Integrated Pest Management is an environmentally friendly, common sense approach to controlling pests is a mainstream practice by organic gardeners. It makes a lot of sense from a permaculture viewpoint, though we put a lot more emphasis on soil health as the ultimate remedy.
The goal is not to kill all pests or control them all or the diseases. The goal is to control them enough to give you a decent yield. In a chemical free system, you will have pests and you will have crop loss. The trick is to not have too much loss.
Keeping some pests in your system ensures there is food for predators and a balance will be established.
Remember, If almost all pests are killed by poisons then those that have resistance will provide the genetic basis of the future population.
In our food forests, we have rarely had to deal with pests. The soil is good enough and there is enough diversity that they just don’t get a foothold. This has been true for the most part in our annual gardens, but because we often grow in degraded areas or areas with little food for wildlife, our annual gardens can be like a flashing beacon to hungry insects. We still have fewer problems than many because of our soil, and because we time plantings to avoid heavy pest pressure when we can.
First step - Do Nothing
Often, pests will show up first and rip up some plants, but soon predators will follow and bring them under control. If you control them too much, there is not enough food to attract predators.
Example: We had a significant attack of aphids on our beans the first year of our garden. We watched as they sucked the life out of our plants, and constrained ourselves from doing anything about it. Within a month, those beans were loaded with pest predators of all shapes and sizes. It was like Blade Runner in there! Aphids are a gourmet meal to a lot of different types of predators. Not only were they brought under control, but those predators soon found other pests to munch on as well. This can go against our grain and instincts; we want to save the plant. But having patience and letting nature create a balance will save more plants and create much less work in the long run.
Black bean aphids.
Lady bug at work. One ladybug or one baby ladybug can eat hundreds of aphids. Other aphid predators include a variety of flies, wasps, lacewings, mites and more. They’re a major food source for the ecosystem and all by themselves, they support a diverse and awesome predator network.
Example: We were very concerned about gopher damage on the roots of our baby fruit trees. We studied up on traps and even bought some. We monitored their activity near the trees. By monitoring, we noticed something. They didn’t come into the orchard at all. We figured out that they preferred the wild meadow to the mowed orchard, and the vibration of our frequent visits was another discouragement. We learned some valuable things about their patterns by doing nothing but observing.
Gopher mounds.
Occasionally they show up near our garden. One approach we came up with is to dig into their mound about 2 feet, and then pour some of our pee bucket (wood shavings mixed with pee) into the hole. If there are several holes in a circle (a sign of a female den) we do it to a few or all of them. Or we pour coyote urine pellets into them (only need a few). They really hate that and usually move out with no further intervention. We figure if there’s enough of it, they might think a coyote or human is going to den right there with them and it’s not safe. We’ve thus found a way to co-exist with them.
They aerate soil and provide predators with a constant supply of food that also eat rabbits and rats. As a possible positive side effect, our chickens have free range for years and have never gotten eaten by the foxes, bald eagles, barn owls, hawks, raccoons, bobcats or coyotes that live on or move through our farm. I’ve never had so little predator pressure on chickens anywhere I’ve lived, including in cities, and attribute it to the perpetual abundant supply of familiar food (gophers), perhaps.
Second step - Prevention
We practice minimal intervention pest control. This is a good place to use the permaculture principle “Start Small and Slow”. Try to make the least change for the greatest effect. Often that means doing just a wee bit more than “nothing.” There is an echelon of intervention that starts with ensuring the plant is healthy, moves to biological controls, mechanical controls, and finally, poisons.
Maintain healthy crops
Pests are attracted (by smell) to weak or stressed plants. Yes, weak and stressed plants put out an odor that pests can smell. Nature’s way of taking out the weak, apparently.
The best way to ensure plant safety and health is with healthy soils. The right amount of water is important too, but most plants can experience some drought and still remain healthy. Sunlight is also a factor - a shade loving plant will stay stressed in full sun and vice versa.
Plant appropriate cultivars
Get specific types of plants that do well in your ecosystem. Example: Georgia peaches are very susceptible to fungus in Florida and likely won’t survive. They definitely won’t give reliable crops of peaches every year. Florida peaches do great here, however. We have some freezes, but are also typically hot and humid in Central Florida. We grow both cold tolerant avocados, and heat and humidity tolerant plums, pears and peaches on our farm. We couldn’t grow both temperate and subtropical plants here, without the right cultivars.
Monitor your plants
Catching problems early can save a lot of time and handling later. For instance, tent caterpillars can quickly cover an entire orchard if left unchallenged. This is one pest we’ll hand remove, early on, to prevent spread. They’re easy to spot but you have to be out there looking.
This is a good stage to catch tent caterpillars. They can expand to cover your entire tree if it’s small, and will defoliate it. This usually won’t kill the tree but can slow it down, or stress it, opening it up to other pests. Simply knocking the tent to the ground can handle it.
You can knock this tent into a bowl of soapy water, or spray it with the water (this is the strongest type of “poison” we use - it doesn’t harm predators, or anything, unless sprayed directly on it and breaks down quickly). We have had tent caterpillars on larger trees and done nothing with little harm, but if they show up early in the season on a small tree, I would remove them.
Understand your pests
I’ve never had to spend a lot of time on this, because the other approaches work so well. But if you have a particular persistent type of pest, or it’s aggressively taking over, it’s good to understand it as well as possible.
Observe. Notice the insects around your plants and signs of damage.
Identify the insect or animal responsible for damage. Sometimes you can’t, and then you can defend in other ways. There are some fabulous gardening resources online these days, in social media groups for insect ID or on websites that can help you with these steps.
Understand the life cycle of the pest. Pests have seasons when they are breeding, eating, or dormant. This knowledge can help in a variety of ways. You can plant vulnerable plants when pests are dormant or not eating as much, or you can interrupt the life cycle of pests that spend time in soil by using chickens or other methods. Interrupting or interfering with their life cycle is one way to reduce their numbers. See the “controls” sections below for more info on how to do this.
Biological Controls
These are organic methods that are aimed at balancing the system so that nature herself can protect your plants.
Beneficial fungi and bacteria in healthy soils can kill or repel pests and disease. These things will naturally occur if you don’t till your soil, spray or leave it exposed or severely dried out. But there are many organic fertilizers and treatments, like compost teas, that can boost the health and numbers of these.
Beneficial nematodes will eat root knot nematodes, found in healthy soils. These can be imported in some cases, but if you are creating good soil, they should eventually show up on their own.
Compost teas, or nutrient boosts are the first thing I’ll try if plants are struggling. The idea is to offer the plant complete nutrition so it can fight off whatever is attacking it. Nutrient boosts are ways to jump start or boost soil health which supports the plant in turn. We use manure or compost teas, fungal compost teas, comfrey soak, fish emulsion or fish waste, seaweed concentrate, or a quality organic fertilizer. Minerals, from granite dust or rock or seaweed, can also help clear up a lot of problems with plants. This helps boost beneficial organisms in your soil; it feeds them.
Predator support, like insectary plants, offer food and habitat to pest predators. Plants in the carrot family are especially useful as their small flowers offer nectar to predatory wasps, whose babies eat caterpillars and other pests.
The Ichneumon wasp (there are many types, none have stingers) loves the small flowers of cilantro, dill, fennel, carrot, Sweet Anne’s Lace, etc, for food. They are also found on mustards, many herbs, asters and other flowers. They will show up on their own if you have small flowers in your garden. A stand of native wildflowers can provide great habitat and food for predator insects. We always ensure there are native flowers near our gardens.
Providing habitat, protection, and water for lizards, toads, garden snakes and other predators can also help bring balance. A pile of medium sized rocks can be lizard habitat and also allow water to condense, providing them with moisture. A pile of small logs can provide habitat for many predators like garden snakes or toads (if you have many poisonous animals in your neighborhood, this can hide them as well, use judgment).
Trap plants can attract pests to them. After observing the aphids on our beans, we started planting bean cover crops a month earlier. By the time our food crop was planted, predators had already found the aphids and were controlling them. We’ve also used sunflowers as trap plants since almost all insects like them. We plant them away from the garden, drawing insects there instead of into the rest of the garden.
Sacrifice plants - When I see a weak plant being attacked by insects in the garden, I often don’t remove it. It is keeping pests away from the other plants, while bringing in predators to create balance.
Chickens, ducks and turkeys - There are pros and cons to these birds in your system. Chickens scratch for pests and disturb the soil so I tend to mainly use them to prepare new beds or in mulched perennial gardens. They will rip up an existing veggie garden and continually disturb the soil, reducing the biological health of it.
Ducks and turkeys tend to be great at reducing snail and grasshopper populations, as well as other insects. They will both also eat pretty much any veggies growing in your garden, though they tend to prefer insects (no guarantees though). We have had ducks do very little damage to anything but bugs in our gardens, but others have had them eat greens, berries and other crops.
Duck poo is very messy and ends up everywhere (you will step in it), and they need water that gets dirty fast and needs to be cleaned. The plus is that their poop in water is gold for plants like bananas if you divert it to them. Use an above ground pond with ramps and drain it into a banana circle for a nice energy capture.
Both ducks and turkey can keep grasshopper populations down around the garden, but they can still end up in your garden. We haven’t had a huge problem with grasshoppers even though our farm is a perfect habitat, because wild birds keep them in balance and they have wild food to eat too.
We fence our gardens in, and let our chickens free range in our food forest and use them to prepare new beds by fencing them in around the bed. In the food forest, they generally scratch in the paths or open understory areas and leave perennial plants alone.
We sometimes drop treats for them under trees we’d like them to scratch under - they remove the larvae of pests and can often break the pest cycle for fruit trees. We’ve found that chickens are most helpful for pests because they eat the larvae and break the cycle or at least reduce it.
Weed suppressing crops can save a lot of work for the gardener. This is where timing comes in. Spend the time ensuring you have a solution to ensure garden beds are covered when your growing season approaches so they aren’t taken over by weeds.
One of our favorite weed suppressing crops is cowpea because it covers the beds fast and adds nitrogen to the soil. In temperate climates, vining beans work. Sweet potato is another of our favorites that quickly covers ground.
Wild geranium Geranium carolinianum (smaller, native to FL) or maculatum (larger flower and plant)
Sometimes, the problem is the solution. Wild geranium, a plant I had never seen or dealt with, showed up our system in a pot and quickly started taking over garden beds, then ended up in our new, partially planted food forest, which had a lot of open space, and took over that too. We were weeding it in the garden at first but then I noticed something (applying “Observe and Interact”), which was the plant’s nature.
- It only comes up in winter, when other weeds have died back.
- It covers the beds well and protects the soil from the sun (living mulch).
- It maximally covers in spring, right when other weeds usually start taking over, thus, shading them out.
- It doesn’t have extensive roots and doesn’t use up a lot of nutrition, but the plant spreads out and covers a lot of ground. It’s easy to weed if we do want to remove it from a bed.
- It dies back in spring, just in time for cowpeas or sweet potatoes to be planted, and again, covers the soil with a layer of dead mulch (which also feeds the soil organisms). Can be easily mowed or weed wacked.
- It’s medicinal, has a pretty flower, stays only a few inches high (up to 18"), and is a pollinator.
- It's fairly drought tolerant.
- It stays on improved soils; has not spread into other parts of the farm, thus can be easily controlled.
- It’s perennial and comes back every year on its own in our food forest. We don’t have to do anything whatsoever to have a perfect ground cover with perfect timing.
Geranium Maculatum.
Cover crops feed the soil while suppressing weeds. Cover crops we’ve used are buckwheat, cowpea, velvet bean, iron clay pea, sunn hemp. If weeds do take over, try to chop them down before they seed. You can save yourself a lot of future work by not letting them seed.
Mechanical Controls
Insects
Barriers such as screens or row covers can be useful during peak grasshopper or migrating bird season (for berries) if nothing else is working.
Traps such as sticky tape are nontoxic to plants as well. We’ve personally found that these are not that effective.
Hand picking can work with pests like tomato hornworms, which are large and not very numerous. We’ve reduced out of control army worm populations on specific plants this way. As a note, we did this strategically. We picked only the adults starting to metamorphosize and left the rest. Soon, a small flock of bluebirds showed up, perching on the fence and dive bombing the army worms for days. They were reduced in number enough to let our squash put out lots of fruit. We had left some dead trees standing in our forest, as we know that bluebirds nest in them, and we wanted to ensure we kept them in our system. They are voracious eaters of pests, definitely a friend.
Leaf spot or Cercospora ocimicola is commonly found on basils. Hand pick the leaves with this on them, and bury them, away from the basil. This can flare up in excess humidity, and when it rains or you use sprinklers that cause soil to splash onto the plant (common source for many funguses on vegetables especially). Most fungus doesn’t survive being buried so mulching with new mulch every year can prevent its continuation.
Vacuuming can work with very small, numerous insects like white flies or fungus gnats. We used a hand vacuum on our microgreens after a major white fly infestation.
Fans are an effective way to keep white flies and fungus gnats out of a greenhouse system. This was more effective than the vacuum as it kept them off the plants in the first place. It also kept fungal pressure down on our microgreens.
Wind can damage plants if too strong, but a breeze, even a strong breeze is highly valuable in keeping fungus off leaves or fruit. It’s helpful to keep fruit trees pruned so that wind can reach all parts of it, especially fungus prone fruit like peaches.
Weeds
Picking weeds is always an option and one that will come up regularly if you don’t design to avoid them! Note, it is better to chop them off with a sickle or other tool rather than pulling from the roots if possible, as constant weed pulling disturbs the soil. This reduces fertility.
Suppressing (cardboard, mulch, etc) keeps weeds under control, greatly reduces your workload, protects soil and can even help build it (with mulch). Cardboard does have some toxicity so we recommend you use organic matter whenever possible.
Use dried grass, straw, spoiled hay, wood chips, etc for mulch to hold down weeds, protect soil and feed the soil.
Crop Sanitation (disease)
Keep tools clean. One of the fastest ways to spread disease is to trim a diseased plant and then go and trim all the others. You are contacting an open wound with the disease from the first plant! If working with diseased and healthy plants, best to trim healthy ones first, wash your tool, then trim diseased ones and wash it well again. This is a neglected step that can cause an “outbreak” where otherwise plants would be able to fight the disease off themselves.
Remove diseased plants and leaves and dispose of them outside the system. This isn’t always necessary or desired. Sometimes, you want to leave a weak plant as a trap plant for insects. But if there is an air borne fungus, for instance, like tomato fusarium, it’s easiest to remove the diseased plants (not into your compost pile, unless you know it gets hot enough to kill that fungus).
Killing Pests
We almost never use pesticides or fungicides but when we do, we use them in very focused ways. Again, think of the permaculture principle of making the least change for the greatest effect. The main pest we have that doesn’t have a lot of predators is the stink bug. We have several types. They suck the juice out of fruits, and this can deform or discolor them. It doesn’t affect the flavor nor does it make the fruit inedible but they don’t look good, so are harder to sell.
One year, when we first arrived, they heavily attacked our tomatoes. We did spray them with soapy water (especially the babies) because they would have made the whole crop unusable to share with others. Since then, we’ve created enough abundance that they haven’t too heavily infested any one crop. We expect that further balance will be achieved as more of our fruit trees start producing.
Soapy water. Our top method of killing pests on crops we just don’t want to lose is to spray soapy water directly on pests, or knock insects into a bowl of it. It kills insects rapidly. We use organic soap; it doesn’t need to be stronger than that. The film suffocates them within seconds.
Neem oil directly on fungus. We have occasionally used neem oil on fungus that seemed to be getting out of control, mainly on the trunks of trees. This can also be used for scale insects though we’ve found it’s easier to just knock them off of the tree if we catch them early.
Don’t ever, ever use pesticides, even organic ones, on the entire system – it can throw the balance out tremendously. You’re killing predators as well as pests. It will take the predators a lot longer to recover than the pests so you just gave yourself more work.
We believe that a balanced, perennial system with healthy soil will resist pests and diseases in almost all cases.
Summary
There are times when what you do won’t be sufficient. We tend to let plants go that aren’t surviving with a balanced, natural approach. It usually takes a perennial system years to establish a balance between pests and predators. We are patient and let nature sort it out and find its balance, ensuring that we’ve done our part by providing a nutrient rich, diverse and balanced environment for our plants.
Handling pests is a great opportunity to work with nature rather than against her. Consider pests to be a part of any healthy ecosystem. Understand their function and how nature keeps a balance, and design that into your system. Look for the benefits they bring as well as the downsides. For instance, fire ants aerate soil. We’ve learned a lot about nature and our plants by observing pests and their relationships to the system. It’s been an important part of our fascinating journey.