Moss can either be the best thing to happen to your potted plants—or they can be the worst! I’ve experienced both failure and success in using moss. Let me share with you how to properly use moss for the most success!
Moss, such as peat and sphagnum, is a useful soil amendment that does not compact and can help increase moisture. However, moss can absorb and retain excess amounts of water and can be harmful to the environment.
Moss is one of the most popular growing mediums available, so it’s not unusual that people often ask about using moss in potted plants. While they can be incredibly helpful, what are the instances where it might be better to avoid them? Let’s dive into it!
Some of the pros of using moss include its ability to retain high amounts of water and lessen the chances of compaction.
Sphagnum moss is highly absorbent and can hold a lot of water. It also evenly disperses water. Peat moss is also commonly used in commercial potting mixes due to its ability to retain moisture and nutrients.
Sphagnum moss can hold and absorb up to 20 times its weight in water.
This is due to the unique cellular structure of sphagnum moss leaves, which consists of dead cells. These dead cells are what allow sphagnum to absorb and hold so much water.
Heavy-drinking plants, like maidenhair ferns, will benefit from the use of peat and sphagnum moss.
What’s also great about using moss, specifically sphagnum moss, is that they don’t just absorb large amounts of water. The sphagnum will evenly distribute moisture to the rest of the moss, which is great for potted plants that need even watering.
If you’re struggling with your potted plants losing moisture faster than the plant can absorb, you might find sphagnum moss and peat moss useful!
Read our article to learn the differences between peat humus and peat moss.
Sphagnum moss is lightweight so it does not compact easily. Most high-quality sphagnum and peat can be used for years and will remain soft and airy.
Dense, compacted soil has reduced porosity. making it more difficult for plant roots to absorb the moisture and nutrients they need.
Sphagnum moss, however, almost always stays light and fluffy.
Oftentimes when we purchase sphagnum moss, it comes in compressed bricks to help save on shipping costs. But after you rehydrate and stir it, it will become quite soft.
I have used moss in potting mixes and grown plants solely in sphagnum moss. Upon checking, all of the moss today still has a very light and soft texture, despite being used for several months!
The 2 major cons of using moss for potted plants are that it can retain excess water and they are not eco-friendly material.
We’ve finished talking about the benefits of using moss. But are there any disadvantages? Keep reading to learn more and decide whether or not you should use it.
Moss is very absorbent so it can cause root rot and overwater. The use of sphagnum moss is also detrimental for moisture-sensitive plants and plants growing in cold environments, where water evaporates more slowly.
Although I praised moss earlier for its ability to hold and absorb water, there is a flip side. This is natural and there will always be an opposite to things.
Its ability to absorb water isn’t necessarily a bad thing. But if it’s not used carefully, sphagnum and peat moss can easily get soggy.
So if you tend to overwater and have plants that are extremely sensitive to moisture, using moss might not be the best idea. If you live in a colder region, it might not be ideal either.
Plant enthusiasts have probably been told hundreds of times to reduce the water they give their house plants during the winter. This is because water takes longer to evaporate in cooler temperatures.
Remember, moss is extremely absorbent and will take longer to dry in cold environments. Excessive amounts of moisture are frequently the cause of root rot, which is essentially impossible to reverse.
Despite its popularity, peat moss is not a renewable resource and typically requires wetlands to be drained and destroyed for harvest. Harvesting sphagnum moss is not as harmful but it can still be damaging to the environment.
Much of the peat moss used today comes from peat bogs that have been thriving for hundreds and thousands of years.
Bogs and wetlands help reduce the effects of global warming by collecting large amounts of carbon.
After many years, dead moss will accumulate and settle at the bottom of the bog. Forharvesting, peat bogs are typically drained of water and destroyed to collect the peat moss underneath.
While peat bogs are sometimes restored after harvest, it can take 5–20 years for plant life to return. But of course, this growth will never be the same as before.
The same applies to salt marsh hay, another popular material commonly used as mulch.
Read more in our article on salt marsh hay for mulch.
Sphagnum moss, however, is typically made up of live moss that is cut from the surface of peat bogs and then dried. Because of this, the harvesting process for long fiber sphagnum moss is not as harmful and does not require harvesters to drain bogs.
Long fiber sphagnum moss can be better to use instead of moss but it will still take several years to grow back.
Everything has its cost and it’s our responsibility to be aware of this and work with things as best as we can.
Moss can be used for potted plants by mixing it into the soil, using it as a top dressing, and choosing it as a replacement for soil.
Now that we’ve discussed all the advantages and disadvantages of using moss, let’s talk about the ways you can use it for your potted plants!
Peat moss can be mixed in soil to increase moisture retention. Conversely, sphagnum moss should not be used in potting mixes, as it will absorb too much water.
If you have peat moss, you can easily include this in your potting mix. Each plant will have its own needs.
A soil-free potting mix that you can make ahead of time can consist of:
For an eco-friendly substitute for peat moss, consider using coco coir.
However, I don’t recommend mixing long-fiber sphagnum moss with soil. Since they are incredibly absorbent, they are risky as they can lead to overly moist potting mediums.
Sphagnum moss is better used as a top dressing, which I’ll discuss in the next section.
Besides that, sphagnum moss is also used in kokedama, a Japanese planting method where plants are wrapped in a combination of mud and sphagnum moss shaped into balls.
If you’re an experienced gardener looking to try something new, consider using your sphagnum moss for kokedama!
Use sphagnum moss as a top dressing by covering the top of soils with 2 inches of sphagnum moss. This prevents water from evaporating immediately and can help retain soil moisture.
If your plants need extra moisture and you consistently have issues with providing the right amount, sphagnum moss can be great as a top dressing.
To use sphagnum moss as a top dressing, just add a light 1–2 inch layer of sphagnum moss on top of the soil. If you only have peat moss, it’s better to mix it with potting mediums.
There is no need to pack it down. Simply lay it loosely on the top of your potting soil.
If you’re worried about your soil, read our article, “Does Potting Soil Go Bad?”
This method of using sphagnum moss as a top dressing is great for indoor and outdoor potted plants because it will help keep the moisture in and stop it from evaporating too quickly.
This isn’t ideal for potted cacti or succulents, however, as this will bring too much moisture.
Sphagnum and peat moss can be used as an effective growing medium and can last for 3 years. Plants grown in moss should only be watered when dry. They must be fertilized regularly, however, as moss is not as nutrient-rich as potting soil.
Sphagnum moss is the best type of moss to use for growing potted plants because it is less harmful to the environment and can be used alone! Peat moss can also be used to replace soil but is not as eco-friendly.
For this method, I recommend keeping the plants in transparent containers so you can easily check the moss. The plant and its roots should be placed in the middle of the container and surrounded by sphagnum.
Again, the sphagnum moss should remain fluffy and not be packed down.
Water the plant when the top of the moss is dry and there is no longer any condensation forming inside the container. As always, make sure there are drainage holes to prevent the excess water from killing your plant.
While there really is no good or bad type of moss for potted plants, good quality moss should last for at least 3 years.
This sphagnum moss here is perfect for growing plants and lasts for a long time!
This method of using sphagnum moss as a substrate is commonly done with orchids.
Plus, if you ever change your mind, these plants will develop strong root systems in the moss and can easily be transferred to soil if necessary!
What is the difference between sphagnum and peat moss?
Peat moss is the decayed plant life at the bottom of bogs and can only be harvested after wetlands are drained. Sphagnum moss comes from the live plants at the surface of peat bogs and only need to be cut and dried and do not require draining of bogs to harvest.
What plants benefit from moss?
Carnivorous plants, such as the Venus flytrap and sundew, typically require swamp-like conditions and will thrive from being grown in moist and low-nutrient sphagnum moss. Orchids are also commonly grown in sphagnum moss due to the moss’ ability to provide even moisture.
Why is moss growing in my potted plants?
Potted plants kept in overly damp and shady conditions can sometimes grow moss. Moss requires moist and shady environments to survive and can be carried by the wind and grow in potted plants.
How do you get rid of moss in potted plants?
Ferrous sulfate can be safely used to get rid of moss in potted plants. It is found in most commercial moss control and will kill moss. But unless the conditions are changed, the moss will only return.
Moss is an excellent medium that is lightweight and can be used in potted plants to help increase and retain more moisture. Moss can be included in potting mixes, used as a top dressing, or used to replace soil.
However, moss can also be problematic due to its ability to retain excessive quantities of water. It is also commonly harvested by mining peat bogs, making it damaging to the environment.
- “Sphagnum Moss” by n/a in University of Wisconsin-Madison
- “Peat” by n/a in University of Florida, University of Kentucky, and Texas A&M University
- “Is There A Problem With Sphagnum Peat Moss?” by Sherry Rindels in Iowa State University
- “A Comparison of Coconut Coir and Sphagnum Peat as Soil-less Media Components for Plant Growth” by Jason Holman, Bruce Bugbee, and Julie K. Chard in Utah State University