What's the best soil mix for healthy cactus growth?

The right soil mixture is essential for cacti to be able to survive and grow permanently. Typical potting soil holds too much moisture, which can cause root rot and eventually kill the cactus. I learned that the hard way when I lost my first prickly pear due to poor potting soil. The gritty mix will allow roots to breathe while mimicking desert conditions, with just enough nutrients to keep the plant healthy.

Coarse sand is a necessity in cactus soil. Coarse sand should constitute one assemblage of cactus soil, accounting for approximately 40% of the total weight, as well as providing drainage. Horticultural sand that contains 1-3mm sand particles will be the best option; refrain from using fine beach sand, as it tends to compact. Since I've transitioned to sand that is properly graded, I've seen better and healthier root development in my plants.

There are easy ways to mix your soil. Mixing dry ingredients thoroughly first, then adding the least amount of water, is the best approach. A simple way to check the drainage capabilities of your ingredients is to saturate a sample pot and note the time it takes for the water to drain. Ideally, you want to find a mix that drains completely within 30 seconds. Store any unused soil in an airtight, zipped container to preserve the structure of the soil mix.

The success of your plant re-potting relies on good soil preparation. It is important to change the old soil every 2 to 3 years after it has accumulated minerals. It is best to water your plants 2 days before repotting to help reduce root damage. My oldest barrel cactus has been in the same custom mix for 8 years now and is growing steadily.

Read the full article: 7 Essential Tips: How to Care for Cactus