Natural Pest Control 101

[HOMEGROWN.org]

Controlling pests is a feat in itself, but to do so by natural means is downright difficult.  Defending your garden from an army of pests is dependent on geographic location, crop varieties, climate, and requires lots of time, patience, and trial and error. This HOMEGROWN101 will serve to guide growers on natural pest control methods that can help save your garden from pest distress.

 

(Photo by Mother Earth News)

 

There is nothing worse than seeing well-tended plants fall victim to pesky garden pests.  Be it bugs, blight, or backyard critters, farms and gardens provide a veritable feast for a variety of pests that can inflict serious harm on plants.  Some modern American growers rely on chemical-intensive measures to defeat these pests and protect their plants.  Armed with herbicides, pesticides, and rodenticides, these growers aim to kill the pests and squash their problems; however, the use of these sprays may take care of more than just pests.  A chemical defensive may eradicate the pests that are attacking your roses, but they can also kill beneficial organisms that are helpful for your garden, and health problems in pets and people exposed to these toxics! 

 

And what’s more, pesticides, herbicides and the like are petroleum-based, requiring a lot of resources in order to produce and use them effectively.  These chemicals are not single-use, either.  They must be reapplied in order to combat the evolution of the pests to the chemical onslaught.  It has been noted that there are several pests in the U.S. that have become “superpests,” which have the ability to withstand a chemical dousing and continue to afflict gardens and farms.  Which is why many growers - even large scale! - are turning to natural methods of pest control to keep their plants healthy. 

 

So, how to start controlling pets and protecting plants with safe, natural alternatives to chemicals?  What’s the best way to work with nature in order to combat pests?  Start with the knowledge and know-how of your fellow HOMEGROWNers and figure out which method works for you!

 

It's vital to remember a few general garden-care guidelines to discourage pests from making a home in your rows, start with a healthy garden.  Cut weak or infected plants and dispose of them away form the garden.  Incorporate organic compost, mulch, and natural fertilizers like seaweed and animal manure, which have trace elements like zinc, calcium, sulfur, barium, and magnesium, important for plant development and a repellent for some insects, into your soil.  Clear leaf litter and weeds from your garden in order to eliminate pest habitat and spread clean mulch.  Interplant with companion plants, androtate crops each year to avoid plant-specific infestations. Encourage beneficial insects to keep pest populations low. Water early in the morning to avoid fungal and insect damage.  

 

While pests vary from garden to garden, here is a comprehensive list of common garden pests from Mother Earth News to keep your eyes open for, and the best tactics to combat these pests, discussed in full below:

 

Aphid: Insecticidal soap, attracting beneficials, horticultural oil

Armyworm: Bt (Bacillus thuringiens), handpicking, row covers

Asparagus beetle: Poultry predation, neem, handpicking

Blister beetle: Poultry predation, neem, handpicking

Cabbage root maggot: Crop rotation, beneficial nematodes, diatomaceous earth

Cabbageworm: Bt, handpicking, row covers

Carrot rust fly: Crop rotation, beneficial nematodes, diatomaceous earth

Colorado potato beetle: Poultry predation, neem, handpicking

Corn earworm: Bt, horticultural oil, beneficial nematodes

Cucumber beetle: Poultry predation, neem, handpicking

Flea beetle: Insecticidal soap, garlic-pepper spray, row covers

Harlequin bug: Handpicking, good garden sanitation, neem

Japanese beetle: Handpicking, row covers, milky spore disease

Mexican bean beetle: Poultry predation, neem, handpicking

Onion root maggot: Crop rotation, beneficial nematodes, diatomaceous earth

Slugs: Handpicking, iron phosphate slug bait, diatomaceous earth

Snails: Handpicking, iron phosphate slug bait, diatomaceous earth

Squash bug: Handpicking, good garden sanitation, neem

Squash vine borer: Growing resistant varieties, crop rotation, beneficial nematodes

Stink bug: Handpicking, good garden sanitation, neem

Tarnished plant bug: Handpicking, good garden sanitation, neem

Tomato hornworm: Bt, handpicking, row covers

Whitefly: Insecticidal soap, attracting beneficials, horticultural oil

Cutworm: Rigid collars, Bt, diatomaceous earth

Rodents

Deer

 

More Resources on Common Pests:

Golden Harvest Organics Comprehensive Pest Guide

Earth Easy's Natural Pest Control

Mother Earth News's Organic Pest Control: What Works, What Doesn't?

Pest Management: ATTRA

Rodael: Natural Pest Control

 

HOMEGROWN.org Resources:

Garden Pest Problems

Black Beetles in the Garden

Potato and Raspberry Help

 

A How-To for Controlling Pest Populations and Problems

 

(Photo by Humble Seed)

 

COMPANION PLANTING

Many growers are familiar with the Native American method of planting the “Three Sisters” – squash, corn, and beans – together in organized rows in order to provide habitat for beneficial insects and to avoid pest problems.  Monocropping, planting one crop or separating your crops by type, has the opposite effect on your crops.  It creates a habitat for specific pests, which increases the dependence on pesticides and herbicides, rather than an interconnected, positive feedback loop system.  Mix up monocropping systems by interplanting herbs and flowers between your vegetables and fruits.

 

Companion planting also incorporates plants with strong odors or tastes that are offensive to pests.  By planting them in your garden, it may force pests to find a new feeding ground.  While finding the right companion combination depends largely on what you’re growing and where you’re growing it, some common herbs, flowers, and vegetables include: sweet basil, mints, rue, clove, marigold, nasturtium, onion, radish, and garlic.

 

Check out this article from Seeds of Change and accompanying chart of companion plantings from J.I. Rodale’s Encyclopedia of Organic Gardening

 

HOMEGROWN.org Resources:

Companion Planting Using Herbs

Bonnaroo Gardening Workshop

 

 

ENCOURAGE BENEFICIALS

A healthy, fruitful garden relies upon a strong, interconnected ecological system in which insects, birds, sun, water, and the plants work towards a harmonic biological balance.  Beneficial predator insects take care of pests, who provide sustenance for the birds.  Small mammals manage leaf litter and ground cover, while larger mammals manage the smaller mammals populations.  In this system, there are no needed inputs to create ecological harmony. But, when unwanted pests and pathogens appear, many growers reach for chemicals to protect their plants, putting themselves and their food at risk of contamination, and killing beneficial organisms to boot!  Many common garden insects are important lines of defense in eliminating unwanted pests from harming plants, but fall victim to the chemical onslaught of the ‘cides.

 

(Photo By: Tomato Casual)

 

Here are a few types of beneficials to encourage and ways to do so.  While they won’t eradicate pests, they will restore the ecological balance that will keep problem insects at bay:

 

Birds and Poultry – Wrens, chickadees, and robins eat beetles (asparagus, Japanese, blister, potato, Mexican bean, cucumber, Japanese), cutworms, grasshoppers, and other insects.  Birds will be attracted to birdhouses and nesting shelves near the garden.  Birdfeeders will attract squirrels, so be sure to keep those at a distance far enough away from your garden in order to avoid squirrel problems.

Toads – Toads eat a diet full of slugs and bugs.  Build toad houses in your garden for these amphibians.

Spiders and predaceous ground beetles – Leaf litter and mulch covering on garden floor will provide them with hiding places, but this organic matter does provide food for pests.  Test out how it works in your garden.

Ladybugs/lacewings – These beetles prey on aphids, scales, and more.  They are attracted to wheast or formula 57 in the garden.

Hoverflies – These flies like habitats wildflowers, dill, fennel, coriander, and Queen Anne’s lace and will take care of aphids

Parasitoid wasps – Ground cover like sweet clover, alyssum, yarrow attracts these wasps, who lay their eggs in pest hosts, like cabbageworms, tomato hornworms

Praying Mantis – These large insects eat most garden insect pests.

Garter Snakes – Garters are great for the garden.  They tend to den in tall grasses, bushes, and piles of wood or rocks near the garden.  They keep populations of crickets, grasshoppers, and other insects down.

 

Some beneficials are available for purchase and can be introduced into the garden:

Bacillus popilliae (milky spore bacteria) is great for controlling grubs and will remain in the garden for 10-15 years.  Strains of Bacillus thuringiensis (Bt) is good for controlling caterpillars, Japanese beetle, corn earworm, tomato hornworm, mosquitoes, cabbageworm, potato bugs and elm leaf beetles

Beneficial nematodes – These beneficials enter a host’s body and emit bacteria that liquefies their insides and devours them.  Beneficial nematodes can be applied through spraying, mixing with mulch, and adding to soil to combat mosquitoes, black flies, grubs, carrot rust fly, termites, yellow jackets, grasshoppers, cabbage and onion root maggots, squash vine borer, crickets and caterpillars

 

Resources:

Resource Guide for Organic Insect and Disease Management

Beneficial Insects 101

 

 

NATURAL PEST REPELLENTS AND PROTECTANTS

Handpicking

Flypaper

Traps

Pheromones – These natural scents attract insects into sticky traps; useful for lining your perimeter. 

Floating Row Covers – Lightweight opaque material draped over beds and anchored to the ground allows sunlight and water in, but keeps pests out.  The material is supple enough to grow with the plant and is spun to prevent tearing

Cloche – These miniature greenhouses provide a great barrier for seedlings against pests.  They must be kept open in the heat and for watering

Barrier Paper – scraps of waxed cardboard that are placed at the base of the plant over the stems/roots can protect some plants from pests

Eggshell Barriers

Fences

Pest Potions – Comprised of everyday household ingredients, these homemade repellents can help to deter pests from your plants.  Check out this video demonstration and recipes

 

Resources:

Earth Easy's Traps and Barriers

Use Pest Barriers in Your Garden

 

HOMEGROWN.org Resources:

What's The Best Fence?

Keeping Mosquitos Out of a Rain Barrel

 

 

CONTROL PESTS WITH BROAD-SPECTRUM/ORGANIC PESTICIDES

Pyrethrins – derived from the dried, powdered heads of chrysanthemums flowers.  Very effective in natural pest control – quickly target infestations and kills everything (even beneficials) – use sparingly and spot treat

Diatomaceous earth – kills pests by inflicting lacerations on their bodies – pests dries out and dies.  Powder form that can be used anywhere on anything – useful as a barrier around house or garden, around or on plants. Fossilized remains of diatoms

Boric acid – made from borate commonly known as Borax, is a desiccant and slow-acting stomach poison.  When it sticks or is ingested it takes time – pest can infect the colony

Insecticidal soaps – vegetable-based, non-toxic, kill pests by breaking down waxy cuticles and dissolving cell membranes – cell contents leak out and pest desiccates and dies.  Best on soft-bodied pests (aphids, scales, catepillars, flies, grasshoppers)

Horticultural oils – oils plug the spiracles, holes for respiration, of pests.  Be sure to choose a vegetable-based oil to spray.  Choose between adormant oil, heavier, sprayed when leaves have dropped, and summer oil which is safe on foliage

Neem oil – derived from the seeds/fruits of the neem tree works to kill pests like an insecticidal soap and horticulture oil, but also as an insect growth regulator and antifeedant on aphids, catepillars, grubs, beetles, and mites

 

Resources:

Simple Pest Control

 

 

NON-INSECT PEST CONTROL 

Deer and rodents can do as much, if different, damage to your garden as insects can.  Deer and rodents are notorious for stripping plantings and ravaging grasses.  There are a number of natural, homemade pest control measures that you can take to protect your plants:

 

(Photo By: Tomato Causal)

 

Deer can be controlled by hanging satchels of human hair in the branches of trees, bushes, or around the garden.  They are also repelled by bars of fragrant soap hanging from branches, and hot sauce.  Mix up a concoction of egg, water, liquid dish detergent, and hot sauce and spray it on the plants that the deer are feasting on.  Here are some good recipes to try. 

Rodents are usually searching for open food sources.  Be sure to seal your compost bins and trash bins to deter scavenging rodents.  Rodents (and rabbits) are allergic to peppermint; soaking cotton balls or rags in peppermint oil may do the trick.  Oil must be reapplied after each rain. 

Squirrels get their own category for being one of the peskiest pests. HOMEGROWN tips on squirrel control with videos and links.

 

 

Other HOMEGROWN.org Resources:

Integrated Pest Management and Permaculture

[Carol J. Alexander]

After spending hours each day handpicking squash bugs, I read to use a shop vac to suck them up. The shop vac did not work because the hose is too big around. So we took the bagless Hoover out to the garden and used its narrower hose. Worked great. Saved a lot of zucchini, too. Try it on other pests and let me know your results.

[Hayden James]

I didnt see it anywhere, and perhaps I missed, but I found great success from slugs/snails was with the use of beer.. I pour a little bit in an old tuna can or cat food can(or something of the like--you get the idea, eh?!?). I bury this mostly in the ground so the opening on top is flush with the earth. I add about 1" or so of beer, and the pests love it so much. They drink it up, and fall in :-)... good luck! 

[Louise Hodges]

Pyrethrins are NOT even remotely organic! They are synthetic chemicals and as stated above, non selective.  They are a known causal agent in Colony Collapse Disorder which is wiping out honey bees.

Greenbug carries a line of all natural pest control products that are completely safe yet effective without exception.  You can use Greenbug for Outdoors seconds before harvesting vegetables with no worries.  Greenbug for People is an excellent personal repellent to eliminate mosquitoes, ticks, fleas, etc.

I always carry Greenbug for People and use it to prevent bed bugs as well as for mosquitoes, ticks, fleas, etc. It is all natural, totally safe and it WORKS! Before travel, I spray Greenbug for People on my luggage to make sure no bed bugs latch on in-flight. At the hotel, I thoroughly inspect and lightly spray each linen layer to create a bed bug barrier. Spray my luggage prior to travel back and no worries! I did get bed bugs on a business trip last year and discovered Greenbug then.  Love it! I get it online - just google "Greenbug for People" and it will pop up.

[Hayden James]

THANKS! GREAT to know!

 

 

 

Louise Hodges said:

Pyrethrins are NOT even remotely organic! They are synthetic chemicals and as stated above, non selective.  They are a known causal agent in Colony Collapse Disorder which is wiping out honey bees.

Greenbug carries a line of all natural pest control products that are completely safe yet effective without exception.  You can use Greenbug for Outdoors seconds before harvesting vegetables with no worries.  Greenbug for People is an excellent personal repellent to eliminate mosquitoes, ticks, fleas, etc.

I always carry Greenbug for People and use it to prevent bed bugs as well as for mosquitoes, ticks, fleas, etc. It is all natural, totally safe and it WORKS! Before travel, I spray Greenbug for People on my luggage to make sure no bed bugs latch on in-flight. At the hotel, I thoroughly inspect and lightly spray each linen layer to create a bed bug barrier. Spray my luggage prior to travel back and no worries! I did get bed bugs on a business trip last year and discovered Greenbug then.  Love it! I get it online - just google "Greenbug for People" and it will pop up.

[Caroline Malcolm]

Hi Louise,

 

Thanks for the information.  I don't know much about pyrethrins except that they have been approved for use by the USDA for the National Organic Program, which does not necessarily mean that they are good to use on our crops, especially since they do kill beneficials.  I did not know their connection to Colony Collapse in honey bees, but that is very interesting to note.  

 

I did find an interesting article about the potential hazards of the organic pesticide pyrethrum.  It offers information about the effects of pyrethrum, especially to aquatic life through runoff, and other insects.  It also gives good tips for battling aphids (water hose or garlic spray), whiteflies (sticky traps or the vacuum! Just like Carol mentioned), and handpicking, row covers, Bt, companion planting and soapy water for potato beetles, flea beetles, and cabbage worms.

 

It will be useful to add an addendum to this HOMEGROWN101, I think! Thanks for the tip! 

[Michelle Haugdahl]

I have found that both men and boys seem to enjoy "marking" their territory outdoors when its available. I live in a rural area and have encouraged them to do so around the garden and decorative plants. This seems to help keep the deer, rabbits and groundhogs away from my plants. I have also been told that "marking" a beaver damn will cause the residents to relocate.