GET THE DIRT ON CACTUS CARE: SOIL RECIPE & POTTING TIPS
Cactus Care: choosing the Right Soil Mix and Fertiliser for optimal Growth
Do you have a cactus that just won't seem to thrive, no matter how much you water it (or don't)? It could be because you're using the wrong soil mix. Don't worry, we won't tell your cactus that you've been using regular old dirt this whole time.
Most cacti are happy living in native soil in Australia, especially along the coastline where things are nice and sandy (no clay to be found). But some cacti can be a bit picky when it comes to what they're planted in. That's why it's good practice to use a soil mix specifically designed for fast drainage. You can find these premade mixes at most garden centers, but let's be real, homemade is always better. Plus, your cactus will probably thank you for the extra love and attention if you make your soil mix yourself!
Now, we're not saying you have to make your own soil mix. We're just saying that if you do, your cactus might be a little bit happier (and healthier). And if you prefer the store-bought stuff, that's cool too. Just make sure to read this post for tips on how to properly prepare your pots before planting.
Here's our go-to recipe
cactus soil mix:
Ingredients:
• 1 part vermiculite (for added drainage and aeration)
• 1 part coconut coir (for moisture retention and nutrient supply)
• 1 part pumice (for added drainage and a lightweight feel, and because it sounds
fancy)
• 1 part coarse sand (for even more drainage)
• 1 part potting soil (for a little bit of everything)
• Cactus fertiliser (follow the instructions on the fertiliser package for the
appropriate amount to use)
• OPTIONAL ADDITION: Worm castings
DIRECTIONS
1. Mix all of the ingredients together in a large container, Make sure to get everything
well combined. Be safe when mixing soil, slightly wet ingredients to minimise risk of
inhalation and pretty please, wear a mask.
2. Use the soil mix to pot your cactus plants, making sure to choose a pot that allows
enough room for the plant's roots to spread out. Prepare your pot with flyscreen over
the drainage hole and a light layer of scoria before the soil.
Hot tip: Google the name of your plant to find out if your species prefers a dish or
shallow pot.
3. Give your cactus a VERY light mist after planting, but then let it air dry
before watering again. Cactus plants don't like to be soggy, so make sure the soil
dries out fully between watering.
4. Fertilise the plant according to the instructions on the fertiliser package. Cactus
plants don't need a lot of fertiliser, so don't go crazy with it. Fertilise in spring, annually, or biannually.
Note: If you are having trouble finding some of these ingredients, you can try substituting them with other materials. For example, you can use crushed lava rock or expanded shale in place of pumice. Just be sure to use well-draining materials that won't hold onto excess moisture.
Well-draining soil mix:
Use a pot with drainage holes. Cactus plants are prone to root rot if their roots are left sitting in water, so it's important to use a soil mix that drains well. To improve drainage, you can also add a 2cm layer of drainage material, such as pebbles or small rocks, to the bottom of your pot or container. This 2cm depth of drainage material will ensure the water table remains low. Cactus Vision also uses fly-screen cut into a square to cover the drainage holes, to safeguard against the drainage hole getting blocked. Correct pot preparation will help excess water drain away from the roots and prevent the soil from becoming too saturated.
Fertiliser:
Cactus plants are not heavy feeders and do not require a lot of fertiliser. In fact, too much of the wrong types of fertiliser can actually harm cactus plants. Use a balanced fertiliser with a low nitrogen NPK ratio, we recommend a 5-10-10 formula, and fertilise once or twice during the growing season (the start of Spring and just before Autumn). You can also try adding worm castings to your soil mix to provide a boost of natural nutrients. Just don't overdo it – a little bit goes a long way when it comes to fertilising cactus plants. Hot tip: Google the name of your plant to find out if your species is one of the few who ONLY prefers fertilisers once a year, outside of summer.
Repotting:
Repotting your cactus plants every 5 years or so can help ensure optimal growth and prevent overcrowding. However, it's important to note that keeping your cactus plants in their pots indefinitely won't typically hurt the plant, it may just stunt its growth. Use your best judgment and consider the size of the pot, the size of the plant, and the overall health of the plant when deciding whether or not to repot. A good sign to check for is discoloration, if your plant is looking pale or sunburnt, it may need a larger home.
Acclimation:
If you're introducing your cactus to a new environment, it's important to acclimate it gradually. This means gradually introducing it to its new light, temperature, and humidity levels, rather than throwing it into a completely different environment all at once. This will help prevent shock and ensure that your cactus has a smooth transition to its new home.
Best time to plant:
In Australia, the best time to plant cacti is during early spring or summer months, when the weather is warm and the soil is dry. This will give your cactus plenty of time to establish itself before the cooler winter months arrive.