Food Needs & Yieldsand Micro-Climate

Hilary EmmonsIntegrated Backyard Homesteading - Winter 2017

1. Food self-sufficiency: summaryWe’re a 2-person household; we like to entertain and have frequent guests. We eat mostly vegetarian - lots of veggies, fruits, grains, legumes and eggs (some fish, pork or beef 3-4 times a year at home).

Since we’re growing in a small space, I calculated using biointensive methods (at the low end of the scale, assuming there would be a learning curve for the first few years).

When selecting my top-consumed items, I focused on fruits and vegetables that can be grown in my region. I included rice as one of our grains since it’s a big part of our diet.

What stood out to me most is the amount of food we consume that we have no practical way to grow on-site due to size, climate and legal constraints: tropical fruits; sugar; rice, cheese and butter. Becoming truly self-sufficient would require a big change in our diets, a lot of bartering, or both.

Crop Servings/year Pounds/year # of 100 sq. ft. beds

Spinach 800 (600 fresh, 200 cooked)

107 3

Onions 300 15 .15

Garlic 600 4.5 .075

Tomatoes 500 (fresh) 218 2.15

Potatoes (Irish) 400 143 1.5

Squash (winter) 300 120 2.5

Broccoli 200 65 2.5

Carrots 100 36 .36

Cucumbers 100 23 .15

Beets 50 18 .3

Crop Servings/year Pounds/year # of 100 sq. ft. beds

Wheat 2,500 (bread/tortillas/pasta) 156 40

Rice 1,500 63 8

Oats 1,000 42 14

Black beans 624 40 10

Lentils 416 30 7.5

Chickpeas 416 36 9

Apples 416 148 3

Blueberries (used blackberry) 100 25 1

Pears 100 30 1

Grapes 50 25 .5

Peaches (clingstone) 50 15 .25

4. Micro-Climate MapThis map is based on summer sun patterns - the north of the site becomes a part-shade area in the winter due to the lack of tree leaf cover, while the east of the property receives only about 5 hours/day due to the later sunrise (Bane, “Finding the Sun,” 138-139).

It’s clear from this exercise that there is very limited full sun for vegetable production, which will present significant challenges for self-sufficiency.

A larger version of this map, along with an an overlay on the base layer, is attached to the post.

5. Micro-Climate: the right crop in the right placeDue to limited sun access, I focused first on what was possible in full shade and worked my way up. Crops that can tolerate shade don’t necessarily thrive in it, so yields would be lower.

Full shade (but at least 3 - 4 hours of sun):

Spinach and other greens ~ Beans

Full sun: Garlic ~ Tomatoes ~ Squash ~ Cucumbers ~ Wheat ~ Rice

~ Oats ~ Lentils ~ Apples ~ Pears

Part shade: Beets ~ Carrots ~ Potatoes ~ Broccoli ~ Onions* ~

Chickpeas ~ Blueberries** ~ Peaches

*Onions like cooler moister soil - take advantage of areas that stay wet

**Blueberries do well in morning sun - could plant along east side of house

Brick house exterior creates a warm micro-climate - spring and fall crops could increase overall yield

There’s more room for cool season crops when leaves have fallen, transforming some “full shade” areas into “part shade.”

6. Needs and Yields ConclusionsWe live in what Peter Bane characterizes as a Tiny City Lot of less than ¼ acre (Bane, p. 111). The small size, combined with the amount of shade the property receives, means that complete self-sufficiency is likely an unrealistic expectation for us.

Based on the calculations from “A Plan for Food Self-Sufficiency” by Cindy Connor, we’d need almost 11,000 square feet (about .25 acres), to grow our top crops - that’s a tiny fraction of the US average of 3 acres per person used for food production (Bane, p. 107), but it doesn’t cover all of our consumption which also includes eggs, dairy, fish, some meat, and non-native produce. By comparison, our site has only a small, approximately 300 square foot area that receives full sun.

We’ll need to prioritize what is most important to grow ourselves that fits within the constraints of our site, and we’ll also need to be adaptable and creative in selecting, and making use of, crops that can thrive in other micro-climatic conditions.

ResourcesThe Permaculture Handbook, Peter Bane and David Holmgren. New Society Publishers, 2012

“A Plan for Food Self-Sufficiency,” by Cindy Conner

http://www.motherearthnews.com/organic-gardening/shade-tolerant-vegetables-zm0z11zsto

http://www.smallfootprintfamily.com/28-vegetables-that-grow-in-partial-shade

http://www.harvesttotable.com/2012/04/vegetables-for-growing-in-shade/

http://www.harvesttotable.com/2009/04/how_to_grow_chickpeas_garbanzo/