Rosemary bonsai soil, Ref. 2949

Rosemary bonsai soil

Choosing the right soil for a rosemary bonsai is one of the key factors for successful cultivation. Rosemary needs a light, well-aerated, and fast-draining substrate, but its roots should not constantly dry out.

Required soil properties:
- excellent drainage so that water does not stagnate;
- lots of air around the roots;
- medium moisture holding capacity;
- low organic matter content;
- a well-defined structure in which the particles do not become compacted quickly;
- pH approximately 6–7.5
- particle size of approximately 1–5 mm; all fine fractions (~less than 1 mm) must be sifted out and removed.

A good base mix for mature rosemary:
Akadama 30%
Pumice 30%
Lava 20%
Coarse quartz sand 10%
Coconut coir 10%

Pumice provides porosity and aeration.
Lava maintains structure and drainage.
Akadama retains some water and nutrients.

If the rosemary is kept on a sunny and windy balcony, you can increase moisture retention by adding organic matter (up to 15–20%).
If the plant is kept in a cool room or the potting mix remains wet for a long time, it’s best to reduce the organic content to 5–10%.
In this case, the pot’s drainage holes must be large enough and must not become clogged with potting mix. A mesh screen over the holes is necessary.

For rosemary, it’s better to have a slightly more dry and well-aerated growing medium than to keep it constantly wet.

At the same time, it’s important to differentiate between “dries quickly” and “drains well.” A purely mineral mix with particles that are too large can dry out so quickly that you’ll have to watered it several times a day in the summer.

A mineral substrate contains practically no nutrients. Therefore, after repotting, you shouldn’t expect the nutrients from the fresh soil to last the whole season.

For rosemary bonsai, it’s best to provide regular nutrition, especially during periods of active growth. Don’t make the soil overly organic just to build up a nutrient reserve—it’s easier to control nutrition with fertilizer.

500 ml package
When purchasing 3 or more packages, the price per package is 2.60 €