Reducing the impact of drought
St. Louis suffered from the drought of 2012; in fact, the most recent U.S. Drought Monitor continues to show the metro area in moderate drought. As I mentioned in this post, we used an excessive amount of water last summer compared to the same period in previous years. Even in a normal year we typically have anywhere from three to six weeks of hot, dry weather sometime in the growing season during which I rely on municipal water supplies to sustain my vegetable garden. That’s fine as long as the municipal system can reliably deliver the water and we can afford to pay for it, but we cannot count on either continuing to occur every year. Last year the Missouri and Mississippi Rivers from which most of our municipal water is drawn had good flows from sufficient rains in the previous few years. This year, however, both rivers are at low levels, and there has been little snowfall so far this winter in their watersheds. Should we experience drought this summer, we might be faced with water restrictions. I’d rather design the garden to need less water and meet a higher percentage of its needs through the rainfall we do get. At the same time, 2008 had the highest yearly precipitation total and 2009 the fifth highest measured in St. Louis, so whatever I do needs to be resilient for possible above-normal rainfall as well as drought.
While I haven’t taken a permaculture design course, I have tried to design our yard according to my understanding of permaculture principles. A permacultural viewpoint suggests increasing our ability to catch and hold rainfall where my garden plants can access it. Increasing the organic matter content of soils, mulching, and designing swales to catch and soak in rain that hits the ground are all included in the permaculture toolkit. Since the biggest need for municipal water during drought periods is for the vegetable gardens, I am considering how I might do a better job in all three areas.
With regard to organic matter, some complications arise from sustainability requirements. I could add more organic matter to the gardens than I have been doing, but I’d have to import it from other locations. I’m trying to use only what compost and other organic material I can make or have on hand. If I rake more leaves from the front yard to make compost, those leaves won’t be mulching my front yard plantings and they might need watering in that case. I do, however, have a pile of plant stems from past years’ herb and flower gardens slowly decomposing elsewhere in the yard. I might try to make more compost from the pile materials for use in the vegetable gardens, as the herb and flower beds require very little if any irrigation. I have also sown some of the vegetable beds to crimson clover for the winter, which should hold more nutrients in the soil (and hold the soil during windy periods). The clover can be dug in or composted before planting the next crop to increase organic matter content. In 2013 I plan to try interplanting each bed with crimson clover seed to further increase nutrient cycling, reduce weeds, and increase organic matter content over time. However, I will have to watch in case the interplanting increases water needs in summer; if so, I’ll remove the clover and compost it, then return the compost to the soil later on.
As for mulching, I use mulches (wood chips, autumn leaves, and/or a living mulch of violets and other groundcover plants) on the herb and flower gardens, but mulching doesn’t work in my more traditionally managed vegetable garden, which I cultivate with a broadfork or shovel and weed with a hoe. The crimson clover interplant may, however, act as a living mulch if I can plant it at the right density. Permaculturists look askance at digging for its disruption of the soil’s mycelial network, but a traditional vegetable garden in full sun might be best viewed as a disturbed meadow which is prevented from succeeding to forest by further disturbance. In this case a mycelial network does not form. However, if I can get a crimson clover living mulch established in the vegetable garden, I might be able to reduce or eliminate digging and weeding and also increase the capacity of the soil to hold water.
While I have been collecting information on designing and digging swales, so far I have not put this information to practical use. I will be looking more closely at the situation this year.
A different approach to decreasing irrigation needs is to increase spacing of the plants in the vegetable beds to be more compatible with available rainfall. While Ecology Action claims that closely-planted beds actually require less water on a square foot basis than traditional row-based spacings and that small amount of water can be supplied through irrigation in many cases, Steve Solomon claims that it is better to space plants much more widely if one is relying on (possibly insufficient) rainfall. The wider spacings mean each plant will not be competing for others and will thus yield more food than the same number of plants grown at closer spacing. A compromise position, one that Steve himself suggests, is to start with the closer spacing but then remove enough plants to create the wide spacings he recommends if rainfall proves to be insufficient and irrigation is not available. This approach makes sense to me. I should have done it last year, but I could not bring myself to rip out plants after I’d put so much effort into them and since we were not under water restrictions. This year I will do it if we get hit with water restrictions, and I will consider doing it if the Drought Monitor shows us at severe or worse drought and the weather patterns suggest that insufficient rainfall is expected to break that drought for a few weeks or more. If I am in the mood for a real scientific experiment, I can increase spacing for a portion of one of my crops and keep separate records of yields for that portion compared to the normal spacing, watering them (or not watering them) the same amount.
Last month our new tool shed, shown in the photo at the beginning of this post, was installed where a dying silver maple tree had been removed last spring. With the tree gone, the vegetable gardens receive more afternoon sunlight and suffer less competition for nutrients with the maple roots. The tool shed is located closer to the gardens than the garage and the basement and has enough room to hold all the garden tools and supplies that used to be scattered across those two locations. A further benefit is that the tool shed is located at the highest point of the yard. This year we will add gutters and downspouts to the shed roof and direct the rainwater from the roof into a 500 gallon plastic tank. From there we can gravity-feed collected rainwater onto the gardens when needed and direct overflow to mulched garden paths or, if I get swales dug in time, to the swales for infiltration into the soil. The stored rainwater should replace a portion of the municipal water we’d otherwise use for irrigation.
Reducing use of electricity and natural gas
Mike and I cook on an electric stove, cool with a central air conditioner or electric fans, obtain winter heat from a forced-air natural gas furnace that requires electricity to operate the thermostat and the igniter and to power the blower, heat water with natural gas, keep foods cool with an electric refrigerator, and wash clothes with an electric washing machine. Through means such as setting the thermostat to 60F most of the time in winter and 82F for air conditioning, setting the water heater to 125F, insulating the hot water pipes and adding insulation to the walls, attic floor, and basement ceiling, sealing air leaks, and replacing inefficient old appliances with very energy efficient versions, we have reduced natural gas consumption by about three-quarters and electricity consumption by about 40% compared to what we used for a comparably sized house in 1990. However, we’d like to reduce consumption of each further and to be prepared to do without each for periods of time. Our biggest vulnerability is winter heating; our only backup source of heat at this time is a small kerosene heater. We use heat most days from November through March. While we use air conditioning for many fewer days than heating, it accounts for a considerable fraction of our total electricity use and cooking accounts for some of the remainder, so we need to work on these as well.
Our house was built in 1928, when coal-fired furnaces were very popular in our area. Our house has a round platform on the basement floor that supported a coal furnace and an opening in the basement wall through which coal was loaded into the basement. Coal furnaces typically burned hot; I’ve heard most people with coal furnaces kept at least one window partially opened in winter to balance the heat from the furnace. With that kind of heat fireplaces weren’t needed, and our house has none, so we do not have an easy way to add a source of wood heating. The chimney is on the east wall of the house outside of the kitchen and has a double flue. One flue would have been used for the coal furnace. We believe the other was used for a coal or wood stove in the kitchen for cooking; the chimney’s location and double flue suggest this possibility. St. Louis regulated the burning of high-volatiles coal in 1940 to reduce its smog problem; as a result households gradually switched to natural gas, oil, or electric furnaces and cooking stoves. The previous owner told us the house had an oil furnace when she and her husband purchased it in the early 1960s, but she’d replaced it with a natural gas furnace in the 1970s when oil prices rose drastically. We replaced that furnace with a 94% efficient unit that vents into a pipe through the wall. The natural gas service was not extended to the kitchen, so we cook on the electric stove that came with the house. The house had an electric water heater in the basement when we bought it. We’ve since replaced it with a natural gas water heater that vents through an insert in one of the two chimney flues. Nothing vents through the other flue at present.
For short term electricity outages we can cook on a camp stove and a fire pit, bake with a solar oven, and use flashlights, oil lamps, and a solar lantern for lighting. When we are not using heat we do not find going without electric service to be a burden, especially if we have some ice available so we can hold refrigerated foods in coolers (in the winter we can keep foods cool in our cold storage area). However, lack of electric service in the winter means no heat. For a few days we could use the kerosene heater, but that is a short-term solution at best. If we had a wood-burning stove that we could heat and cook on, we could better handle short duration electric outages and, as we accumulated a supply of wood, gradually reduce use of fossil fuels for heating and cooking. I wouldn’t want to cook inside on a wood-burning stove during the summer, but if we had a summer kitchen set up in a shady location, we could shift some of our summer cooking outside, reducing excess heat in the house.
For 2013 we will concentrate on providing ourselves with a shady sitting area that can double as a summer kitchen. We already have a patio on the east side of the house with a structure on which we can suspend a tarpaulin to provide shade. However, the cheap plastic tarps we’ve used in the past don’t last more than one summer. This year we’ll purchase a canvas tarp that should prove to be more durable. We’d also like to add an awning extending out from the north wall of the house to cover a larger area that would eventually become the main area for summer cooking and other activities. I am planning to build a small rocket stove to see how it works compared to the Weber kettle and hibachi that we already have for summer cooking. I’ll keep you posted as the summer sitting area and kitchen develops! I don’t want to consider replacing the electric stove with a wood heating and cooking stove until we have a summer kitchen set up that we actually use, so this will be the focus of our efforts in 2013.
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