Succulents are resilient plants that can grow in a variety of conditions. The beautiful fleshy leaves and their hardy nature is what makes them a popular houseplant.
Though they can look attractive in glass terrariums with nothing but rocks under them, Succulents cannot grow in just rocks. This is because Succulents are not epiphytes and use a root system to obtain nutrients and moisture from soil; Without soil, the succulent will die.
Can Succulents Grow Without Soil?
The reason why people are inclined to grow succulents in just rocks is because they treat them as epiphytes. However, this is a common a misconception; Succulents are NOT epiphytes.
Epiphytes, like air plants and orchids, get their nutrients from the air. This makes it possible to grow them without soil. Since they have no attachment to the ground for nutrients, they can grow on top of other plants or objects for physical support and continue thriving solely from air.
Succulents are different; They get their nutrients from soil and water. Meaning, succulents cannot grow without soil. They have extensive roots that absorb nutrients and moisture from the soil.
Can Succulents Grow In Rocks?
Succulents cannot survive for long when grown in just rocks. They may survive for short periods, but will eventually die due to the abscence of nutrients and water. However, it’s possible to prolong the life of succulents growing in just soil by providing them adequate water, nutrients and light.
Make sure the succulent is placed in a location where it receives plenty of sunlight. Succulents need around six hours of bright light each day to thrive.
Use a sprayer bottle to mist the plants with water regularly. If the leaves appear shriveled and/or wilted, it may indicate that the plant is in need of watering.
However, the condition should not be confused with overwatering. Since there are no drainage holes in a terrarium or a glass jar, it’s easy to overwater the plant. If the leaves appear soft and mushy, take it as an indication to adjust the watering frequency.
Succulents growing on just rocks do not have soil to absorb nutrients from, you’ll need to cover the requirements with fertilization; Add fertilizer diluted to ¼ strength in the water that you use to mist the succulents with.
Add Organic Material
Adding organic material provides a medium that the roots can attach to. Coir and spahgnum moss are organic materials that succulents prefer most. These materials will hold the plant in place and provide the support necessary for the roots to grow.
If you use sphagnum moss, you can mist less frequently. The moss stores moisture and allows the succulent roots to absorb it over a period of time. In fact, frequent watering may even be harmful to your succulent in this case.
The Ideal Growing Medium For Succulents
Succulents grow best in well-drained soil. Since they belong to arid regions, they’re adapted to growing in fast-draining sandy soil. Gardeners often improve the drainage of potting soil by mixing small rocks or gravel in it before planting succulents.
Rocks and pebbles help water flow out easily through the soil, which improves drainage. They also create small spaces within the soil layer to help improve aeration, giving more room for the roots to breathe.
Commercial succulent and cacti potting soils are best for growing succulents. These soil mixes are made from a combination of organic and inorganic materials that both improve drainage and nutrient composition of the growing medium.
Growing Succulents in Soil and Rocks
While succulents growing in rocks in glass jars and pots is a common arrangement seen in homes, it’s mostly an illusion. The succulents are not just growing in rocks. They are growing in a minimum amount of soil that will cover the roots and the soil is cleverly hidden by rocks to give the illusion that the succulents are growing in just rocks.
Different types of rocks can be used for the arrangement, but a smaller size will make it easier to hold the soil without making it visible through the glass.
Place a layer of rocks/pebbles or gravel on the bottom and sides of the glass jar. Then, place the succulent and cacti mix in the center. Plant the succulents on the soil, covering the roots with more soil if necessary.
Once the plant is in place, add more pebbles on top to cover the soil that’s visible from the top. You may need to use tweezers to place the pebbles since glass jars have narrow openings.
Once the arrangement is complete, it will look as if the succulents are planted in pebbles/rocks. However, in reality, there’s potting soil between the pebbles, and that is what’s holding the succulent’s roots.
While succulents can grow in rocks, they won’t survive for long unless their requirements – water, nutrients, and sunlight – are fulfilled. That being said, well-drained potting mix specifically formulated for growing succulents is best for growing these plants.