The Benefits of Hillside Farming
Katie Spring owns and operates Good Heart Farmstead with her husband Edge Fuentes in Worcester, VT.
Prime agricultural soils are often found in flood-plain, where the land is nutrient-rich and fertile. Hillsides, in contrast, can bring a range of challenges for the farmer: nutrient-poor soil, erosion, and nutrient run-off to name a few. But as we experience more extreme weather in the Northeast and all over the country, hillsides can offer some unique solutions to environmental pressures.
Hillsides: The Underutilized Resource
As young beginning farmers, we didn’t expect to buy land with the perfect agricultural soils, and we knew early on that we’d spend years building soil and increasing organic matter in our fields. We had met on a hillside farm in Alaska that grew 3 acres of veggies on terraced land, and so we were excited to find land with a slope and to integrate some of the practices we had learned at Calypso Farm.
Though it requires more work to establish cropland on a hillside, the benefits, from flood protection and gravity-fed irrigation to the increased solar gain on south and south-western slopes, make the work worth it. The solar gain difference is particularly significant—according to Eliot Coleman’s book The New Organic Grower, “Land in the northern hemisphere at a latitude of 43 degrees with a slope angle of 5% to the south with have the same solar climate as the area 300 miles to the south of it.”
Watch & Learn
Before tilling up an acre for crops, we watched the land through a spring and summer. We took into account where the natural high and low points are, where the water naturally flows and, judging by the types of plant species growing, where the nutrients seemed to be the highest (which coincided with the water flowed). We chose a central spot high on our field that had a small crest in the center that falls away to the south, out of the way of the water flow. Our land has a gentle enough slope to avoid leveling and building terraces; instead, after tilling, we used broadforks and a pick to make raised beds that follow the contour of the land. Rather than tilling the entire field each year, we will have permanent beds and use a low-till system to encourage the build up of soil life.
Gravity-Fed Irrigation & Drainage
Our first season started off with a hot and dry May followed by a cool, rainy
June. In May, we set up a 250-gallon water tank at the top of our field and used the brook above to gravity-fill it. We then set up drip tape and gravity-fed water through the garden. We’d fill the tank as we irrigated to keep the water supply going, and this system kept the plants happy until June came and we no longer needed it.
In the drenching rain day after day, the raised beds held their shape as the broadforked soil was able to absorb much of the water, while excess water ran off our crops into the field. Thanks to our slope, we were able to continue transplanting and harvesting when fields in the lowlands were bogged down with water. During this time, we diverted the water in the holding tank from the garden and used it instead to bring water to our livestock in the pasture below.
Hillside Challenges & Mitigation
Of course, we had our challenges, too. Even though the garden drained well, there were still days too wet to work in it, and parts of our pasture were flowing with water, forcing us to keep our sheep out of those areas which also happened to have some of the nicest grass. A little ditching helped relieve the problem somewhat, but keyline plowing or a series of irrigation ponds may offer a more permanent solution.
It is important to note that the techniques you should use depend greatly on the subsoil characteristics and annual rainfall in your area. In Papua New Guinea, for example, where hillsides up to 45 degrees are farmed and rainfall can exceed 150 inches a year, down-slope oriented beds are actually preferable. This is because the clay subsoil does not erode easily, and the water is able to drain away. If cross-slope beds were used, the clay-lined beds would hold huge pools of water, which would eventually overflow, carrying the whole bed down with it.
In drier regions, it is usually preferable to site beds across the slope on the contour. A subsoil keyline plough, which does not invert the soil but creates channels through it, is an excellent tool for encouraging water to move across the land and soak into it rather than flowing downhill.
Let the Land Work for You
Even with our challenges, the slope of our land more often offers advantages. In heavy rains we are protected from floods, in dry times we can use gravity to our advantage in irrigation, when frost settles in the valley come fall we can stretch out an extra week or so before the frost makes its way uphill, and the Southwest orientation magnifies the sun’s effect, warming our fields from spring through fall. And let’s not forget the many cultures and people who have farmed on hillsides long before us—from Asia to South America, hillside farming has been utilized for centuries as an effective method of farming on seemingly unlikely farmland.