This is the fourth diary in a series on ecological gardening that I am writing for the Practical Survivalism and Sustainable Living group here on Daily Kos.
The purpose of this diary series is to share my limited knowledge about a revolutionary mindset that is nothing short of a paradigm shift in our relationship to the natural world. What this diary will not be is a definitive, earth shattering work that claims to understand everything. What will be described here is not "Finchj's way" but rather my understanding of agroecology & permaculture and how I tried to internalize and apply it.
The first diary can be found here; the second, here; and the third here. As this form of land stewardship is knowledge based, I highly recommend readers to follow the series through- at least reading the diaries with "Introduction" in their title.
I will include an introduction simliar to this one in each diary for sake of continuity and disclosure.
I want to stress that ecological gardening is possible without formal training and is a DIYer dream. Nature will teach you everything you need to know, but since we have limited time here on earth, my aim is to share what I know and where I learned things so the growth will be exponential.
Last time here...
In the last diary, I looked at the most important neighbor any plant has: the soil. Instead of writing a very technical diary revolving around soil types, the soil profile, pH, etc., I decided it would be better to describe three techniques that ecological gardeners use that revolve around respecting soil. As you may recall, soil is the most biologically active part of a landscape. The numbers of organisms are staggering- reaching billions rather quickly. The three major ways ecological gardeners respect this soil life are: mulching with organic matter, plant cover, and pathways (in other words, avoiding soil compaction).
The diary was a little more hands on than I wanted, but soil is just so complicated that instead of reinventing the wheel and throwing out a lot of knowledge I chose to share some common soil building techniques for the sake of brevity. I just finished reading Teaming with Microbes by Jeff Lowenfels and Wayne Lewis (h/t to the fan man for mentioning it in the comments last diary). It does a good job informing us about the soil life, although some of their recommendations I shy away from.1 If you want to know more about what is going on, check it out from your library. Of course, a cursory internet search will teach you more about soil science as well.
Right: July 7, 2011 Preparing some compost tea: a biologically rich "fertilizer" made with on site materials. Compost teas help bolster soil life while returning nutrients to the soil.
As this introduction progresses, we will be taking an ever wider perspective of the garden. The fundamental topics of this diary are the different "layers" that make up a garden.
1. In general, the book was great. But, was definitely geared towards organic gardeners, not ecological gardeners. Which is totally fine. I hope that as this series progresses, the difference between the two will become more apparent. Once I finish with the "introduction" section, I'll have a diary that will make the case all in one place. Anyway, at one point they mention replacing soil (big red flag). In some others, they mention not using manure (fear of E. coli) and dealing with "weeds"- which I've already said do not exist. So just be aware that this is not a diary series on organic gardening. Ecological gardening goes beyond organic as it is commonly practiced.
Jun. 16, 2011. This photo does a pretty good job showing different layers in the garden. Different microclimates are easily discernible. Notice how the each plant fills the physical space in the garden. Imagine the cool air at the vantage point in contrast to the hot summer heat bathing the garden.
Basic Garden Ecology 3: Layers
Breaking with convention, ecological gardeners design through all the "layers" plants make available to us. Ecologists and ecological gardeners divide this physical space into different numbers of layers. Personally, I have a better time understanding this with a picture.
This is my personal adaptation of "Figure 3.2 Forest garden vegetation layers..." from Edible Forest Gardens vol. 1, p. 71 by Dave Jacke and Eric Toensmeier. I have added the successional timeline.2
From left ("early") to right ("late"), we have the mulch/humus layer, ground cover plants (up to 3'), herbaceous layer (up to 6'), shrub (up to 12'), low tree (up to 50'), and tall trees (50'+). As time "progresses" and the ecosystem "matures," one can expect taller, larger trees to dominate the canopy.3 An understory develops to meet changing availability of light, water, nutrients, pH, soil biota make-up, and other factors. Whichever plants populate the overstory (that is, the tallest plant regardless of height), they have a profound influence on the understory.
All plants influence the soil profile, with plants either sharing space cooperatively, or competing for space. Knowing the root habits of plants allows us to design in this hidden, but highly important, layer. The root types of many plants are unknown, which can allow back yard gardeners to participate in adding to our knowledge about these species.
Each layer has different functions in the garden. For instance, the canopy absorbs most of the sunlight- creating a microclimate below that is both cooler and typically more humid, greatly affecting the range of species that can thrive there. More than that, "different tree shapes and branching angles direct raindrip to the edges of the tree crown, or down the trunk to the soil, or they may scatter it evenly under the branches."4 Every other layer has to deal with the new conditions set by the overstory, which can include multiple species whose compounding characteristics challenge us as designers.
In a typical garden, we see the use of maybe two of these layers- the ground cover and herbaceous.5 Very rarely do gardeners incorporate taller perennials and even fewer consider utilizing microclimates. If a tomato packet says "full sun," then we sow the plants out in the open- unprotected- to weather a full 12+ hours of solar radiation and withering winds. Shade is anathema in a personal garden. Shade in the community garden becomes a point of contention and quarrels. "Your sunflowers are shading my tomatoes!"
Shade must be avoided, we are told, because it decreases yield. Ecological gardeners embrace shade and sun with full appreciation of the microclimates created by different layers in the garden. In keeping with the permaculturalist mantra of "stacking functions," ecological gardeners design their gardens from the canopy on down to the depths of earth. Niches (remember those?) are filled and the garden begins to burgeon with diversity.
2. Dave Jacke and Eric Toensmeier, "The Five Elements of Forest Architecture" in Edible Forest Gardens vol. 1, (White River Junction, VT: Chelsea Green, 2005). This chapter served as my main source here. As I am only offering an introduction to these topics, my aim is to fall within fair use. Because I personally feel that their work is valuable and protected, please inform me with any concerns with regards to intellectual property rights.
3. Succession does not follow a linear path to what we would consider an "old growth forest." Not all landscapes are the same, not all climates allow for a forest, and above all, the classical notion that there can be a stable climax archetype for an ecosystem is challenged by the constant disturbances created by natural forces- as well as man.
4. Ibid, 72.
5. "Typical garden" refers to vegetable gardening.
Jun. 14, 2011. The beginning of a favorite, the four sisters. While our experiment with the four sisters failed miserably due to a huge error on my part (I'll share that at the end with a picture), this is about as far as most gardeners are willing to push their use of layers. Corn and sunflowers act as the overstory and support climbing beans while squash and cucurbits shade the soil.
Stacking Functions to Redefine Yield
Stacking functions requires us to redefine yield to account for more than the amount of fruits and vegetables produced for human consumption. Yield becomes holistic. The nitrogen fixed by the bacteria in association with, say, Trifolium repens (White Dutch Clover, pictured left) is only part of the total yield from this species. It also acts as a generalist nectary plant throughout much of the growing season while serving as a living ground cover that can withstand foot traffic, making it a great species for pathways. All of these functions stack to create a yield beyond just nitrogen fixing. And that is just but one plant. When we begin to count the functions in a polyculture, the yield count is driven up further. A well designed guild that features well thought out polycultures sees yields increase dramatically.
While it is true that a species sharing resources (especially sunlight) will produce less in the conventional sense, "...in the forest garden [or any landscape], we need to evaluate the yield of the whole system, rather than the yield of only one part of the system. In the forest garden, you may harvest raspberries, apples, [...]. You may also "harvest" labor-saving "yields" like weed control, beneficial insect attraction, and soil fertility improvement from the garden community."6 As a system, a temperate forest can produce up to "5,850 kcal/sq. m./year" while agricultural land turns in about half that at "2,925 kcal/sq. m./year."7
So it begins to make sense, then, why ecological gardeners and those who practice permaculture strive to create whole systems that resemble forests or woodlands, while taking advantage of the changing microclimates at their disposal while succesion takes place. With twice as much energy being captured, the system becomes productive enough as to allow for the diversion of energy from a narrow definition of human needs to the needs of the ecosystem.
The concern about conventional yield is invalidated when we consider that by outsourcing the production of fertility- as many gardeners and especially agriculturalists do- the price is paid elsewhere. When we take into consideration the costs of these external inputs, especially industrial ones, the much touted "efficiency" crumbles.
Let's think back to those tomatoes we put out into full sun. How do they look during the heat of the day, when the temperatures are climbing into the 90's and beyond? Ask anyone, even a child, and the first word that comes to mind is sad. Whether or not they are truly sad (which I believe they are in their own way), they are stressed. Stressed plants release hormones that "pests" hone in on and attack. We don't want stressed plants, we want healthy plants. Allowing the tomatoes a respite from the summer sun will save you and your tomatoes a lot of problems. They will require less water. With lower levels of stress, the tomatoes will be healthier and resist pests and disease better. This will result in better, but not more, fruit.
Better yet, when we can design systems that accept this decrease in fruit production in exchange for even more ecosystem services. The more layers we utilize, the more edges appear. Edges increase connections between species and elements, which results in greater complexity. Complexity and diversity go hand in hand towards renewing the fabric of life.
6. Ibid, 31.
7. Ibid, Figure 2.2, 31.
Nov. 9, 2011. Volunteer tomatoes (center) grew under near full shade conditions without watering during the summer. We did give them some compost tea a few times, but not nearly enough to keep them alive should they have been in full sun. Come fall, with the low sun, they were in position to absorb more energy and began fruiting. Due to its very dense crown, the willow oak (Quercus phellos) may have been acting as a heat trap.
Through the utilization of the many layers available to us, we can design and foster the growth of ecosystems that mimic natural systems but with an emphasis on human uses. Redefining yield to better reflect the totality of ecosystem function allows us to be honest with ourselves about what it takes to survive. Soon, we will be going beyond the vertical layers and designing through time as well as space to appropriately stack functions.
This requires intimate knowledge and thought to design. Which is why these diaries can only serve as an introduction to these concepts.
The next diary will cover either polycultures and guilds or nutrient and water cycling. I haven't decided yet which should come first.
I mentioned that I would share my failings. Well, here is a picture from June 29, 2011 of our four sisters guild:
Horizontal corn and sunflowers are never a good sight.
We had been experiencing near drought conditions which were only broken by episodes of wild weather. Intense storms brought downbursts (straight-line winds) reaching 60 mph. So, why was this a failure on my part? Well, I hadn't planned our corn planting correctly and soaked our kernels too early. The weather forecast was revised to bring us a cold spell and I was forced to either attempt to dry them out or plant them in flats and transplant them. Transplanting corn is a horrible idea because they fail to develop strong taproots when put into the garden. Without a strong root system, they were tipping over even when winds were a "low" 30-40mph. With the corn gone, the patches became a tangle of melons and beans- who then became competitors for space. Ah, well. You learn something every time. We'll probably try this again in the spring, but on a smaller scale.
Thanks for reading!
(This is just copied from my last diary, I'll make it more comprehensive in the future)
My favorites books:
Edible Forest Gardens, Vol I and II. David Jacke with Eric Toensmeier. Chelsea Green, 2006. Sepp Holzer's Permaculture. Sepp Holzer, translated by Anna Sapsford-Francis. Chelsea Green, 2010. Yes, that is an Amazon link... not my fav but it'll direct you to the book.
Gaia's Garden. Toby Hemenway. Chelsea Green, 2009 (2nd edition).
Let the Water Do the Work. Bill Zeedyk and Van Clother. The Quivira Coalition, 2009.
The One Straw Revolution. Masanobu Fukuoka. Link will point you to a decent review.
For a much fuller list of books on the subject, see Toby Hemenway's Permaculture Reading List. The article I linked to up top is also a great read.
There are plenty of materials online as well. The Permaculture Institute of Australia is excellent.
Youtube has plenty of videos. If you want to see a slideshow of our garden from the first part of last year, click here.
Edit: I'm cleaning up some of my awkward/sloppy word usage. I wrote this all in one go, instead of over a couple of days. Hope everyone is enjoying their Sunday!