The last couple of weeks I’ve discussed the wonders of organic matter in your soil and the mineral composition of the ground we work. Given the properties of the ground you have and how you can amend it with compost, let’s try and wrap up this complex topic of soil with basic management principles.
Below we’ll cover liming to correct pH, adding nutrients and guarding against pests in the soil.
Liming is a common practice in acidic soils in East Texas. At the simplest explanation, we apply ground-up limestone to neutralize (or raise the pH) on acidic soils. The ground-up lime typically takes weeks to months to change the soil chemistry. Lime isn’t really a nutrient, per se, although it will contain calcium.
Acidity in the soil limits the availability of nutrients. Your soil may have nutrients present, but if the ground is acidic (as it is often in East Texas) then the nutrients may be chemically tied up and unavailable for the plants to use.
We can add nutrients with organic or commercial fertilizers. There are 15 to 16 different nutrients that a plant needs to grow. Those needed the most are nitrogen (N), phosphorous (P) and potassium (K). Gardeners can buy them commercially in a concentrated form such as the old standby, 13-13-13. Or you can also get the same nutrients from a composted manure at the strength of 1-1-1.
While composted materials do have much more than the top three nutrients present, plants don’t care where they get their nutrition. It is the rate of different nutrients that plants care about.
Hay crops and lawn grasses want much more nitrogen to be green and leafy. Tomatoes and cucumbers want much more phosphorous than nitrogen to develop fruit. In fact, if you feed a tomato a high nitrogen fertilizer, you could end up with tall, leafy, dark-green tomato plants that have very few tomatoes.
Finally, with all the complexity and richness of soil, we should guard against pests that live there as well. Root-knot nematodes are common on sandy soils. While most every other kind of nematode is beneficial, the root-knot nematodes pierce their way into the roots and plug them up, causing severely stunted plants, even to the point of death.
Other pests in the soil could be insects and diseases. If we grow the same watermelons on the same ground year after year, those insects, fungal infections, viruses and bacteria that love watermelons will build in number and be ready to devastate the next crop.
The best solution is crop rotation. Farmers utilize this technique, or they go out of business. It’s true that some plants can be planted on the same ground continuously (purple hull peas for example), but many cannot. By rotating different crop species, you can break up the insect and disease cycles that cause so many problems.
The Angelina County Extension Office will have a seminar on “Building Your Soil” starting at 6:30 p.m. Monday. The office is at 2201 S. Medford Drive between Café Del Rio and the Farmers Market. There is no fee for the program.