In order for cacti to get through the winter well as houseplants in this country, the substrate should also be selected appropriately. Luckily, you can mix the cactus soil yourself. This is what you need to keep in mind!
Mix cactus soil yourself: Difference to conventional potting soil
The special thing about the cactus substrate is its composition. It is specially adapted to the needs of shallow-rooted plants and differs from conventional potting soil. We summarize the most important differences:
1. Drainage:The potting soil can store moisture, which is then gradually absorbed by the plants. However, cacti and succulents need extremely permeable soil. They cannot tolerate even a small amount of waterlogging and will die. Good drainage is the be-all and end-all of a cactus’s healthy root system.
2.Composition:The potting soil contains, among other things, peat moss, tree bark and vermiculite - all materials of organic origin. In contrast, cactus soil is primarily made up of pumice, gravel and sand, and also contains small amounts of perlite, peat moss and coconut fiber.
3.Soil density:Dieconventional soil for houseplantsis significantly denser than cactus soil. The substrate for exotic plants, on the other hand, scores points with its outstanding stability, does not clump together and allows good ventilation.
Basically, the following applies: cactus soil dries very quickly, has a low soil density and contains predominantly inorganic materials. The proportion of humus in the substrate can vary greatly from species to species. The rule of thumb applies: orientate yourself on the natural location of the plants. Exotic plants that like it particularly sunny and grow in dry and sandy areas in their homeland need few nutrients and more minerals. And vice versa: Cactus varieties that grow in lowlands need a higher proportion of humus.
Substrate for cacti: an overview of the components
A high-quality cactus soil is made up of several components. These include, among others:
1. Conventional potting soil. Do not use garden soil, it may contain bacteria and fungi. Fertilized potting soil is also unsuitable - the fertilizer will damage the roots. Cacti are not designed for our latitudes and are sensitive to native pathogens.
2. Quartz sand, gravel and lava rubble for better drainage. Under no circumstances should you use play sand as it thickens very quickly. The consequences – poor drainage and waterlogging – often lead to rotting roots and wilting cacti.
3. Peat moss or coconut fiber – regulate the pH of the soil. Dose very carefully and only add small amounts to the substrate.
4. For heavily consuming varieties you can add a little compost.
5. Charcoal has an antibacterial and fungicidal effect and can prevent diseases and essentially disinfect the substrate. This keeps the roots healthy.
5. Perlite improves permeability and improves soil.
Mix your own cactus soil: recipe and variations
Universal recipe:
The recipe for cactus soil is super simple. First mix quartz sand, gravel and/or lava quarry with a grain size of 4 mm in a ratio of 1 to 1. Then mix perlite and pumice stone in a ratio of 1 to 1 in another container.
A universal soil is made up of 40% potting soil, 40% gravel and sand mixture and 20% perlite and pumice stone.
Recipe for heavy eaters:
30% humus, 40% gravel and sand mixture, 10% pumice, 10% charcoal and 10% coconut fiber.
Recipe for weak eaters:
Mix potting soil, sand mixture with grain size 6, pumice stone and pine bark in a ratio of 3:3:1:1.
Do cacti need fertilizer?
Cacti do not need fertilizer if the substrate contains growing or potting soil. In some cases you can incorporate some fresh compost, but it should really be a maximum of 1/3 handful per 20 liter bucket.
The needs of the most popular varieties at a glance
Cacti that prefer a mineral substrate belong to the following genera:
- Ariocarpus
- Astrophytum
- Aztekium
- Echinocactus
- Obregonia
Cacti that thrive in mineral-humus substrates belong to the following genera:
- Echinopsis
- Harrisia
- Myrtillocactus
- Opuntia
- Polaski
- Reuben
- Trichocereus
Cacti that prefer a humus-rich substrate are:
- Acanthocereus
- Hylocereus
- Persia
- Rhipsalis
- Selenicereus
This is how you mix the ingredients correctly
For the cactus soil, simply fill the ingredients first, the growing soil or potting soil or humus into the pot. Spray the soil with water first so you don't have to inhale dust while mixing. Alternatively, you can also wear a face mask.
Then add the sand mixture and work it well into the soil evenly. Then add the charcoal, coconut fibers and pine bark and mix the whole thing well. Then test the pH - if it is low, you can incorporate some peat moss.
Store and use cactus soil correctly
First let the substrate dry and then store it in airtight containers in a dark and cool place. You can also use the soil for succulents; they have similar soil requirements and are also shallow-rooted. Thick-leaf plants and bonsai trees also thrive in sandy substrates.
Also read:Houseplants for dark locations: These beautiful plants will transform your home into an oasis!
