Challenging Permaculture Dogma: Fruit Tree Guilds, Hype vs. Reality
Guilds on guilds on guilds on.... guilds?
In the last article, I had talked about my grandfather’s talent for pitted fruits, but I didn’t mention the peach tree that stood dead center of the garden. I didn’t think much of it when I was younger, but as I began to get a bit older and understood more about gardening, it seemed more and more strange for a cool climate. Why would you want to reduce sunlight? I later realized that he used the peach tree to extend the season for lettuce, and around the trunk of the tree, he planted some flowers. What’s worth keeping in mind, of course, is the fact that peach trees have fairly thin canopies, and they were having more of a cooling impact than a shading impact. The idea of planting below trees might seem counter-intuitive, but there are some benefits to the practice. That said, it’s worth detangling fact from fiction.
Recently, we had discussed the management of fruit trees and some fundamentals around fruit tree crops and their unique needs. We discussed how we can use our knowledge of how forests work to be effective managers of fruit trees, and in this episode we’re going to do the same, but along the lines of creating comprehensive ground management, often called orchard floor management, unless you are familiar with permaculture, in which case it’s often called fruit tree guild management, for your fruit trees that both benefits them, the soil, and you. In theory.
If you think back to our episode on soil, there are a few key functions soil plays in providing successful habitats for plant roots— aeration for oxygen, moisture retention for water intake, and nutrients and nutrient accessibility through nematodes, bacteria, and fungi. We talked a bit about how no-till is a better method to maintain the soil structure and biological community, which allows easy transfer of nutrients, water, and oxygen to the roots of plants. We further discussed the role of ground cover to protect the soil from temperature extremes, reducing soil microorganism biodiversity loss, and the role ground cover can play in building biomass. We can use this knowledge and apply it in a practical sense not just for ecosystem restoration, but for ethical food production.
To do this, we need to understand how to A) properly plant your fruit trees, whether they are a rootstock with a scion grafted to it or if they’re a tree purchased from a big box store with a soil & root ball, and B) how to create meaningful plant communities. These plant communities, in certain regenerative and permaculture circles, are often called guilds, whose goal is to create sustainable communities that reduce the need for pesticides and fertilizers. I’ve been hesitant to talk about guilds in describing this episode, and for good reason. Here’s a definition of fruit tree guilds I pulled from a permaculture website, and we’ll use this as our basis of understanding. “The goal of the guild is to underplant a central element, such as a fruit or nut tree, with plants that are highly useful, multifunctional, and that might naturally be found growing together. For example, under-plantings in a guild might include plants that fertilize, repel pests, attract beneficial insects, create mulch, and suppress grass, and more.”
This is a common practice that is most often advocated by permaculture instructors, and for good reason— it sounds very, very good in theory, right? Who wouldn’t love to plant a fruit tree, cover its understory with other edible crops, which all miraculously also reduce the work needed to maintain the fruit tree? You’d be a fool to not want this.
In your traditional vegetable garden, you’ve heard the term companion planting, which is essentially the same thing on a smaller scale, except this is under the guise of doing all of the things nature needs by selecting specific plants to mimic nature. I have a lot of problems with the concept of companion planting, especially when we start talking about the complexities of multi-species companion plantings. If you’re not familiar with companion planting, it’s a very simple— and what might seem to be common sense— idea. The basic premise is that we try to plant our crops in ways where they are able to benefit one another. For example, planting certain flowers near our vegetable garden to draw pests away from your vegetables you want to harvest. It sounds pretty straight-forward, right?
Let’s pick on the example above— now, if we’re planting aphid attracting plants near our vegetables, are they drawing aphids away from our vegetables, or are they making the whole, larger area more attractive to aphids, ultimately making the aphid problem even larger? At this point, there isn’t a lot of empirical evidence one way or the other. 1,2 Because of that, and from my own 100% anecdotal evidence, I’m not totally sold on the concept as some be-all, end-all construct. One of my first gardens as an adult was built completely on this method— I was a believer and it worked out great! But, the funny thing was, I accidentally did the exact opposite, and planted all of the things that *shouldn’t* be together right next to each other. The following year I did it again and it wasn’t a great year. So, to me, it’s proven to be unhelpful at best, and potentially damaging at worst in the sense that it might cause you to grow plants you don’t want or need, taking up space in your small garden where you could have had more productive produce utilizing the space.
While, again, there doesn’t seem to be a whole lot of evidence that it works, what’s particularly interesting to me, and points to some fundamental flaws worth unpacking at a later date (and don’t worry, we will), is how this entire concept of guilds that are developed in this prescriptive way in fact is counter-intuitive to the complex systems framework that permaculture advocates for. If permaculture is advocating for the fact that complex systems are self-sufficient and more productive, then the idea of assigning singular benefits to each plant (i.e. this is your ‘pollinator’ plant, this is your ‘groundcover plant’) is wildly reductive and linear.
Functionally, this is trying to break nature down into the sum of its parts and create a Frankenstein system— most of the plants recommended for your guild have no relation to one another in nature, and often come from different continents and, as in the example above, have wildly different soil, water, and sunlight needs. That doesn’t mean they can’t work (the example above won’t), but the logic that we are “mimicking nature” and simply swapping out parts in a machine is false, and instead, we are operating as outsiders of the natural world, tinkering with and using our limited understanding to arrogantly think we are creating a self-sustaining system with unnatural fruit trees as the foundation of it. 3
That said, that doesn’t mean there isn’t evidence-based companion planting that does work— it just probably won’t be something like, “plant X near y and you won’t have this problem you’ve always had!” It will likely be largely pragmatic with marginal benefits, benefits you likely wouldn’t even notice because they’re so slight. 4 While I’ve cited a few examples of people disproving “common” companion planting practices, the evidence that any benefits that might be experienced are almost statistically immaterial are overwhelming. 5 Most of the studies showing benefits are focused in very specific conditions that are unlike what you’re working with— massive monocrops or greenhouses— we’ll talk further about this in a moment.
One of the main reasons I wanted to discuss fruit tree management techniques before the actual planting of the fruit trees as well as what to plant around your fruit trees stems from the fact that with proper fruit tree training, light access for your understory will be much higher, and ultimately will significantly impact which plants will survive as ground cover.
So, if you do a quick google search for things like, fruit tree guilds, you’ll see a variety of suggestions—some that are extremely simple to ones that have dozens of plants. Some are designed to maximize food production—that is, every understory planting produces some food for you to eat— and others are designed to reduce tree maintenance. I’d argue both of these miss the mark a bit.
Starting with the food production guild methodology— some of the more common things you’ll see in this model reflect a permaculture method called stacking. The general idea is— think back to the forest succession discussion— highly stratified forests are more sustainable, resilient, and can host higher amounts of diversity, maximizing biomass— or, how much production— can be had on one space. So permaculturalists generally will try to apply this methodology to their 5 year old fruit tree by planting a shrub layer, a ground cover, and a root crop, and sometimes even a vine, to maximize the utility of the 10 by 10 space where they’ve put their fruit tree.
I’ve been to dozens of food forest models at this point, and these systems generally become messy, unmanageable, and often because of the layering, management of the fruit tree becomes a challenge because people don’t want to damage the understory, leading to poor tree growth— or overgrowth— which ultimately lowers fruit production from your fruit tree and lowers your fruit production from your understory significantly.
Further, by creating a diversity of foods, all usually foods that are attractive to specific wildlife, namely mammals, you’re creating a giant target for your local wildlife to come and enjoy. You’re also creating a food desert to the insects that are the foundation to our entire food web, since many of the non-native species can’t be pollinated or eaten by native species, which have co-evolved to break down certain plant chemical compounds that exist in one family of plants. 6
Certain species, like blackberries and raspberries, are almost always listed as an option to provide fruit for you while also protecting the fruit trees with their thorns, but often within a few years, these can grow unruly and take over. Besides, generally speaking, unless you’re planting a thicket that’s a few feet wide circling the tree, deer will still be able to reach around them, so they’re not nearly as effective as you might think. Another option that’s very common are blueberries, which do well in some shade, but require much different soil pH from fruit trees, so they will almost always struggle in these conditions.
In terms of a vine for your fruit tree— simply put, vines will kill weak mature trees, never mind vulnerable young trees— vines can grow quickly, even as 1st and second year plants, with growth reaching 20 feet in a year. That will kill your fruit tree— do not do it. Even if you have a mature fruit tree, if your tree was well managed and thinned appropriately for maximum fruit production, so you have those properly angled branches, the trees will be able to carry their fruit production, but not much more. Adding in another plant’s fruit and you’ll end up with broken branches, and the vine will create more shade, reducing fruit production and fruit quality.
Lastly, folks will try to use things like garlic and onions to work as a repellent to moles and other underground creatures, but alliums require high sunlight to succeed, and generally are not a good fit for this space, despite what all of the pinterest graphics might suggest. If you ignore this, you’ll often find them leaning, scrawny, and basically waiting for you to put them out of their misery. Further, if your tree is small and they do get the sunlight they need to thrive, pulling them out may damage the roots of your fruit tree which could lead to shock and stunting growth. Personally, a dozen heads of garlic or onions are not worth a year’s worth of fruit tree growth.
Now, on the flip side, folks will many times google “what does my fruit tree need to thrive” and a bunch of different nutrients will come up, as well as recommendations for and against grass and clover, as well as recommendations for and against wood chips, and so on and so on. Most— if not all— of the evidence is anecdotal. In one particular graphic I looked at, I saw 25 types of plants recommended for beneath your fruit tree, each with a specific use. How does someone even make a graphic like that and mean it?
Diversity isn’t a bad thing— obviously— but we have to remember that we want plants that can work together without competing. Our goal is that instead of competition, each plant is using resources not utilized by other species. There’s no way 25 different plants don’t overlap in where they harvest their resources, nor will they all get what they need in this environment. Think about a forest— generally speaking, the diversity per 10 square feet is not 25 different small & large shrubs, ground cover, etc. Generally, you might have a few species per layer, and I think that is where we should start. We don’t want to have as much variety as possible, but as much variety as necessary so they don’t overlap and compete. We are trying to maximize production, maximize solar efficiency, and use the strengths of some plants to keep our fruits from being totally annihilated by wildlife— if that’s realistically possible.
With that in mind, let’s start with what we do know— our domestic fruit trees need nitrogen. We can fix nitrogen in a few ways, and chances are, you’re planting a fruit tree somewhere that likely has or recently had grass. Traditional yards have a nutrient zap because we grow a species that doesn’t belong in a place where it is a monoculture, which isn’t good for resistance to disease, bugs, or for nutrient cycling. We cut our grass and take away nutrients by dumping the cuttings somewhere else, and the only way to keep our grass green and healthy is to either allow another species to move in to fix that nitrogen or to add it artificially. Either you’ve been adding it artificially or a clover or vetch has moved into your yard. Generally, my methodology is that if a species has moved into that area, help it. If you have vetch, or snow peas, or clover, or alfalfa, working its way through your yard—plant more of it (assuming it’s not invasive & not outcompeting native plants). The biological conditions of the soil are best suited for it, so work with nature. Nitrogen-fixing plants are almost exclusively from the legume family, as well as a handful of other species, but for most purposes it’s worth focusing your energy on integrating legumes.
Planting Trees
How do you plant a fruit tree? There’s so much conflicting advice out there, I want to remind you as a listener to think about what we have talked about in terms of nature. The traditional method of growing trees suggests something along these lines— dig a whole twice the size of your rootball. Add fresh compost and, depending on time of year, some fertilizer to accelerate root growth. Gently pack it down and you’re good to go! The compost is a slow-release fertilizer and the fertilizer is quickly activated in the soil to help deal with the shock of transplant. Makes sense, right? I mean, really, I understand why this methodology was followed for so long— and still is. However, when we understand the biological conditions of soil, it makes less sense. We are destroying the soil community, limiting interaction of the roots with the native biological community, and stressing the plant with the added fertilizers.
Instead, we should look to nature for an effective planting method. We want to integrate the roots into the soil community as quickly as possible without damaging them, and we want to reduce the amount of damage done to the soil by digging as little as possible. By removing as much excess soil from the root ball as possible and digging the hole as small as possible, we reduce the damage and distance between the two biological communities. If we try to mix the dug up soil with the soil we were able to remove from the root ball, we can help accelerate the process of the microbiology around the tree changing, helping the tree quickly access the nutrients in the soil. If you’re planting a bare root sapling, the same idea applies— try to slice a hole in the soil large enough for the roots to get in the ground and allow it to close right up without disturbing the soil at all.
Of course, there’s more we can do to aid in tree development, like soaking the roots in microbial liquids like JMS (we’ll discuss this another time), but for most people simply reducing the amount of damage done to the soil and getting the tree roots as close to the native microbiology as quickly as possible while doing the least amount of damage to the soil structure will be most beneficial.
Now, when you go to plant your fruit tree, you’ll likely see a line around 6 inches to a foot down where the soil content changes drastically. This is likely— again, for most folks in urban and suburban sprawl— the line where topsoil was brought in to cover the active soil in order to grow grass and live the suburban dream. If the gradient is as clear cut, you are possibly digging into native topsoil, in which case—cool! Either way, you’re able to see below this layer what your tree roots are really working with. Is it sandy? Heavy, hard clay? Rocky? If it’s sandy, you’ll want to make sure to plant ground cover and bushes that are a bit more resilient in dry conditions, and can withstand lower pH— which is common in sandy soils. Again, think about the state of the landscapes that haven’t been developed by construction; does it tend to be filled with forests or prairie, and what types of trees occupy that space. The great thing about plants like clover is that there is a large range of clovers to meet the demands of different soil pH’s, so you can likely find one for your particular needs. Further, if you remember from the soil episode, we had talked about how sandy soil does a poor job of retaining both water and nutrients, so it’s worth thinking about what types of plants thrive in those environments— hint, there’s plenty of native ones that can also be productive food crops (like blueberries or spicebush).
If your soil is clay-ish, plants that can do better in more moist conditions are helpful, and it’s worth considering using plants that do well at breaking up compact soil—native roots like sunchokes and sunflowers are really great for this.
Now, what if that topsoil is very thin? You’ll want to build it up, because that’s where the biological community that helps nutrients become accessible for plants live, so it’s imperative to grow topsoil as quickly as possible, since your domestic fruit tree is going to need optimal conditions to be productive. In a future we’ll be doing in the future on pasture management, we’ll cover some of this in much more detail, along with some of the specifics on pasture grass, grains, and so on— but we need to try to build up the biomass for the soil in a way that reflects the natural process of soil-building. The way we do this is pretty straight forward, actually.
Much like in nature, our goal is to build soil using a mix of things that break down at a variety of speeds— such as leaf litter, small scraps of soft vegetables and fruits, as well as natural products with higher lignin content— that is, woodier material. We can mix natural compost, if you are composting your food waste with local leaf litter and mix it up with these other materials, which generally includes more leaves, paper, cardboard, and wood chips, to create a covering for the soil which gives access to the content to the biological community already within the soil, as well as introducing other biological communities from your compost, which have thrived in the compost pile because they accelerate at breaking down those particular types of matter, to help accelerate the process. The largest pieces, the wood chips, can take up to 5 years to break down, which might sound like a long time, but is actually an extremely quick process because of the high surface area of the wood chips, versus a log falling in the woods, which can take up to 100 years to break down. The added benefit to this method is that the litter coverage of the soil also retains moisture within the soil, reducing your need to water, while also helping build the soil’s organic matter. Your first thought might be, well I know that wood chips are easy to come by, but why not accelerate the process of building biomass by only using low-lignin materials? Then it will break down quickly, building my soil more quickly? That’s a valid point. And the answer is complicated, so I apologize in advance for the next paragraph.
Relative to most other plant derived organic substances, lignin is more resistant to mineralization by soil microorganisms—it’s tough to break down by the biological soil community. The resilience of lignin is due to the fact that only a few micro-organisms (i.e. white rot fungi and a few bacterial species) can completely degrade polyphenols— that is micronutrients— and can break down complex molecules into small, more accessible ones, a process called catabolism— all of which is required to fully break down plant lignin. Consequently, lignin directly and/or indirectly influences soil microbial community structure, which in turn controls soil quality through the provision of several key ecosystem services. It reduces the emissions of greenhouse gases from soil, retains soluble nutrients, promotes soil aggregate formation— that is, those networks formed by the fungal community— and helps them stabilize, reducing soil erosion, and creating bioremediation and detoxification of natural and man-made pollutants. 7 So, yeah, incorporating lignin into our soil biology, while somewhat inconvenient, is super important, right?
Now, if you’re looking to build that biomass on your soil quickly and without using extensive, external inputs, it’s worth looking for leafy perennials that respond well to getting cut down. That’s why one particular plant that is popular in permaculture has become so popular— comfrey. It’s leafy and grows quickly, and responds well to chop and drop— the name for cutting plants down and using the leaf litter to cover the soil. That said, there’s multiple cultivars, and the popular, aggressive one is non-native and can take over, so I don’t really recommend it. However, leafier perennials and work as great biomass accumulators, or even better— find places with leafy invasive species like Japanese Knotweed or Kudzu and chop them down. You can help combat invasives while also building your own biomass. While Japanese Knotweed has a reputation of spreading anywhere green leaves touch, the evidence suggests that they can only grow from a root, but if you’re distrustful, let the plant dry out before applying. Other invasives can have allelopathic traits, so make sure to check what the science has to say about the material you’re trying to work with!
What’s the Science Say?
So let’s change gears a little bit— we’ve covered the need to build soil, how we can do that, the need to make sure your domesticated fruit trees are getting nitrogen from plants. What are some of the other goals of common guild setups, and are they based in any scientific evidence?
One area that has seemed to garner attention is the idea of creating pollinator attractors to maximize fruit production. The theory goes that by creating flower-heavy guilds, we can attract more pollinators to your fruit trees, ensuring each flower will be pollinated and will produce fruit for you. Dill, fennel, chamomile, fennel, purple coneflower, yarrow, and mint are common recommendations for pollinator pairings for fruit tree guilds. Makes sense, right? On the surface it absolutely does, but let’s think about it a little deeper, and I’m going to pick on apple trees, since they’re the most common fruit tree in the United States. When do those herbs usually flower— they usually flower in June and July and some even in August, while apple trees typically flower in April through May. Taking a few minutes to think about these methods highlights some of the inconsistencies in this type of theory. While there is very limited and specific evidence of using companion planting for increased pollination, given those limitations, there’s very little reason to try it.
So, what would I suggest, if you’re pollinator-curious? Pick some perennial flowers that bloom at the same time as your fruit tree would be a good start. Further, try to find flowers that feed generalists or, ideally, are pollinated by the same pollinators as your fruit tree. Frankly, I’m not knowledgeable enough to speak to how common this overlap in pollinators is, although I’m guessing you’ll rely on plants that are most utilized by generalist pollinators to be successful. Keep in mind that in complex systems, while many flowers can be pollinated by multiple species, there are specialists that will only be able to pollinate certain sized flowers, so there’s no benefit in attracting specialists that can’t pollinate your fruit tree, right?
Natural Pest Protection
The last area that is common is really two, but I think they fall under a dichotomy of good and bad— and that’s along the lines of attracting good insects and repelling bad insects. The one most folks are familiar with are marigolds near your tomato plants, which supposedly deter whiteflies or attract aphids away from your fruits. Now, if you google it really quickly on the internet, you’ll see that there will be articles— and I’m not going to point fingers at particular publishers— that will say stuff like “science has proven this old wives’ tale is true!” I want to give you a few sentences from the abstract of the evidence of this, to help frame up the questionable nature of how evidence is translated. The paper is entitled Companion planting with French marigolds protects tomato plants from glasshouse whiteflies through the emission of airborne limonene.
“Here we present two large-scale glasshouse trials corresponding to the two main ways growers are likely to use marigolds to control whiteflies. In the first, marigolds are grown next to tomato throughout the growing period and we quantify whitefly population growth from the seedling stage over a 48 day infestation period. Here we show that association with marigolds significantly slows whitefly population development. Introducing additional whitefly-attractive ‘pull’ plants around the perimeter of plots has little effect, but reducing the proportion of marigolds and introducing other non-hosts of whiteflies (basil, nasturtium and Chinese cabbage) also reduces whitefly populations on tomato.”8 In other words, using those ‘pull’ plants; that is, plants that are supposed to attract the whiteflies away from the tomatoes, have a negligible effect, while marigolds release a specific chemical in the air that is measurably effective in an isolated situation. Whether or not it has any meaningful impact in a garden is anecdotal at this point, but again, I think it’s worth being aware of the arguments made in defense of companion planting, and even when there is research done, how that is translated by journalists.
With this in mind, let’s talk a bit about this concept within the context of fruit trees. What recommendations are there, and what is their purpose in the guild? Generally, these plants that are meant to deter bugs are smelly plants— things like yarrow, mint, bee balm— which is a mint— fennel, garlic, onions, tobacco, among others. I feel like this episode is becoming a weird mix of research and gardening, because there’s so much fake information out there on the subject since it overlaps so heavily with naturalism, which relies on natural fallacy for evidence.
Again, if you google plants that repel bugs, finding primary source documents is near impossible. There’s even a wikipedia page just about plants that repel insects, and the sources are mostly spotty newspapers and gardening websites— very little of it is based in actual science.
So what actually has evidence? Some research was done in 2011 to analyze the new trend of plant-based repellents, titled “Plant-based insect repellents: a review of their efficacy, development and testing”, which seems to be the only research I could find without access to JSTOR or another research portal, and there is some evidence for thyme and mint being effective. That said, it was focused on mosquitos that we don’t like, not the ones plants don’t like.9 There isn’t much evidence for any of this at all. That said, I would make the case that mimicking nature, as in, creating a diverse array of plants, without going over the top, of course, is a good way to limit the risk of one particular pest being attracted to your fruit area. Again, I’ll reiterate, it’s important to plant species that won’t inhibit your ability to manage your primary concern— the fruit tree.
You’ll notice I didn’t mention having a shrub layer at all, despite comparing all of the other areas covered in most permaculture fruit guilds. There’s a reason for this. Well, actually, a few. The first is that permaculture guilds don’t usually require them for any benefit of the tree, but rather as a benefit for you in terms of fruit production. So, in terms of science-based planning, there’s really nothing to argue here, it’s a totally optional thing to include. Think quickly to your most recent hike— how many bushes were directly below a tree? Typically, the bushes you’ll see in these spaces in temperate climates are thin, like blueberries, unless they’re on the forest’s edge. Thickets are an entirely different situation, one we’ll explore at a further date.
With all that said, it’s important to remember that if you do plant a shrub, you’ll have to work around it when you’re pruning and harvesting. If enough sun is getting to the shrub layer for blackberries to grow directly below your canopy in any meaningful volume, your canopy is probably on the verge of being too thin. There are a few fruits that do okay or even well in the shade, but I am cautious about the idea of planting fruiting understory beneath a fruiting tree just for fruit’s sake, given the fact that in ecosystems this is a fairly rare practice.
This also raises an important question about intent, right and sense of place. When we make decisions about planting diversity, there’s nothing inherently wrong with planting species that provide us with the foods we love. However, what is becoming more and more common is planting species simply for the sake they produce food, instead of understanding the implications of the decisions we’re making on the landscape. I might be making a mountain out of a mole hill, but fundamentally we’re talking about our relation to the systems around us.
When we plant things solely for our benefit, but not necessarily because we desire those things but because we believe that any improvement on behalf of human interests are more significant than the needs of the greater ecological system around us, we further separate the natural world around us from the work we’re doing, despite the fact we may be outside and getting our hands dirty. Planting fruit bushes or other edible crops that we likely won’t eat because it’s an edible crop, with no consideration for reciprocity with the ecosystem which makes those plants survive and thrive, perpetuates a division between ourselves and the ecology beyond the tree guild we’re building “in order to improve the ecosystem around us”. Taking just a second to consider the needs of the ecosystem, and to consider that some of the work we’re doing should go back to the ecosystem, regardless of our benefit, is the first step in decentering human needs and working to align the needs of the ecosystem with our own.
It might seem like I spent an entire episode saying “it’s all bullshit”. Well, it isn’t all useless, but I think the natural movement, especially the permaculture movement, is so focused on articulating the benefits of using nature to effectively manage our gardens that it gets swept up in trying to prove things that aren’t true and focusing on a *wow* factor. Plus, I mean, who would come take their Permaculture Development Courses if they didn’t have all the answers to everything? The naturalist fallacy— that is, the idea that natural is always best, is a slippery and dangerous slope.
Which brings me to my final point. I don’t have the answers for everything, and anyone that claims they do is probably a bullshitter. While all the information I presented here is based on my own research— the reality is that a lot of these methods are by design not scalable, and that isn’t typically profitable, and our research tends to focus on areas that are profitable— primarily maximizing monoculture crop production.
So, this is a quick little primer about how you want to think about what you’re going to put around your fruit trees. Unfortunately, it’s not a simply plug and play like Youtubers and permaculturalists sometimes like to suggest, and each conditions require different plants. Further, you have to be realistic about the amount of time you want to invest in maintaining your system, and what are your goals— do you want to maximize your fruit tree production and everything else is secondary, or do you want to get a variety of fruit, maybe not at peak production efficiency, but with a healthy variety and a support of your local ecosystem’s needs?
Everyone’s situation is unique, and that’s okay. You might think you’d rather be safe than sorry and follow companion planting methods—that’s fine. What works for you might not work for other people, and vice-versa. The key point is to keep in mind how your decisions impact the ecological community around you.
I generally like to look to how trees existed in nature as a guide, and if nature isn’t readily available, to how these species were managed historically— even specifically during what we typically call ‘pre-history’. So, for apple trees, it makes sense to look to places like Kazakhstan, one of their native lands, where they are grown in silvopasture alongside walnuts.10 These trees are grown in massive tracts together with a mix of other various native trees, and the understory is largely wild grasses, clovers, and other short annuals and perennials. So that’s why I try to mimic, while also trying to maximize nutrient availability and soil health for my trees.
Despite the arguments by many gardeners that grasses compete with fruit trees for resources, fruit trees evolved with grasses to encompass the same environment, so I don’t think it’s as large of a problem as some folks would like you to believe. The biggest arguments against grass is that it competes with resources and it can harbor pests if it starts to get very long. Oddly enough, these are the same arguments against mulch. The alternatives are chemical application to kill everything below the tree, including the microbiology in the soil, and plastic covering of the soil. I’d like to unpack this real quick, and make the point of why having some kind of livestock is so beneficial— they can work to keep your grass short, return nutrients to the soil, and eat any rodents that show up and try to compete with them for that food. There’s nothing you can do about those issues with mulch, so to me, grass seems like the clear winner, with a livestock caveat.
This example I brought up of the apple and walnut forests brings up the concept of superguilds, which, in case the name doesn’t totally give it away, is the idea that multiple tree guilds together create larger guilds— guilds of guilds. Yeah, I’m getting tired of that word too. There doesn’t seem to be any cohesive suggestions in the permaculture world of what benefit these superguilds have-- the only usually refer to them in order to use them to create things like wind borders and to create buffers between various tree guilds that don’t do well together, and oddly enough, the common example comes from Toby Hemenway’s book Gaia’s Garden, which is Apple and Walnut guilds. Walnuts release a chemical called juglone, which decreases competition from other plants by stunting or killing them, and he suggests creating a buffer for fruit trees from them.11 Oddly enough, walnuts and apples grow natively together, so I wouldn’t take this piece of advice. I will say, despite that nugget, his book is pretty good, and I do recommend checking it out if this is all new to you.
Our understanding of what can and can’t be done, at this point, is so shallow. We may be able to study galaxies far away, but we barely understand the soil beneath our feet. All of this is just a guideline based on what we know. As stewards of the land, we must take the scientific knowledge we have and compare it to the historical and anecdotal evidence we are given to see what does and doesn’t make sense. No one has the answers, and we are relearning many skills we had once taken for granted for a millennia. Take your time, don’t become too overwhelmed, but have a good foundational knowledge to go into these subject areas with your eyes open. And have fun. Have fun planning, and planting, and tasting the produce you create. And hopefully, maybe, we won’t have to do this just to survive, but to thrive.
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I have personally been victimized by YouTube videos entitled “how to plant trees for MAXIMUM yield” and then proceeded to watch some dude dig a hole for ten minutes :/ as always thanks for all your hard work and research!
This was a very well written article. I'm new to gardening in general, and this helped me think about the logic behind potential choices and what results I actually want to prioritize.