It may be March when you read this. Unless we receive significant snow or rain this spring our soil will be very dry. It is time to think about ways to make our water stretch farther. If you are still watering with an air-born system, like a sprinkler, it is time to change to a system that uses less water and puts it in the soil instead of evaporating in the air.
Pick a nice day in March, dig around in the soil a little and see how dry the soil is. Check some areas in full sun without leaf or ground cover and compare with some of your soil that has leaf or bark cover. In March it is below freezing most nights and too cold to turn on drip systems. You should either hand spray or use a sprinkler to water trees, bushes, grass, and other perennial plants. When the soil is “bone” dry, you may notice water running off. Normally, soil has chemical charges that attract water to it. When the soil is too dry, there is a change in the soil and water is repelled. I notice this mostly in early spring after a very dry winter. It is most disconcerting seeing water run off soil that is obviously dry. It takes effort to rehydrate that soil, but it can be done.
Let’s look at the soil. In New Mexico some people have sandy soil, while someone living a short distance away has clay soil. If your soil is gritty, you have sand. You have clay when you wet your soil and you can make a pot out it. Another component of soil is silt. This is a particle size in between sand and clay and feels like pie crust dough when damp. Great soil is a combination of all three components plus organic matter.
If you would like a better idea of what kind of soil you have, do a jar test. Get a quart jar with a lid. Go outside to a section of your yard that you haven’t gardened. Clear away debris and anything not soil. Dig down 1-2 inches and fill the jar halfway with soil. Top it off with water. Shake thoroughly and allow the soil to completely settle. This may take 1-2 days. Look carefully at the layers of different soil particles. At the bottom is heavy sand and small rocks, next is silt, and at the top are small particles that are clay. The thickest layer is the type of soil that your soil is made of: sand, silt, or clay.
Sandy soil is easy to dig, and plants grow well in it but water drains out, so it dries out fast. Clay soils are made up of very fine particles, so air and water do not move easily through the soil. It holds water so tightly that all of the air pockets are filled and plants die from lack of oxygen. When it dries out the fine particles stick together like glue and the soil cracks, exposing plant roots to dry air.
Southwestern desert soils are very distinct because they were formed under dry conditions. Dry, hot environments are not conducive to the build-up of organic matter in the soil. Whatever your soil is, in New Mexico you are going to need to add organic matter.
Moist environments favor the growth of plants. As plants die and decompose, they add organic matter to the soil. Organic matter is anything that was living at one time: leaves, grass, compost, peat moss, manures, coconut fiber, are all good products to mix into the soil. Organic matter mixes with the bacteria, fungi, earthworms, and insects to enrich the soil.
Leaves and grasses decompose and enrich the soils in wet areas every year. We need to copy that process and add organic matter to the garden yearly. There are many ways to add organic matter to soil but they all involve mixing it by hand or roto tilling and watering.
More about starting a garden, soil, and compost next Month… If you are new to gardening in New Mexico, an excellent source of information is the Down to Earth, A Gardener’s Guide from the Albuquerque Area Extension Master Gardeners. It is available at the Albuquerque Garden Center, 10120 Lomas Blvd NE, MF 9:30-2:30 pm and in their website. I bought it when I first moved to New Mexico and it is the first place I look for gardening information.
Edith Iwan is a Cibola-McKinley County Master Gardener who lives and works in Thoreau. As a Master Gardener she assists the County Cooperative Extension Service in providing accurate, research-based gardening information to county residents. If you have any gardening questions, please call the NMSU Cibola County Extension at 505-287-9266 or NMSU McKinley County Extension at 505-863-3432