How to choose top dressing stones for succulents? A step-by-step guide to picking them
Hong Zhao Yuan
Hong Zhao Yuan
Yinqueshiting
00:00/02:53
BGM: Hong Zhao Yuan
As a devoted "succulent slave", every step and every part of growing succulents requires repeated deliberation, for fear that the succulents will be unhappy, fail to grow well, get root rot, develop rotting leaves, become leggy, go bald...... Choosing top dressing stones is no exception. I often receive comments or messages from fellow succulent growers asking which top dressing stone to choose. So, which one should you actually choose?
- Advantages of top dressing stones -
What are the benefits of using top dressing stones?
1. Beautiful, makes photos look more impressive
2. Prevents soil from splashing when watering or during strong winds
3. Prevents the surface soil from caking, ensuring soil breathability
4. To a certain extent, can prevent the growth of insect eggs
So top dressing stones are actually quite important
- Classification of top dressing stones -
Top dressing stones are broadly divided into three categories: soft top dressing, hard top dressing, and sandy top dressing.
1. Soft top dressing: can be crushed by hand, such as akadama soil, kanuma soil, maifan stone, etc.
Suitable for: succulents that love clustering and rosette shapes, because the texture is soft, there is no need to worry about the leaves being damaged by contact with the top dressing during growth.
2. Hard top dressing: volcanic rock, green zeolite, etc., with a relatively hard texture.
Suitable for: succulents intended to become old stumps. This type of stone, especially green zeolite, has an advantage -- snails cannot climb up, and if they do climb up, the soft succulent will be cut by the green zeolite. If a succulent has been bitten by a snail, try switching the top dressing to green zeolite.
3. Sandy top dressing: as the name suggests, it is sand (river sand, sea sand) and the like. For growing succulents at home, it is still not very recommended, as it will cake together with the granular soil below, adding trouble when watering.
Now let's take a look at the pros and cons of different top dressing granules~
Soft top dressing stones
Kanuma pumice (Shikinshoku): top dressing stone, mixed granular soil
Pros: a type of volcanic stone, acidic pH, relatively light weight, excellent drainage, moisture retention, and breathability, can prevent bacterial growth and root rot. For many plants whose roots are afraid of heat, covering the roots helps them safely get through summer.
Cons: no fertility.
Use: can be used for top dressing, or used alone. If mixed with other granules, it can produce better results.
More commonly used for orchid cultivation
Diatomite: top dressing stone, mixed granular soil
Pros: fine, loose, light, porous, water-absorbent, strongly permeable, and the diatomaceous element it contains can kill insects physically.
Cons: no fertility.
Use: can be used for top dressing, or mixed with other granules
Maifan stone: top dressing stone, mixed granular soil
Pros: a type of volcanic rock, contains various minerals and trace elements, high hardness, strong permeability and drainage. It can stabilize, improve, and balance the physical mechanism of the soil, and can adsorb harmful substances and bacteria.
Cons: any cons? Too cheap?
Use: can be used for top dressing, or mixed with other granular planting media.
The current mainstream top dressing stone -- maifan stone (the favorite of Korean greenhouses)
Graptopetalum snow claw top-dressed with maifan stone
Kanuma soil: top dressing stone, mixed granular soil
Pros: produced in the volcanic area of Kanuma, Japan, formed from lower-layer volcanic soil, strong breathability and water permeability, slightly acidic pH, can prevent bacterial growth and root rot, rich in various minerals.
Cons: soft texture and easily crushed, not suitable for cuttings and root development.
Use: can be used for top dressing, or mixed with other fine granules.
Kanuma soil with a more powdery texture; it is recommended to replace it once a year after use (image from the internet)
Kanuma soil (larger size) used as top dressing
Akadama soil: top dressing, mixed soil
Pros: good water retention and breathability, rich in minerals, light, cheap.
Cons: easily crushed
Use: can be used for top dressing, or mixed with other granules.
1-3mm akadama soil
Dried akadama soil top dressing
Wet akadama soil top dressing
Kiryu sand: top dressing stone, mixed granular soil
Pros: volcanic sand, contains a large amount of iron oxide, hard texture, not easily crushed, very good permeability and drainage, can prevent bacterial growth and root rot, rich in various minerals.
Cons: not very cheap.
Use: can be used for top dressing, or mixed with other granular planting media.
Pumice: bottom drainage stone, mixed granular soil
Pros: loosens soil, strong water retention, antibacterial, small temperature fluctuations, can promote root growth.
Cons: no fertility, easily pulverizes over time, light weight.
Use: needs to be mixed with other granular media; not recommended as a top dressing stone, as it will float up when watering.
Pumice (mostly used for bottom drainage, image from the internet)
Hard top dressing stones
Iridescent stone: top dressing stone, mixed granular soil
Pros: pumice, zeolite (green zeolite), volcanic rock and other granules mixed together, maintains pH value, good drainage and breathability
Cons: it is the most expensive.
Use: can be used for top dressing, or mixed with other granular planting media.
Actually this pot's top dressing is rainbow stone, not iridescent stone (the difference will be explained at the end)
Green zeolite: top dressing stone, bottom drainage stone, mixed granular soil
Pros: a mineral, soil improver, can retain fertilizer and water, prevent pests and diseases, has a certain purifying function, and can adsorb harmful substances in the soil.
Cons: not very suitable for Haworthia and other twelve-series succulents; the stone is too hard and may scratch the succulent's leaves and roots.
Use: can be used for top dressing and bottom drainage media, or mixed with other granules
Green zeolite really has high aesthetic value (image from Taobao)
Volcanic rock: top dressing stone, mixed granular soil
Pros: porous stone formed by magma solidifying directly after a volcanic eruption. Light, loose and porous, good breathability, rich in minerals and various other trace elements.
Cons: relatively hard, not suitable for some succulents.
Use: can be used for top dressing, or mixed with other granules.
Volcanic rock top dressing with fairly good aesthetic value
Small clay pebbles: bottom drainage for pots without holes, mixed soil
Pros: ceramic granules fired at high temperature, relatively light, large granule size, high internal porosity, good drainage and breathability, mostly used as bottom drainage media for succulents.
Cons: no fertility, not conducive to root development.
Use: mostly used as bottom drainage media for succulents, or mixed with other fine granules.
Still the favorite top dressing for orchids
Sandy top dressing
River sand: top dressing stone, mixed granular soil
Pros: high water retention, beautiful color.
Cons: not suitable for cuttings, no fertility (said to be not very breathable).
Use: can be used for top dressing, or mixed with other granules.
Washed river sand (image from Taobao)
As for the editor's own experience,I prefer using maifan stone and akadama soil(for size, 3-6mm is not recommended; 1-3mm is better, very delicate, and still fairly cheap), and fake iridescent stone (called rainbow stone, with main ingredients -- volcanic rock, green zeolite, river sand, pumice, etc.) has a better top dressing effect than the real one
While the real one -- iridescent stone, full name German Lechuza iridescent stone (main ingredients are zeolite, pumice, volcanic rock, etc.) -- is not small in size, and compared with the fake iridescent stone, it is actually less suitable for top dressing.
PS: when buying top dressing stones, buying a whole bag or half bag is more cost-effective
- Review of the previous issue -