GT Interviews #21: Eric Toensmeier - Part I

I’m really excited about having connected with Eric Toensmeier for an interview of sorts, as he answers questions posted by our members.

Eric Toensmeier is the author of “Perennial Vegetables” and shares his wisdom and experiences not only in his book but on his website and in his videos as well.

For me, he is one of today’s experts on permaculture and is an inspiration to gardeners everywhere.

Eric Toensmeier (photo from his website)

 

This is “Part I” of the interview.

GT: 1. When creating a backyard food forest, the resources and materials needed can become a daunting task to assemble. Have you learned any trick or tips that would help to manage the project more efficiently based on your past projects?

Eric: Well, you don’t need to do the whole thing at once. Even in our small backyard (1/10 of an acre), it took 3 or 4 years until we have planted the whole thing out. So doing one patch at a time is affordable, and also effective because it gives you a chance to learn from your mistakes and see what grows well, tastes good, and to learn effective species combinations for your site all at a small scale.

Martin Crawford’s Creating a Forest Garden is a fantastic book with some very good establishment strategies. Martin planted his trees first, and mulched underneath them with temporary landscape fabric with wood chips on top. Meanwhile he was propagating the large numbers of understory species needed to fill in under the tree layer from seed and cuttings. Each year he was able to plant out a large area very densely which had been made weed-free with landscape fabric.

Finally I think for larger areas or simpler management keep a simple understory. One of the simplest is to run livestock under your trees. Even in a small garden you could run geese or chickens through rotational paddocks of fodder plants. This can provide meat and eggs as well as a boost to fertility and pest control.

 

GT: 2. Again looking at larger projects, the number of plants required cover larger spaces can become quite expensive, how have you managed the cost issues using ground covers and lower story plants to assist with the cost issues and also reduce weeds while establishing the upper story plants?

Eric: I think once you get to a certain scale the forest garden needs to pay for itself as a commercial enterprise. There are many products that can be raised in a semi-–shady understory that can generate revenue to meet and exceed the cost of establishing and maintaining them. In our garden we ended up starting a nursery which began largely by selling extra plants that were reproducing in our understory. Producing seed of native legumes, ground covers, and beneficial insect plants is one possibility. Cut flowers, berries, medicinal herbs, teas, and other products can generate revenue while providing the agroecosystem functions to boost productivity of trees and shrubs.

Short rotations of livestock again seem to be the easiest way to manage the understory of a large food forest. Pigs and goats can clear the land initially, grazers can “mow” the ground layer (as long as tree guards protect establishing trees), poultry can control insects, and pigs, if rotated through for brief periods when fruit and nuts drop, can pick up drops and break pest and disease life cycles.

In general the larger the area being managed, the more simple the understory needs to be. I’ve been researching the farm machinery used to establish prairies. These techniques are fairly well worked out and many native useful plants can be established from seed on the large-scale with these practices. Some people are even experimenting with controlled burns and fire-adapted food plants at a large scale.

 

GT: 3. Several of the suggested food plants used in Permaculture designs are on the invasive lists such as chinese yam, how have you used them in your designs to extract the positive qualities such as the food production while minimizing the unwanted qualities such as invasive growth?

Eric: I think we need to balance the potential benefits that a plant species can provide against the potential harm that it may cause. The all–native, non–edible garden has an ecological cost: if your food is coming from China or Brazil your ecological footprint is quite large. So I think we need to look at plants in the larger context of climate change and all of the aspects of the ecological crisis.

With that said, one of the guiding principles of permaculture is to begin with what is native. There are so many underutilized useful native plants, many of them are even difficult to get through the nursery trade. I think fans of both native plants and permaculture will agree that the non–native, non–functional landscape should be dramatically de-emphasized in this period of history. I also think we can all agree that useful natives from blueberries to buffalo gourds should be much more widely grown.

There are also some tricks that help to keep aggressive species under control. I grow sterile varieties of several potentially problematic non–natives. We use rhizome barriers, strategic harvesting, and pathway placement to keep species that spread aggressively by rhizomes in their place. Our hand–dug pond, with no outlet to native waterways, keeps aquatic species under control. Finally we have found that growing species in the sub–optimal conditions, like dry shade for wet sun–lovers, reduces their vigor dramatically and makes them easy to manage.

 

GT: 4. How do you describe Permaculture in two sentences or in a 30 second elevator speech?

Eric: Permaculture is a design strategy for meeting human needs while improving ecosystem health. It’s not about any particular practice (greenhouse, rainwater harvesting, tree crops, poultry), but rather about how to interconnect those elements to create a living, functioning ecosystem that humans participate in.

 

GT: 5. What five plants are a must have within your own yard?

Eric: American persimmon (Diospyros virginiana) is a delicious and underutilized native fruit. Sea kale (Crambe maritima) is a lovely perennial with honey–scented flowers, and its edible broccolis in May are essential components of our diet. Hog peanut (Amphicarpa bracteata) is a native nitrogen–fixing groundcover for shade. It has edible beans which are produced underground, though the difficulty of harvest makes them more of a novelty food than a staple. I love jostaberries (Ribes x culverwellii, a currant-gooseberry cross) for their tart fruit and ability to produce even in the shade of our neighbors’ Norway maples. We are also very excited this year about growing native lotus (Nelumbo lutea) in our pond for edible tubers and nuts (and stunning flowers).

Thank-you
I want to thank Eric for taking the time to answer our questions about permaculture and perennial edibles. His garden tours are so inspiring and informative. I look forward to Part II and more knowledge to use with my garden spaces.

(PART II)

-- - Debbie, SW Ontario Canada (USDA Hardiness Zone: 5a)