Quick Summary
- Maifan stone (also called maifanite or "medicine stone") is a natural mineral rock rich in over 40 trace elements and minerals that benefit plant health.
- It slowly releases calcium, magnesium, iron, zinc, and other micronutrients into the soil, acting as a long-term mineral supplement for your plants.
- Maifan stones improve drainage, aeration, and water quality while gently stabilising soil pH.
- Ideal for bonsai mixes, succulent substrates, and any potting blend where mineral nutrition and drainage are priorities.
- Typical application rate: 10–20% by volume in a standard potting mix.
What Is Maifan Stone?
Maifan stone is a naturally occurring igneous rock that has been used in East Asian horticulture (and traditional medicine) for centuries. The name comes from the Chinese 麦饭石 (màifàn shí), meaning "rice meal stone" — a reference to its granular, rice-like texture when crushed.
What makes maifan stone remarkable for plant growing is its mineral composition. Each granule contains a complex matrix of:
- Calcium — essential for cell wall strength and root development
- Magnesium — the central atom of chlorophyll, critical for photosynthesis
- Iron — prevents chlorosis (yellowing leaves) and supports enzyme function
- Zinc — important for growth hormone regulation
- Potassium — regulates water uptake and disease resistance
- Trace elements — including manganese, copper, molybdenum, and selenium
These minerals are locked within the stone's crystalline structure and release slowly over months and years as water passes through the medium. Unlike liquid fertilisers that deliver a burst of nutrients and then wash away, maifan stone provides a gentle, continuous supply of trace elements — much like how minerals naturally weather from rocks in a forest floor.
Benefits of Maifan Stone for Plants
1. Long-Term Mineral Supplementation
Most potting mixes are deficient in trace minerals. They contain the big three — nitrogen, phosphorus, and potassium — but often lack the full spectrum of micronutrients that plants need for optimal health. Maifan stone fills this gap without the risk of over-fertilising.
This is particularly valuable for: - Bonsai grown in inorganic substrates (akadama, pumice, lava rock) that contain few nutrients of their own. - Succulents that grow in lean, mineral-based mixes and benefit from slow-release trace elements. - Native plants that evolved in mineral soils and can be sensitive to synthetic fertilisers.
2. Improved Drainage and Aeration
Like pumice and lava rock, maifan stone granules create air spaces in your potting mix. This prevents compaction, allows oxygen to reach roots, and ensures excess water drains rather than pooling. For plants prone to root rot — which is most plants, if we are honest — improved drainage is always welcome.
3. Water Quality Enhancement
Maifan stone has a well-documented ability to adsorb impurities from water, including chlorine, heavy metals, and organic contaminants. When used in potting mixes, it effectively acts as a water filter, delivering cleaner water to roots. Some growers also place maifan stones in their watering cans or reservoirs to condition water before use.
4. pH Stabilisation
Maifan stone has a mildly alkaline character (typically pH 7.0–7.5) and acts as a gentle buffer. In acidic potting mixes — which many peat-based blends become over time — it helps stabilise pH within the range that most plants prefer (6.0–7.0). It will not dramatically shift pH, but it resists the gradual acidification that causes nutrient lockout in long-term plantings.
5. Beneficial Microbial Activity
The porous surface of maifan stone provides an excellent habitat for beneficial soil microorganisms. These microbes form symbiotic relationships with plant roots, aiding nutrient uptake and disease resistance. A biologically active root zone is a healthy root zone.
How to Use Maifan Stone
In Bonsai Mixes
Bonsai growers have been early adopters of maifan stone in Australia, and for good reason. Inorganic bonsai substrates (akadama, pumice, lava rock) provide excellent drainage and structure but are nutritionally inert. Adding maifan stone introduces a natural mineral source that complements regular fertiliser applications.
Recommended bonsai mix with maifan stone: - 40% akadama - 25% pumice - 20% lava rock - 15% maifan stone
This gives you the water retention of akadama, the drainage of pumice and lava rock, and the mineral supplementation of maifan stone — a well-rounded mix that covers all bases.
In Succulent and Cacti Mixes
Succulents and cacti thrive in mineral-rich, fast-draining substrates. Maifan stone is an excellent addition:
Recommended succulent mix: - 40% coarse sand or fine pumice - 30% quality potting mix (low peat content) - 20% maifan stone - 10% perlite
The maifan stones provide both structure and a slow-release mineral supply that supports steady, compact growth — exactly what you want for healthy succulents.
In General Potting Mixes
For houseplants, herbs, or garden containers, adding 10–15% maifan stone by volume improves drainage and provides trace minerals that standard potting mixes lack.
Simple upgrade for any potting mix: - Take your existing potting mix. - Add 10–15% maifan stone and mix thoroughly. - Pot up as normal.
As a Top Dressing
A layer of maifan stones on the soil surface serves several purposes: - Reduces moisture evaporation from the top layer. - Creates an attractive, natural-looking surface. - Minerals leach into the soil with each watering. - Discourages fungus gnats from laying eggs in the topsoil.
Use a single layer of medium-sized granules — just enough to cover the soil surface.
In Water Features and Aquaponics
Beyond potting mixes, maifan stone is used in aquariums, ponds, and aquaponic systems to: - Condition water and adsorb impurities. - Provide trace minerals for aquatic plants. - Stabilise water pH for fish health.
Comparison with Other Mineral Amendments
| Property | Maifan Stone | Lava Rock | Pumice | Zeolite |
|---|---|---|---|---|
| Mineral release | Excellent — 40+ minerals | Moderate — iron, magnesium | Low | Moderate |
| Drainage | Good | Excellent | Excellent | Moderate |
| Water retention | Low–moderate | Low | Moderate | High |
| pH effect | Mildly alkaline (stabilising) | Neutral | Neutral | Variable |
| Water purification | Yes | No | No | Yes |
| Weight | Medium | Heavy | Light | Medium |
Maifan stone's unique advantage is the breadth of minerals it provides. While lava rock and pumice excel at drainage, they offer limited nutritional value. Maifan stone combines structural benefits with genuine mineral supplementation.
Application Rates
| Use Case | Maifan Stone % | Notes |
|---|---|---|
| Bonsai mix | 10–20% | Pairs well with akadama and pumice |
| Succulent/cacti mix | 15–25% | Supports mineral-dependent species |
| General potting mix | 10–15% | Improves any standard mix |
| Top dressing | 1–2 cm layer | Decorative and functional |
| Aquarium/pond | 5–10% of substrate | Conditions water and provides minerals |
Tips for Australian Growers
- Rinse before use. Maifan stone can be dusty straight from the bag. A quick rinse in a sieve removes fine particles that could clog drainage.
- Pair with fertiliser, do not replace it. Maifan stone provides trace minerals, not macronutrients. Continue your regular fertilising routine for nitrogen, phosphorus, and potassium.
- Reusable. Like pumice, maifan stone does not break down. When you repot, sieve it out, rinse, and re-use.
- Store dry. Keep unused maifan stone in a dry location to prevent algae growth on the granule surfaces.
Looking to add maifan stone to your growing mixes? We stock Mineraland Maifan Stone in sizes suited to bonsai, succulents, and general potting — browse our full bonsai soils collection to build the perfect mineral-rich substrate.