them off. If any daring bugs go near it, it sucks the moisture out of them. I've also been told it is razor-sharp to insects and can cut their exoskeletons. DE can harm beneficial insects so it should only be used when absolutely necessary! It can be drying to the skin of humans and should not be inhaled (like any rock sediment, I suppose). Also, it may not work well in very humid climates and will usually need reapplying after rain. Be sure to purchase food grade DE, not the stuff they sell at pool supply stores.
- Integrated Pest Management: Complicated and involved, I couldn't begin to explain this method of organic garden pest control in its entirety. It relies on knowledge of the specific insect and its life cycle, preventative measures, manual and biological controls, and lastly, chemical or organic pesticide intervention. Usually used in large scale farming, it can be applied to organic garden pest control at home by forgoing any chemical pesticide.
Give It Time to Balance Out
Gardening requires lots of water - most of it in the form of perspiration. - Lou Erickson
If you have previously sprayed chemical pesticides, give your garden time to balance itself out. You may see an increase in insect attacks and you may even lose a few plants. Stay on top of it with these organic garden pest control methods; don't sit back and hope Nature sorts it out. You created a imbalance and Nature will appreciate your help in sorting it out. And don't expect a balanced ecosystem overnight or even in a year. Restoring health to an unhealthy environment takes time, work and lots of compost.
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