Test Soil to Find Its pH Value
The soil reaction, or measure of acidity or alkalinity, is based on a scale of 1 to 14 and is referred to as pH. A pH of 7.0 is neutral. Any values below 7.0 are acid, and any values above 7.0 are alkaline.
The ideal pH values for vegetable garden soils are 6.0 to 6.5. Vegetable plants do not grow well in acid soils with a pH of 4.5 to 5.5 or in alkaline soils with a pH above 7.5. Soil testing is the only way to know the pH of your garden soil. Contact your county Extension office for a container and instructions for taking a soil sample. There is a $8 fee for a complete analysis (pH plus nutrient analysis with lime and fertilizer recommendations) on each sample. The lime recommendation is the single most important piece of information on a soil test report.
In areas with high rainfall like Mississippi, soils are generally acid. However, there are exceptions (particularly in the Delta and Blackland Prairie) that prove the need for soil testing. Of the garden soils analyzed at Mississippi State University’s Soil Testing Laboratory from 1999 to 2004, 49 percent had a pH of 5.9 or below and needed lime. Twenty-six percent were in the range of 6.0 to 7.0.
The pH of the soil tells you if the soil needs lime. Where it is needed, limestone is the most effective and inexpensive aid available for soil improvement. The soil’s calcium and magnesium levels tell you what form of limestone—dolomitic (magnesium and calcium) or calcitic (calcium)—to apply. An acid soil that tested medium low to very low in magnesium should be limed with dolomitic (high magnesium) lime. An acid soil high in magnesium can be limed with either calcitic limestone or dolomitic limestone.
Acid soil results in poor plant growth, partly because of poor root growth. This means greater susceptibility to drought stress and less efficient use of soil nutrients. Plants growing in acid soil may show deficiency symptoms of several plant nutrients.
Apply lime well ahead of planting (2 to 3 months) to provide time for it to dissolve and change the soil pH. However, limestone begins to react as soon as it is incorporated and can be applied at any time to increase soil pH levels. Apply lime evenly over the entire area and work it into the top 4 or 5 inches of soil. Incomplete mixing may make future tests show a need for more lime, which can result in overliming and poor plant growth. Limestone not only raises the soil pH but improves fertility. Lime also improves the structure of clay soils and makes them easier to work.
Liming is not a once-in-a-lifetime event. Since soils limed to the proper pH return to their acid state with time, soil test every three years to determine if additional lime is needed. Sandy soils become acid again faster than clay soils.
Factors causing the soil pH to drop are listed below:
- Using acid-forming fertilizers.
- Leaching of lime from the soil by rain and irrigation water.
- Decomposing of organic matter and release of organic acids.
Autumn is officially here! It’s not hard to love this time of year. Temperatures are cooling, leaves are changing, and there will be more branches than foliage soon. It’s hard not to love this time of year! As we close out this calendar year, it’s easy to convince yourself there’s not much to do in the yard. Take a break, but also take time to check off these tasks
The 2021 Fall Flower & Garden Fest will return to an in-person event but will be modified because of the persistently high number of COVID-19 cases. The fest will be held 9 a.m. to noon daily Oct. 4-8 at the Mississippi State University Truck Crops Branch Experiment Station in Crystal Springs.
With the fall season slowly creeping in, there are many things to look forward to, including the drop in temperature. I enjoy watching the leaves change color and drop, too. That also means now is a great time to pull out your rakes, garbage bags, and compost bins and prepare to remove the leaves in your yard! Here are a few other things for you to accomplish in your garden and landscape during the month of September.
When members of the Jackson chapter of Alpha Kappa Alpha sorority brainstormed ways to serve their community, they decided to start a gardening project. Their plan was twofold: grow fresh produce for members of the community who could not get to the grocery store on a regular basis; and get community members involved and teach them how to grow produce. But they soon discovered they were going to need some guidance.
After a relatively mild summer, heat and humidity have arrived in full force in Mississippi. Going outside during the afternoon is miserable these days! If you’re like me, I try to get all my outdoor activities wrapped up in the morning or late afternoon to avoid the heat. Be sure you can recognize the signs of heat-related illness, and remember to drink plenty of water anytime you’re outside! Hydration is important!