What Kind of Topsoil Is for Cactus?

Well-Draining Soil

• Well-draining soil consists of silt, sand and clay. When soil has too much clay, it cannot adequate drain properly. To check if your topsoil consists of clay, grab a handful and squeeze. Soil that releases water droplets means that you have clay topsoil. Soil that breaks apart is sand. If the soil is malleable, you have loam. Gardeners must amend their clay topsoil and plant their cactus using a soil mixture that promotes drainage.

Mixing Your Own Soil

• Create a hole in the garden that is twice the size of the root ball and at least 6 inches deep. Mix your own potting soil for backfill. Good cactus potting soils consist of 1 part builder's sand, 1 part peat moss and 1 part garden soil, according to the University of Rhode Island. Use sterilized potting soil if your garden has a history of soil fungal diseases or root rot.

Planting in the Yard

• Place the cactus in the hole no deeper than it was in its original container. Add soil at the bottom of the hole if necessary to attain the proper planting depth. Avoid packing the soil above the base of the plant, which encourages stem rot. Pat the soil around the base of the plant by hand. Refrain from watering the plant so that it can acclimate in the soil.

Mulching

• Spread a 1-inch layer of gravel around the base of the cactus plant to help prevent fungal spores that cause diseases such as stem rot. Check the gravel periodically to make sure weeds are not growing from the crevices. Gardeners can place a large rock next to their cactus plant for shade and to protect against sunburn during the summer. The rock also traps heat during the winter, according to Texas A&M University.