Clay soil is clumpy, sticky and has little aeration for a healthy garden. Its dense structure leads to poor drainage, which is frustrating for gardeners. However, it's possible to improve clay soil with the addition of gypsum. An inexpensive solution, gypsum penetrates the clay and improves its basic structure.
What is Clay Soil?
Clay soil has a high clay and silt content, and low organic humus content. Humus is aerated, and clay is clumpy and compact. To improve the texture, loosen the soil in order to allow air to go between the particles.
Why Add Gypsum to Clay Soil?
Gypsum works by penetrating between the clay particles to break up the soil structure and improve the aeration of the soil. It is a mineral compound comprised of calcium and sulfur, and can often be found near limestone. Adding gypsum to your clay soil is an inexpensive solution to improving its texture and quality. Gypsum is not high in nutrition, but it is still suitable to alter the soil structure. Gypsum is also PH neutral, so will not change the acidity or alkaline levels of the soil.
How Much Gypsum To Add to Clay Soil?
The recommended amount of gypsum to add to clay soil varies quite widely from gardening experts around the globe. This is because the right amount for your garden will depend on your region and particular type of clay soil. For best results, consult with your local nursery.
A typical recommendation for an existing flower bed is 40 pounds of gypsum to every 1000 square feet of soil. For a new bed, this recommended ratio increases to about 40 pounds for every 500 square feet.
Add Gypsum to Your Soil
Some gardeners advise that spreading a layer of gypsum over your lawn should do the trick. However, others caution that simply spreading a top layer of gypsum is not enough, and that gypsum needs to be mixed into the soil in order to work. In fact, gypsum will work itself into the soil over time, as it is a chemical compound that will be drawn into the soil. However, to get your gypsum working faster, digging it into the soil will certainly speed up the process. Either way, you will also need to replenish the gypsum a couple times a year. Remember, gypsum won't work miracles overnight. It will take time to truly alter the structure of your soil.
