Part 4: Wind and Sun (Part 4 of 5 of the Article Series Titled "What is Forest Gardening?")
Updated: Mar 23, 2019
In the earlier two articles, we looked at structures in forest gardening and how they relate to functional space when integrating designs. We discussed flow, waveform, natural patterns and other elements of design in forest gardens. Walkways with branching intersections allow for wheelbarrows to wheel around pre-existing structures, with the intention of organizing all the areas of the garden. Functional space, storage areas, and other spaces are also necessary. Still yet, we need to leave some ground for future intentions.
Clearly there are advantages to using stone materials for drainage, permanence, solar heating and storage effects. Materials and designs for wheelbarrows themselves are other important considerations when working on larger projects. We now turn to the subject of light and air in the forest garden.
Please see the slide presentation Click here to open slide as pdf (slide #26) from the talk "What is Forest Gardening?", with a set of diagrams showing the microclimate effects of wind and sunlight on microclimates in the forest garden.
AS LIGHT AS THE AIR WE BREATHE
Simply put, microclimates have a lot to do with light and air. The colour coded isotherms on weather maps appear surprisingly similar to contour lines on a topography map. Zoning in the garden is in some ways a topography of climates and function. Zone maps showing different climates are often in gardening and forestry texts. It is possible to see overlap between the microclimate maps and how to figure out the border placements of the forest gardening zone spacing. The proper spacing for all the plants connects with zone spacing.
While missing a physical material presence, light and air together fill the spaces in our growing areas. They provide the plants breathing spaces. The canopy and sub-canopies of the garden must remain open enough to keep mould growth in check. Designing productive livings spaces should ensure that tender fruit and flowers will breathe adequately to thrive. We must also be sensitive to their needs when planning for all the other structures or the balance between the needs of a shared space. It is okay to try and add lots of plants but if they're not able to be provided for their needs, how will they succeed fruiting or being raised in a nursery?
For this reason, we are looking at how the structures interact with sunlight and wind. The diagram showing a forest with wind effects and the cooling temperatures, and higher humidity inside the woods (see slide #26).
THE FOREST GARDEN AND THE GARDENER, FEEDBACK LOOPS
It's hard to forget the persistent needs of plants until they finally appear content. Even then, a new goal continues by keeping them happy and producing well. From both a personal and business sense, as Eliot Coleman points out in The New Organic Grower (1995), an emphasis on quality is what counts. As he describes, perhaps then, the market will take care of the rest.
Tending to a forest garden means checking up and dealing with what needs arise. The forest gardener should be coming and going to provide for the plants in the surrounding. Ancient Chinese proverbs were once written about the "black gold" of plant care as the shadow cast by the gardener.
By emphasizing the importance of structures in space early in the earlier articles in this series, it's possible for us to underestimate the essential role that people that play in the design and maintenance process. In forest gardening, it's not about leaving everything to the pre-destiny of structurally well-designed microclimates. In a practical sense, a well thought out design is just as important as the person working can implement it. But the reverse is also true; the forest gardener on the job should be directing the future of plans as a self-correcting process or the system under development will never reach its potential.
Together the goal is to design a process-oriented feedback loop. All this relates to management practices. Richard Florida points out repeatedly how Toyota automakers were able to improve on their production lines (and car reliability ratings). He explains how Toyota created its success in part through a feedback loop with those working in production on the factory floors that gave them a competitive advantage.
FOREST GARDENS AS LAYERS OF LOOPING HIERARCHIES AND COMPETING DIVERSITIES
It doesn't make any sense to ignore the natural hierarchies. Think of untamed jungles that forest gardens will naturally try and grow to become. Look at what plants want to grow vigorously and can fruit well consistently. There are real forms and different kinds of dominance that also have feedback loops. It is a matter of survival.
It is far better to learn the difference for yourself. The garden truths must be learned on an individual basis, (such as finding out about the wrong soil, timing, disease, excess or inadequate drainage, etc). Knowing and fixing these issues to correct the feedback in the system is essential.
Amidst all the hype over diversity, at times there can be too much hype and less actual work in accomplishing it. While offering more good than harm in most cases, diversity complicates things and can be more expensive. Structuring layers in a garden complicates the design to model forests, and adds functions. Without question, expect some things to flourish where others don't. Once the dust settles, keep hold of what's working and selling, then build off it. Using a targeted approach, look at related species and test our different varieties in a process-oriented way. Often simple, less flashy solutions can be all the difference.
QUALITY STRUCTURES, TOOLS AND SKILLS IN THE RIGHT SPACES OVER TIME
In the same way that a craftsperson wouldn't rely on weak tools for their best work, a gardener requires skills, physical ability, endurance, and perseverance. Quality should be a significant determinant. The limits of quality relate to access to many needed materials, including skilled labor. Like tools, the use of the space must be positioned, timed and brought together with the elements. The degree and amount of forest gardening efforts change so much over time during its development and requires a changing skill set.
What is true of skills and materials applies to time. Going out into a place once or year will only go so far to provide a person a sense of place. It takes years to get to know garden spaces and their neighbourhoods. This time to understand something applies especially to multi-storied forest garden spaces that house many plants and other wildlife as different stages of growth.
SUNTRAPS AS UNIQUE GROWING SPACES
Wind and sun influence design when creating microclimates. We will later explore examples such as shelterbelts, sun traps, walled and freestanding trellises. These structures create great growing spaces in the surrounding environments and collectively work to improve growing. Fencing was used in many cultures to block wind, trellis, and create a small microclimates, especially in the front. In the book Gaia's Garden, there is an excellent diagram of the suntrap and shelterbelts (see slide #19 in the presentation). In the suntrap model, part of the design acts like a shelterbelt that protects an open centre. Suntraps benefit forest gardens as a compromise between the different forms that uses sun exposure and wind protection.
LIVING SHELTERS IN THE WIND STORMS
Shelterbelts help by creating leeward protected edges. Exposure tolerant, vigorous trees for hot dry weather make good choices. The density of the pattern will depend on how strong the wind is, and the kinds of plants we choose to build it with. Often, shelterbelts make useful homes for native fruit and nut trees and shrubs. We can gain unwanted pests in some cases. Consider some kind of integrated pest management.
Think of how much food we could produce if we could grow along the edges of under-used borderlands. Community forest gardens and other projects could go a long way towards feeding their local populations at risk or in need.
Unless we are thinking of edible pine trees and juniper berries, there are not as many edible evergreens when considering shelterbelts. Writer and gardener Niki Jabbour discusses how much of an effect evergreens in particular can make for Winter and off season protection for vegetable growing in The Year-Round Vegetable Gardener (2011).
The Ontario Ministry of Natural Resources' Extension Notes The Benefits of Windbreaks (1994) points out the problem of wind and soil and the erosion effects. Offering protection helps in many ways but has unwanted side effects. For example,winter evergreens like white cedars are amongst the most dense and popular trees for protection. However, cedars can attract mosquitoes from this density.
LIGHT AND AIR AROUND BERMS, SWALES AND WATER
The design for berms surrounding swales works similarly by disrupting the wind flow that again creates protection. Use of wind changes over water to cool the air and moisten it, and the sun provides solar gain to the mass of water. There is gain from solar reflectance off the water, especially on the North banks. The heat of the day retains warm overnight time air temperatures. Sepp Holzer explains this very clearly in his book Sepp Holzer's Permaculture: A Practical Guide to Small-Scale, Integrative Farming And Gardening (2011). His work outlines this concept with diagrams (see slide #21 of the woman standing upright as she gardens on the mound). Hugelkultur can be a practical and responsible way of managing garden debris on a small scale.
Along with other permaculturalists like Geoff Lawton, Sepp Holzer worked on large scale projects worldwide in the past. Land contour, the degree of slope and its orientation influence air flow and lighting. Lighting and airflow are complicated by seasonal changes in illumination. Seasonal changes are part of the reason why sectors (as discussed in the earlier article about zone and sectors for functional space) are so important.
FOREST GARDENS AND THE SCOUTS WITHIN
The living spaces of sunlight and air come and go with the movements of creatures that live there or are just visiting. These scouts of sorts are a tremendous help with things. Their values in finding vegetable, nut, and fruits eating pests are as worthwhile as in any other field. Pets and other animals can offer all kinds of benefits to growing spaces. Mark Cullen in his Canadian classic gardening book All Seasons Gardener (1998) discusses how cats naturally lounge in the warm areas in the garden. He explains plants growing zones and microclimates for those starting. Other mammals, reptiles, and birds all can be used to understand the patterns. As Patrick Whitefield described in How To Make A Forest Garden (1996), animals and other creatures deserve as much a place in the forest garden as we do.
Begin by observing where they are first, then try and understand why they're there. Plants can perform similar scout-like abilities. In the plant realm, Sepp Holzer has a lengthy discussion on the types of native vegetation will tell us about the soil chemistry and its nature. Have an eye for the scouts in your forest garden. Pretend they know more than they tell you.
WIND AND SUN: SUMMARY
In this fourth article of the "What is Forest Gardening?" series, we highlighted how existing forest garden designs work to create microclimates by changing sunlight and air circulation. Both sun and air work together with slope, exposure, and structures.
Feedback loops operate as elements of design. Zones and sectors regionalize the forest garden and help to distinguish between spaces. We lightly touched on practical considerations related to pruning, observing, and a selection of plants. We shared the advice of many expert gardeners, designers, and permaculturalists.
Suntraps and berms surrounding swales and ponds are examples where sun and wind make microclimates. Lastly, we discussed how many living creatures could act as scouts that tell us about what is coming and where things are going in the forest garden.
Coleman, Eliot. The New Organic Grower (1995) Chelsea Green Publishing
Cullen, Mark. All Seasons Gardener (1998) Penguin Canada
Hemenway, Toby. Gaia's Garden, 2nd Edition. (2009) Chelsea Green Publishing
Holzer, Sepp. Sepp Holzer's Permaculture, A Practical Guide to Small Scale Integrative Farming (2011) Chelsea Green Publishing
Jabbour, Niki. Year-Round Vegetable Gardener. (2011) Storey Publishing
Whitefield, Patrick. How to Make A Forest Garden (1996) Permanent Publications
Ontario Ministry of Natural Resources, Extension Notes: The Benefits of Windbreaks. The LandOwner Resource Centre, University of Toronto's Faculty of Forestry.1994
Noted reference: Geoff Lawton is a renowned pioneering permaculturalist and has been a speaker at TED talks.