By Mary 'Klibs' Dralle, for Let’s Talk Plants! August 2024.
Natural Insect Pest Control
It is that time of the year when pest insect pressure can be very high as they are breeding and multiplying in the summer heat. There is a three part holistic non pesticide system using nature to control insects in your garden. Many of us have been utilizing it all around the world for a long time. Much has been written about these tried and true ways. Here are the steps to point you in the right directions.
STEP ONE: Employee plants that are known to keep certain insects under control. This is another form of companion planting where plants help each other out. Plant any combination in and around your garden to help keep the bugs away.
Basil, while it is a marvelous culinary herb, like Genovese Basil, Sweet Basil, Osmin Purple Basil, Lemon Basil or Thai Sweet Basil, it deters mosquitoes, flea beetles, and cabbage webworms from tomatoes, peppers and eggplant, to name a few. Have multiple plants of different varieties in your garden. You can never plant too much as it can be used as a delicious iced tea, sauces such as pesto, and dried for future use or given as gifts to friends and family members.
Catnip while you might attract every cat in the neighborhood into your garden to deter rodents, it keeps mosquitoes, flies, roaches, and ticks away. As a member of the mint family, it emits nepetalactone that causes pain in the TRPA1 receptor insects. Way back in the olden days of England, catnip was a tea meant for human consumption. And it reacts with your system in a similar ways as your cat but a bit milder. The same chemical, nepetalactone, binds to a different set of receptors to creates euphoria!
Chives, garlic, or any other alliums around tomatoes, lettuce, strawberries, and peppers, repel aphids, cabbage worms, slugs, and carrot flies. Plant them at Halloween and harvest them on the Fourth of July. Reserve some of the harvest to make a garden spray mentioned later in this article.
Dalmatian Chrysanthemums aka mums dissuade flies, moths, fleas, ants, aphids, cutworms and other larvae, and thrips from the garden in general. They contain Pyrethrin, a neurotoxin, which kills insects, and is safe for animals. Grind up the dried flowers and sprinkle around garden.
Lavender, in every garden, next to every garden gate, plant it on the left for luck and love and to repel mosquitoes, moths, and flies. It comes in many varieties that have multiple uses. Culinary lavender such as Hidcote, Munstead and English lavender are quite delicious. Also, Lavandins, hybrids of English lavender, like Grosso and Provence, are very tasty, too.
Lemon Grass (from which Citronella is extracted) repels mosquitoes and tastes great in many Asian dishes.
Marigolds, with their sunny look in the garden keep knot root nematodes (nematodes that are not beneficial), tomato hornworms, cabbage worms, thrips, squash bugs, whiteflies away. Like mums, they can be planted in and around the garden.
Petunias that are blue, multicolor, orange, pink, purple, red, white, yellow, and even black in color and can be planted anywhere the basil goes. They add a splash of color while keeping aphids, beetles, tomato worms, and squash bugs.
Side note: they have a tendency to attract slugs/snails with their licorice fragrance so make sure the chives and/or garlic are close by.
Rosemary, just like lavender, goes next to every garden gate on the right so you remember and it repels mosquitoes as well as cabbage moths and carrot flies. A branch makes a tasty skewer for lamb, chicken or beef!
STEP TWO: Manage pesky vegetable eating bugs in the garden by attracting carnivorous birds and/or insects to patrol and monitor your garden.
Here is a list of beneficial garden helpers:
Beneficial Animal, Category, How They Help in the Garden (their particularity)
Blue Birds, Bird, grasshoppers, crickets, beetles, larvae, and moths. (Cavity Nester that can be enticed to live in a bird box.)
Chickadees, Bird, aphids, whitefly, scale, caterpillars, ants, and earwigs. (Cavity Nester, too.)
Grosbeaks, Bird, larvae, caterpillars, and beetles. (Open Cup Nester that need sturdy branches to hold their nests.)
Hummingbird, Bird, ants, aphids, fruit flies, gnats, weevils, beetles, mites and mosquitoes. (Compact Cup Nesters that must have spider webbing to hold nest together.)
Nuthatches, Bird, borers, caterpillars, ants and earwigs. (Cavity Nester, too.)
Oriole, Bird, larvae, beetles, and grasshoppers. (Open Cup Nester.)
Sparrows, Bird, beetles, caterpillars, and cutworms. (Open Cup Nester and will take advantage of a box if it is available.)
Swallows, Bird, moths, beetles, and grasshoppers. (Cavity Nester, too.)
Titmice, Bird, aphids, leafhoppers, caterpillars, and beetles. (Cavity Nester, too.)
Warblers, Bird, caterpillars, aphids, and whitefly. (Open Cup Nester and will take advantage of a box if it is available.)
Woodpeckers, Bird, Larvae, beetles, weevils, and borers. (Cavity Nester, too.)
Decollate Snail, Mollusca, these are carnivorous snails that eat the common garden Helix snail. Once the garden is cleared out, they eat decomposing organic material and love compost bins!
Dragonflies, Insect, mosquitoes - they can eat up to 1000 per day. They like to hunt from a perch, so place guywires over your garden.
Lady Bugs, Insect, aphids, small spiders, mealy bugs, and other insects and mites they can attack and subdue.
Braconid wasp, Insect, lay their eggs on tomato hornworms and other caterpillars.
Hoverflies, Insect, as vital pollinators, the adults feed on pollen and nectar while their larvae eat aphids, caterpillars, beetles, and thrips.
Soldier Beetles, Insect, adults eat aphids, mealy bugs or other soft-bodied insects and on pollen or nectar. Their larvae feed on eggs and larvae of small insects, worms, slugs and snails, butterflies and moths.
Tachinid fly, Insect, lay their eggs on corn borers, gypsy moth caterpillars, grasshoppers, Japanese beetles, Mexican bean beetles, squash bugs, and green stinkbugs.
Trichogramma wasp, Insect, lay their eggs inside the eggs of over 200 different insect pests, preventing the pests’ eggs from ever hatching. They are used by many growers in San Diego county to control Asian citrus psyllid and greenhouse thrips.
And let's remember the Garden Spider…
Photos courtesy of Catherine Werth, local birder and photographer, Ramona, CA.
The way is to attract carnivore eating birds and insects using specific plants and/or shelter either in, or, around the garden. A hedgerow, a line of closely spaced (3 feet or less) plants that are trained to form a barrier or to mark the boundary of a garden area, is an excellent tool. When designing it, remember to include plants that will attract beneficials, shelter for their needs and a good source of flowing water. Plants to consider for the hedgerow could be California Natives such as blue elderberry, Sambucus mexicana, laurel sumac, Malosma laurina, toyon, Heteromeles arbutifolia, holly leaf cherry, Prunus ilicifolia, California coffeeberry, Fragula californica, coast barberry, Berberis piñata, and holly leaf redberry, Rhamnus ilicifolia.
Within the hedgerow, shelter can be constructed for some birds like cavity birds.
Guidelines for bird boxes:
Use aged red cedar if possible.
Wood should be around 5/8" thick for insulation.
Rough wood makes it easier for chicks to enter and exit.
The floor-space should be 5" x 5".
The depth should be 8".
The entrance should stand 6" from the floor.
It should stand 5' - 10' from the ground.
While this may not be considered organic, ...
"Above all else, at the start of spring, on or around, February 1, spray the inside with WD40. It will not harm the birds in any way but will deter bees from setting up a hive," -Dave Bitner, Wildlife Research Institute, Ramona, CA.
For specifics on birdhouse plans can be found at Birdhouse Plans for 70 North American Bird Species.
To provide shelter for bugs consider building a bug hotel. It can be made from leftover materials. Some choose to make a house-like structure with shelves and dividers and others use board and bricks to create a large more diverse design. The items used for stuffing can be anything from hollowed out bamboo to old paper egg cartons to logs with holes drilled into them to pinecones. Some choose to put a bit of wire over certain chambers to hold material in place as shown in this one from www.craftionary.net.
Meanwhile, Lee Bunkhill, the Garden Ninja, likes to build his on the large and free form scale as he says the smaller ones do not provide enough diversity. His version, 'How to build a bug hotel: the right way!, can be found on YouTube. Also, he prefers to create houses for the solitary bee in wooden fence posts rather than the hotel as it gives them a bit more privacy.
A solar powered water fountain can provide water for insects to drink and birds to frolic in. This one was made using a repurposed plastic bucket and solar pump. Rocks and marbles have been added for insects to stand on. Also, a saucer can be used as well and may need to be filled often.
STEP THREE: Lastly, if a spray has to be used, Glycerin Soap, as called out in Korean Natural Farming practice, is a good alternative. Cho Han Kyu developed the Korean natural farming method. In 1965, he went to Japan for three years as an agriculture research student and studied the natural farming methods of the three teachers: Miyozo Yamagishi, Miyozo Yamagishi, and Kinshi Shibata.
Upon his return to Korea, Cho combined his newly acquired knowledge with traditional Korean farming and fermentation methods (e.g., as used in Korean foods such as kimchi) and gradually developed what is now called Korean Natural Farming. He put it into practice by setting up a "Labour-Saving Abundant Harvesting Study Group" in 1966. He opened the Natural Farming Life School and Research Farm in Goesan County, North Chungcheong Province, in 1995.
Today, it is a worldwide method used by many Permaculture designers. High quality glycerin soap is made from vegetable oil and potassium hydroxide and will break down in the garden without leaving harmful residue that will cause more problems later on down the road. JADAM Wetting Agent, aka Glycerin Soap, can be made using this link, DIY JADAM Wetting Agent(JWA) 20L for Gardeners. Natural liquid soap. Homemade pesticide. Once you have the soap, either homemade or purchased, it is time to make the Garlic Garden Spray.
Ingredients:
1 gallon of good, filtered water
1 head of garlic, either reserved from harvest as mentioned earlier or purchased, rough cut into chunks
1 to 2 tablespoons of crushed hot pepper flakes
1 to 2 tablespoons of glycerin soap, homemade or purchased
To make the spray:
In a large stock pot over high heat, add water, garlic and pepper flakes.
Bring to a rolling boil.
Remove from heat and allow it to cool naturally overnight.
Strain solids and store in a gallon jug. (Perhaps the one from the water).
Add soap, label as 'Garlic Garden Spray Do Not Drink' and store in the refrigerator.
To use:
Pour into a spray bottle.
Spray the underside of the leaves on the affected plant. Remove and discard any eaten leaves outside of the garden. If a fire pit is available, burn them.
Side Note: While it is good to spray on your plants in the early morning hours, avoid spraying it directly on the soil as it can kill earthworms.
Until next time, keep those hands soiled.
