The fuzzy leaves and beautiful blooms of the African Violet (Saintpaulia ionantha) have made them one of the most popular indoor plants of all time, even when another flashy new plant might come along.
They have a reputation for fussiness, but with the right type of soil, you can avoid much of the drama they are known for.
Mixing soil for African Violets gives you control over the pH of the soil and will help you provide the right amount of water, no matter the weather.
It’s not as hard as it looks, with the main ingredients of African Violet soil being minerals and natural materials easily found at garden centers and online.
Let’s look at how to make your own soil mix for African violets and ensure you get the best results.
Table of Contents
African Violet Overview
|Size and Dimensions (Mature)
|15 to 24cm (6 to 9 inches) tall and wide
|Soft, velvety leaves, delicate white, blue, or purple flowers
|Warm, well-lit areas with abundant indirect sunlight or good, broad-spectrum artificial lights
What Type of Soil is Best for African Violets?
African violets need their roots to be kept moist but not wet, with good aeration and drainage, too. They also need a slightly acidic mix with a pH between 6.2 and 6.5. There’s good reason for their fussy reputation!
It’s a lot to balance. The hardest element is the balance between water retention and drainage. Warm weather and bright light will also impact the soil conditions, inspiring resource-intensive new growth from the crown of the plant, so where you place African violets in the home can have a big impact.
Direct sunlight especially will overwhelm the plant, not only drying the soil but stressing the plant so badly it stops being able to retain enough moisture.
Unfortunately, there’s not a lot of margin for error with this plant. African violets are especially vulnerable to root rot and leaf diseases if conditions are too wet. Ailing plants are more vulnerable to other problems and tend to attract pests like mealy bugs and spider mites.
A good potting mix will provide good drainage to prevent stagnation and root death. It will also have good aeration, texture, fertility, and vital nutrients to keep those fuzzy leaves coming.
Some growers avoid the drama by growing in soilless mixtures. This is one of the best ways to reduce the risk of root rot, as most pathogens that cause the condition need soil to survive.
But it brings its own challenges – soilfree mixes have a shorter pot lifespan and lose fertility faster. You must be on top of your fertilization and ready to repot more often.
Ingredients for the Best African Violet Soil Mix
Perlite is the indoor gardener’s best friend. This airy substance is a form of mineral basalt super-heated in kilns until it pops like popcorn. This fluffiness makes it perfect at providing good drainage to any potting mix blend.
It also has some interesting chemical properties that allow it to hold onto essential nutrients and water, supporting root systems and the overall growth of plants.
And because it’s a mineral, it has a neutral pH and doesn’t break down over time. It’s one of my all-time favorite components of any good homemade soil mixture.
Vermiculite is also a mineral – in this case, mica- super-heated until it expands. Vermiculite is layered and flaky, almost like a croissant! Its deep folds and fissures give it excellent water-holding capacity and can also retain nutrients.
It does have its downsides – vermiculite is so good at holding water it can contribute to waterlogging. It also tends to become alkaline over time – that is, the pH becomes too high.
But the rewards it brings are worth it, and it works well in conjunction with other elements, like perlite and organic components that have more give and take when it comes to water.
Also known as pumice, these porous rocks are almost like a naturally occurring perlite – they have much the same properties regarding pH, water holding capacity, and aeration.
Most commercial volcanic stone is ground to round pebbles that range from big and chunky to small size pebbles. While I wouldn’t use a lot in my own African violet blend, a few handfuls will improve the texture of the mix.
I also like to top dress my African violets with a thin layer of smaller stones – it will keep water off the leaves and prevent water spots.
Peat moss is exactly what you’d imagine – a small, springy plant that dried and compressed into large blocks. It has a mildly acidic pH and unbelievable absorbency and can hold its weight in water many times.
It breaks down gradually, like coir, but with a better overall structure and less risk of compacting. Sphagnum peat moss is a similar product, and the two are often used interchangeably.
Peat moss and sphagnum moss have long been the darlings of the indoor plant world, but it has a few significant drawbacks.
Mosses are not sustainably harvested and are taken from delicate ecosystems at a far faster rate than the plants can regrow. I recommend steering clear of it if you can – and there are plenty of more sustainable options out there.
Coco Coir and Coco Peat
Coco coir is a tough, fibrous material made from coconut husk. It’s cleaned, shredded, and dried before being compacted into bricks and sold at garden centers for use as a soil amendment.
Coco coir is very absorbent. It sucks up an astonishing amount of water and holds it for gradual release. It provides even, consistent moisture to plant roots. It’s largely pH neutral but becomes acidic as it decays.
Finally, the best part is that it’s a sustainable product – so long as we eat coconuts, there will be plenty of husks to go around. Putting it in your pots keeps it out of landfill, too.
The big downside with coir is that it will need to be replaced every now and then. It can also become compacted at the end of its life and fail to maintain moist soil. But in most cases, it’ll last until the next time you pot, and you’ll get all its benefits in the meantime.
Also known as rice hulls, rice husks are the outer shells of rice grains removed as part of their processing for food. They’re commonly used as animal bedding, but they’ve started gaining traction as a soil amendment.
They are light and airy, much like perlite, with good water retention too. They’re also very cheap, and as a by-product of agriculture, they’re very sustainable. People are unlikely to give up rice any time soon, so there’s a lot to be had.
Rice husks’ big drawback is that it is not sterile out of the bag and needs a bit of extra work at home before it can be used. It will need to be sterilized by parboiling before it can be added to soil mixes.
Mixing Potting Soil for African Violets
My preferred recipe for homemade African violet soil is one part good quality regular potting mix, one part organic matter like coco coir or peat, one part perlite, and one part vermiculite. This gives good water retention and plenty of nutrition and drainage too.
If you want to grow in a soil-free blend, two parts coco coir or peat with one part each vermiculite and perlite is the way to go.
When growing without soil, soil fertility is the most important thing to watch. During the growing season, fertilize once a fortnight with a specialist African violet fertilizer.
Pasteurizing Your African Violet Soil Mix
To ensure perfect plants with zero root problems, consider pasteurizing your soil before planting. To do this:
- Once blended, place the soil mix onto a disposable oven tray.
- Cover the tray with aluminum foil.
- Heat around 85°C (185°F), checking the internal temperature of the mix with a meat thermometer to ensure consistency.
- Allow it to bake for an hour.
- Carefully remove it from the oven and slowly let it return to room temperature.
Letting the resulting mix rest for a few days before use is also a good idea. You also might need to really pour water extravagantly into the mix and allow it to soak before use to ensure it’s adequately hydrated. This well-treated type of mixture tends to be very dry indeed!
How to Choose the Right African Violet Soil: Blend or Buy
I love to blend my own potting mixes for my indoor plants. No matter how picky the house plants, there’s a way to cook them up just the right blend.
That said, it’s understandable that many folks just don’t have the space or time to blend their own. For those growers, a commercial African Violet soil mix will do the job just fine.
Well-appointed garden centers should have a few different commercial potting mixes that will get the job done. Many have good, natural ingredients that are more sustainably sourced than the usual mix of peat moss or sphagnum, too.
Avoid using regular potting soil on its own. It really isn’t the right kind of soil for African violets. Garden soil is even worse – it’s the natural habitat for many pathogens that can kill off your violet entirely.
Choosing the Best Pots for African Violets
While the right soil mix for your African Violet is critical, it’s only half the story – after all, you need a pot to contain the lot. Choosing a new pot is just as important as getting the right potting mix.
Make sure your new pot is the right size for your plant. If you’re re-potting to a larger pot, aim for no more than an inch or two larger than your current pot.
This will give you room for new root growth without leaving too much dead space out of reach of the roots. New propagations tend to need much smaller pots than the original plant, even if you’re propagating by division.
Cheap and cheerful, plastic pots are the workhorse of most indoor plant enthusiasts. For African violets, they provide a real boost to maintaining the right moisture content in the soil and often have a lot of drainage holes to allow excess water to flow away.
When using plastic pots for African violets, make sure you have at least three well-spaced drainage holes. I also suggest you go low – violets don’t need deep pots, so a wider and shallower pot will give them plenty of space without leaving an unreachable area to stagnate at the bottom.
Clay pots are elegant and infinitely reusable. They come in two types – glazed or unglazed – and a captivating spread of different colors and designs.
Glazed pots are the colorful ceramics that populate your local garden center. They’re great for African violets, as they hold moisture within them well.
They also help keep the soil temperature even by insulating against sudden changes brought on by direct sunbeams or drafts.
Unglazed pots are simpler, usually made of terracotta. Without the glaze, water absorbed by the clay evaporates into the air outside the pot.
This is both a blessing and a curse- they can cause your soil to dry out quite quickly. But if you habitually over-water your plants, terracotta is a fantastic choice. It’ll help stop water from stagnating at the bottom of the pot.
The thing to check with clay pots of all types is drainage. Many only have one drainage hole at the bottom of the pot. Good drainage is paramount for African violets, so you’ll need to make sure that the hole stays clear and water can freely flow.
Self-watering pots are a clever way to keep an African violet’s soil nice and moist. These pots are typically two parts – an inner pot liner that holds the plant and an outer pot that holds both the liner and the water reserves.
Depending on the variety, they can be as simple as a deep well underneath the inner pot, connected by a chimney-like passage, or more involved versions with wicks that lead into the soil, water level indicators, and the like.
No matter the design’s complexity, a self-watering pot is a great choice for African violets. They provide consistent moisture as long as the reservoir is filled.
If you’ve decided to use a soilless mix, it’s a good idea to use a mixture with less absorbency – one part each perlite, vermiculite, and an organic element like peat or coir is best. The soil doesn’t need to absorb as much water if there’s always plenty to hand.
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