Have you had trouble growing aloe vera and really want it to work so you can harvest the leaves and make a skin lotion? After all, if it’s good enough for Cleopatra… These plants are useful for many reasons for body and skin problems.
They also make good houseplants in the right setting, so anyone can grow one. The trouble is that sometimes they don’t perform as well as they should, and the answer is in the soil.
The Short Answer
The important part of the plant Aloe vera is the ‘aloe’. This will give us some clues as to how to treat them and what kind of soil they prefer. As a succulent plant hailing from the hot and dry regions of Africa, Asia, Europe, and the Americas, it is, in its natural habitat, grown in sandy soil with minimum water. So, the short answer is sandy soil.
The Long Answer
Everyone seems to have their own unique soil mix recipe for succulents and aloe.
If you ask succulent and aloe growers what soils they recommend, you will find that everyone has a different recipe for their soil mix. They can all agree that it should be well-draining and, when in doubt, use a commercially available substrate specially formulated for cacti and succulents.
Never use soil from the garden. Once you know what each part of a potting mix does, it will be easier to make your own.
The Basic Recipe
Play around with varying material ratios to tailor your soil mix to your specific location.
Experiment with different ratios of materials to find the best one for your area. The climate, fluctuations in temperature, and humidity will all affect your soil, but you can start with the basic recipe as follows:
- 1 part porous material like perlite, pumice, or Akadama
- 2 parts drainage materials such as coarse sand or grit
- 2 parts organic materials such as potting soil (with compost added)
Mix all these ingredients well together before using them in containers.
General potting soil mixes retain moisture for plants. This is a good thing for most plants but not for an aloe like aloe vera or any succulent. Provide quick-draining soil to avoid water-logging the roots. This will be detrimental to their health and may cause root rot and even death. There are various ways to include porous materials into the mix, some with other super benefits. Choose any of these for your mix.
This component possesses a porous structure that retains some water while facilitating drainage.
What you might think are polystyrene balls in the soil mix you find at the nursery is, in fact, a volcanic rock that has been expanded using extremely high heat, becoming very lightweight and useful as a horticultural substrate. In its natural environment, perlite is an amorphous black or grey glass with a substantial list of beneficial plant nutrients, including potassium, iron, manganese, and calcium.
The perlite is mined and then processed to produce the light material in a process nicknamed ‘volcanic popcorn’ making. The water content in perlite will make it pop at very high temperatures of around 1650°F. Once popped, the perlite is up to 16 times bigger and significantly lighter.
The benefits of adding perlite to a soil mix are that it is stable (unlike polystyrene, which can be squashed), has a neutral pH level, is still able to retain some water in its porous structure but allows water to drain away, and helps aerate the soil so the roots can ‘breathe.’ It also helps improve drainage, which is essential for succulent and aloe soil mixes.
Pumice is abundant in valuable trace elements and is obtained by crushing lava rocks.
Very similar to perlite, pumice is a mined mineral created by crushing lava rocks, and it is full of beneficial trace elements. It is lightweight and has tiny craters on its surface that hold air, water, and nutrients in the soil while assisting with drainage and releasing water when necessary.
Pumice is naturally lightweight and has been caused by the reaction of lava with high water content, causing gases to expand and the lava to bubble and fizz. Once cooled, the rock contains the tiny air bubbles that give it porous properties.
Of particular interest is the fact that pumice contains up to 70 beneficial trace elements that can assist with keeping your aloe healthy.
One distinctive feature of Akadama is its color transformation when moist.
Mined in Japan, Akadama is another volcanic rock substrate that has been used for growing bonsai for many years. It’s used for its properties, which include water retention and nutrients, as well as being a porous material that assists in drainage and aeration.
What is special about Akadama is the color change it has when wet. The darker color indicates high water content; as it gets lighter, the plants require water. It’s like its own water sensor. In recent years, it has become popularized for use in growing succulents and cacti.
Sand must be included to mimic the soil of the hot and dry regions from which aloe vera originates.
Sand, Gravel, and Grit
A well-balanced aloe mix relies on multiple particle sizes for optimal plant health.
Making up the bulk of a good aloe mix is sand of different sizes, which helps trap air in pockets and allow the roots to get much-needed aeration. Large gravel particles are good for a layer at the bottom of the pot to help prevent soil from escaping through the drainage holes, and smaller sand particles throughout the mix will help with drainage along with the characteristics of the porous material discussed above.
Potting Soil and Compost
Enhance the soil’s nutrient content by adding some quality compost to your mix.
Like any plant, aloe vera does require nutrients to grow and flourish. This is where materials like potting soil come in. Potting soil comprises 50% organic matter, compost, and solid materials like minerals, sand, silt, and clay. The rest is 25% water and 25% air for oxygen.
Specifically for succulents like aloe vera, a fine potting soil or even a seedling (germination) mix can be used because the bark chips are usually smaller. A bark size of 0.2 – 0.3 inches is ideal.
To add more nutrients to this formula, add a couple of handfuls of good compost to your mix.
A good potting soil has the right structure and nutrients to conserve moisture, provide oxygen, and anchor the plant’s roots.
The soil mix is very important to maintaining a healthy aloe. Without a good mix, there is the chance that roots could be damaged, and the plant can suffer and even die. It is essential to take the time to prepare soil mixes well with the right ingredients for the best chance of success.