Praying Mantis Guards Tomato. Photo by VladUK.
When holes or spots start appearing on plant leaves, a lot of gardeners’ knee-jerk reaction is to reach for a chemical spray, and set out to eradicate the pests. But this “solution” doesn’t really address the systemic issues that led to infestation in the first place. Natural methods of pest control are not only better for the environment, but they are more viable in the long run. An unhealthy garden will continue to be plagued by problems and require more and more chemical help, while a well-designed and healthy garden will keep pests and diseases at bay the natural way, with little need for help from you.
Just look at Angelo Eliades’ experiment: he took clones from his thriving forest farm and started growing them in a separate, state-of-the-art hydroponics systems. You might expect the hydroponics plants to do better—after all, they were given the precisely optimal amounts of water and nutrients at all time, and they don’t have all the root competition that plants have in the jam-packed forest farm ecosystem. And the hydroponically-grown plants did do well—for a while. But then a drought started to stress the plants, at which point mites swooped in to finish them off. Meanwhile the equivalent plants in the forest farm continued to flourish with no signs of infestation.
The hydroponics garden, like many modern gardens and farms, was highly vulnerable to pest and disease infestation because it offered high concentrations of one species in the same spot, with no predatory insects around to guard it. This looks like an all-you-can-eat buffet to pests, particularly once the plants started to show signs of stress. The forest garden displayed a much greater pest and disease resistance because it took advantage of the same pest-control strategies that we see happening in nature.
You can bring the same pest-fighting power to your yard or garden following a few simple design guidelines:
Delphinium is a gorgeous border plant that is also potent at fighting Japanese Beetles!
1. Choose native plants and give them the conditions that they are already adapted for. When plants are happy in their spot, their natural pest and disease resistance will be high.
2. Create very diverse plantings. Having a mixture of different plants in an area helps to confuse pests and throw them off of the trail.
3. Develop a healthy soil rich in organic material. The “good” micro-organisms in the soil are vital to controlling the “bad” micro-organisms in the soil.
4. Use plants to trap pests. For example, Geranium is a popular trap plant that has been reported to trap Leafhoppers and Japanese Beetles, keeping your vulnerable plants like Roses and Grapes safe.
5. Use plants along borders to repel pests. For example, it has been reported that Dill repels aphids, spider mites, and squash bugs, Sage deters cabbage flies, carrot flies, black flea beetle, and cabbage looper, and Lavender repels mosquitoes and gnats.
6. Use plants as a natural insecticide. Delphinium is said to poison Japanese beetles that eat it, while the natural pyrethin In Chrysanthemum cinerariaefolium or Painted Daisies can be used to kill a broad spectrum of pests (but this natural toxin should be more of a last resort, as it can also harm humans, pets, and honeybees!).
7. Use plants as habitat for beneficial predatory insects. If you provide the Praying Mantises, Hover-flies, Lacewings, and Ladybugs the conditions they like, they will reward you by sticking around more to snack on your pests.
Following these tips is generally enough to prevent any serious infestations, but if you are still seeing signs of pest damage, there are several all-natural formulas that you can use to protect your plants:
Wayside sells targeted formulas to control for Slugs, Deer, Snakes, Groundhogs, Rabbits, and insects of all kinds. These formulations are so potent because they include the specific scents that are most repulsive and panic-inducing to the target pest species.
Natural Insect Control Spray from Wayside.
Products with Neem Oil are especially handy and versatile, as they smother both eggs and adult insects of most pest species AND they naturally protect foliage from fungus. Apply Neem Oil as protection before pests and fungus get established, and it will be much easier than fighting them once they have a foothold. If you are already seeing signs of fungus, you can fight it with a daily spray of Baking Soda, Soap, and Water. Baking soda is great for treating Powdery Mildew, while water and milk (yes, milk) is oddly effective against blackspot.
To protect your trees from being scaled by pests, add 1 diced garlic bulb, 1 diced onion, 1 tablespoon of Cayenne pepper, and 2 tablespoons of biodegradable soap to a Quart of water, strain the mixture, then add the liquid to wood ashes and make a paste. Apply this in a ring around your trees’ trunks. The pest-repellent liquid in this recipe also works squirted on plants. Citrus Oil is another good ingredient to add to the mix for repelling pests like ants.
To kill on the spot any insects that you see, simply squirt them with soapy water, and the soap will strip the oil from their exoskeleton, drying them out and killing them. Good biodegradable options are Murphy’s Oil Soap or Castile Soap. Use this option sparingly, however, because the soap can also kill beneficial insects. A line of Diatomaceous Earth will deter climbing insects, slugs, and snails because the jagged granules make tiny tears in their skin that can ultimately kill them.
There is a wealth of pest-fighting recipes online, but some are more effective than others. And if you grow a naturally pest-resistant garden to begin with, you should rarely need the recipes!