Do succulents need soil to grow? Can succulents survive in terrariums without soil? Can succulents grow on rocks, pebbles, sand, moss or driftwood?

We see these beautiful arrangements very often. Succulent in just about any container you can imagine. The more unusual the container, the better it is for that WOW factor. The quest to find the most unusual and unlikely container for succulents is part of the charm and fun of potting and putting a stunning arrangement together. And they truly are beautiful and stunning to look at. But I hear this question asked time and time again, can succulents survive in these arrangements without soil?

The quick answer is yes

They will survive without soil. But will they thrive? Not for long. Think of these as short-term, fun projects and not meant to last for a very long time.

Succulents may look like epiphytes, but they have very different growing habits and needs. Epiphytes are plants that grow on the surface of a plant and gets their nutrients from the air, rain and their surroundings. Some commonly known epiphytes are orchids and air plants. With the exception of tropical or holiday cactus, (Christmas Cactus is a popular one), which are considered epiphytes by nature and have different growing habits and needs from desert cacti.

In the wild, succulents and are often found in environments that would otherwise be uninhabited by other plants. Most come from dry areas, deserts and semi-deserts. Others are found in mountainous regions and rain forests. Conditions that are normally too harsh for other plants to survive, such as high temperatures and low precipitation have made these plants extremely hardy and adaptable. Some succulents are also naturally found in sea coasts and dry lakes, which can be detrimental to other plant species because of their extreme levels of dissolved minerals.

Due to their harsh native habitats, succulents are naturally more adaptable to less than ideal conditions. This is why succulents can survive for a long time in these arrangements that seem impossible for most plants to last even a couple of days.

Another characteristic of succulent plants that make them good candidates for these arrangements without soil is their ability to store water. Succulents have water storage tissues that make them drought resistant. These plants typically store water in their leaves, their stems, or their roots. They have adapted to survive very dry, arid conditions. They do not need to be watered frequently and do not need a moist soil  to survive.

Why succulents need soil

 

Succulents, unlike other houseplants, do not need a highly organic medium to survive. Meaning they do not need to be planted in a soil that are rich in nutrients. But they still need a certain amount of organic and inorganic matter in their growing medium in order to thrive. Even tropical cactus, which are epiphytes, require some sort of soil in their medium to thrive. This is because in cultivation, as opposed to their natural habitat, they have grown accustomed to being grown in some sort of soil mixture.

 

So when you see these arrangements of succulents in small terrariums with sand or gravel, or on rocks or driftwood and you wonder…can I grow succulents in these?

 

While the quick answer is yes, you need to take some things into consideration. Succulents, due to their hardy nature, can survive in these arrangements for an indefinite amount of time depending on how you care for them and the environmental conditions they are exposed to.

Succulents are able to survive in these conditions indefinitely, but these are not ideal conditions in which they can thrive. Eventually, the succulents will start to root and look for a more suitable medium in which to grow in. Succulents planted in small containers, peat moss, sand or driftwood will eventually outgrow its container. Some succulents do not stay small and will eventually need to be potted in a bigger container.

Once they start outgrowing these arrangements, the plants can be removed and re-potted in a more suitable succulent potting mix. If left in these arrangements, they will not thrive and may eventually die.

So while these projects are beautiful and fun to make, you can think of them as short-term arrangements and not meant to last for a long time. Also, accept the fact that some of your plants may die and that you may lose some of your beloved plants. The fun part is starting a new project and seeing the results of your labor.

Two Things to Consider when using Terrariums without Soil

The first two things you want to think about when growing succulents in small terrariums are water and light. Are they receiving enough light? Are they being watered too much? Succulents in small containers like terrariums without holes do not need as much water as potted succulents. An easy way to kill your plants is to water them too much and not give them enough light. Succulents in terrariums that do not receive adequate sunlight and are constantly moist is a recipe for disaster.

How to Water

The rule of soaking your plants and giving them a good watering until water drains out of the hole obviously does not apply here. The best way to water your plants in terrariums without holes is to mist them using a spray bottle or lightly water them using a dropper or syringe  to avoid overwatering. You do not need to do this often.

A good sign to know that your plants need more water is when they start to shrivel and the leaves look wilted. When you touch the plant and it feels flat and not plump, it is a sign that the plant is in need of water. Be careful not to confuse this with an overwatered plant. Often, an overwatered plant will also shrivel and wilt, and a common mistake is to water the plant more, causing more of a problem. An overwatered plant can also be mushy and soft. The best way to tell is the plant is under or over watered is to pay attention to your watering habits. If you have been watering your plants on schedule and the plants are well watered, then they are mostly being overwatered. Cut back on watering to see if the plants show signs of improvement.  If you know you have neglected your plants for a while and they start to shrivel, then you know they are in need of more water.

Make sure the plants are receiving adequate light and kept in a bright location. This is important to avoid rot. Succulents that are moist and do not receive enough light are more susceptible to rot and death. Pay attention to how your plants look and move the container to a brighter location if needed, or to a more shaded location if sunburned. There are tools you can use such as moisture meters and hygrometers to check for moisture in the air. Please click on my resource page for product recommendations. 

How to prolong the life of succulents without soil

So you really want to make that succulent driftwood arrangement you have seen on Pinterest. Or you really want to try out that succulent wreath arrangement and hang it on your front porch. Here are some tips to make your succulents last in these locations without using soil.

Add nutrients or fertilizer

You may consider fertilizing the plants to give them nutrients that they would otherwise be getting from the soil or potting mix. You can do this by adding diluted fertilizer about 1/4 or 1/2 strength into the water you will use to water or mist the plants. This way you are providing the plants some nutrients they need to grow.

Without soil, the succulents need to attach to something. You can hot glue the succulents onto the driftwood or attach them using wires. But having something that your succulents will attach and grow into that will help hold the moisture in for the plants will help prolong their life in these arrangements.  

Suggested Materials to Use:

Coir or coco fiber

Sphagnum moss

Attach the moss or coir onto the driftwood. Attach the plants on the moss or coir. When plants start to root after a few weeks, the coir and moss will help hold the plants. The plants will have something to grow into and its roots to grab onto.

Lightly mist every few days or so to prevent the plants from drying out. Sphagnum moss holds in more moisture and may not need to be misted as frequently. You may also want to consider adding nutrients in the water to feed the plants. Add 1/4 to 1/2 strength fertilizer in the water. You can do this once a month or every other time you mist the plants. 

Using materials such as moss or coir will help your plants last longer in these types of arrangements before they need to be transplanted and repotted. This way you can enjoy the fruits of your labor longer.