Can You Mix Cactus Soil with Potting Soil?

As a fellow plant lover, you want your plants to thrive. Thriving plants mean a greener, happier home. Cacti may be prickly, but they are an adorable addition to the home.

These low-maintenance plants have little qualms and grow well, even in the worst conditions. However, the soil means a lot regarding a cactus’s health.

Is it Okay to Mix Cactus Soil With Potting Soil?

Usually, cactus soil is made with everything in mind in advance. It is formulated to be perfect for all cacti.

However, there’s no such thing as a one-size-fits-all soil mix. There are so many considerations that the soil formulators can’t predict, like humidity, how much light you get, and the cactus variety you’re growing.

Adjusting the ready-made cactus soil you bought with potting soil is perfectly alright. However, you must know when it’s right to do that and when it’s uncalled for. To understand that, let’s wrap our heads around some information.

Cactus soil composition

Usually, cactus soil is composed of three things

Potting soil

Potting soil usually retains all the moisture and nutrients the plant needs. This is very rich soil that gives the plant the organic matter it needs.

In the cactus’s habitat, this soil is very dry but still is rich with nutrients and retains moisture from the infrequent rain or morning dew.

Sand

Sand makes it easy to improve drainage and makes the cactus roots feel at home. The sand makes the soil lighter and easier for the roots to push into. Sand also acts as something to dilute the potting soil.

Pumice or Vermiculite

Vermiculite, pumice stones, or gravel act to create air pockets in the soil. This is necessary to improve drainage. The excess water will slide down to the drainage hole sooner rather than later. For a potted cactus plant, drainage is critical.

How do we adjust Cactus Soil?

We adjust the store-bought cactus soil by increasing or decreasing these components according to our plant’s needs.

This is how we can make the cactus soil exactly as needed. Store-bought cactus soil would be half potting soil and half a mixture of two parts sand to one part gravel.

If we:

Add more Potting Soil:

By adding more potting soil, we are making the cactus soil richer in moisture and minerals. This may be incompatible in many cases.

Cacti are drought resistant and don’t mind days or even weeks of completely dry soil. However, they can not stand overly moist or wet soil.

However, there are some exceptions to this rule.

Special cactus variety

Some cactus varieties aren’t from harsher deserts or need more moisture. For example, you must water a Christmas cactus more often than an ordinary cactus.

When the cactus variety requires more moisture or more frequent watering, adding potting soil to the cactus mix is a good idea.

The resultant mix will hold moisture for longer, which means you will not have to water that frequently.

Summer Heat

Is the summer hitting your town in full force? When it’s too hot, small cacti pots dry out much more frequently, and it’s also the cactus’s growing season.

If your cactus lives in a tiny pot and you’re afraid of overwatering it, adding some potting mix is perfectly okay. This will help the soil not dry out too fast, so you won’t be tempted to water it more frequently.

Add more sand

If you add more sand, you are diluting the organic material in the potting soil. That means the soil will retain less moisture. This is the exact opposite of adding more potting soil to the cactus mix. You can do this if:

You live where it’s cold

Your cactus pot will dry slower if you live somewhere colder or where the sun shines less. That means the cactus roots will be seeped in wet soil for longer.

This situation is scary since it means the cactus roots are susceptible to rot. You can improve this situation by adding more sand to the soil. The sand will improve drainage and reduce the percentage of water retention in the soil.

Then you can rest assured the roots won’t rot.

Add More Gravel or Vermiculite.

If you add more gravel or vermiculite to the soil, that will improve the drainage of the cactus mix. You can do that if:

The Plant Pot is Very Large

Say you’re creating a cactus garden in a large pot. You will fill most of the available area with plants soon, but still, many small plants will be sitting in a pot much larger than they need.

In this case, the soil will retain water because of the size of the pot and the lack of deeply entrenched plant roots in the soil.

The plant roots can rot in this situation because water drains so slowly.

You can improve this by adding more pumice stones or vermiculite to the mixture. This will speed up the drainage, allowing you to build your cactus forest in peace.

Trial and Error

Now that you understand the principles of cactus soil, you can adjust it to your needs. However, if you aren’t a veteran indoor gardener, you might not be confident in changing the store-bought cactus mix.

We suggest experimenting with different compositions and seeing what works best for you. You learn the most through trial and error, so this is a great opportunity to further your indoor gardening knowledge and skills.

Control and Experiment

The best way to know what will work best is to grow cuttings of the same cactus in different soil mixtures. You can place one in the cactus soil without altering it. That will be the control cactus cutting.

Plant the other cuttings in pots with different percentages of added potting soil or other soil amendments you deem necessary. Over the course of some weeks, you will see which cactus is growing the best and how much you need to water it.

Cactus Plants (Mix of 6), Mammillaria Cactus Plants Live in Cactus Soil, Opuntia Cactus Live Plants, Cacti Plants, Cactus Décor Succulent, Cacti Décor Drought Tolerant Plants by Plants for Pets

Conclusion

Yes, you can add potting soil to any cactus mix as long as you know what you’re doing. It increases the moisture retention of the soil, so you must be careful!

You may also like: