Whether you have some moss growing on your roof or you’re planning to plant some moss in your walkway, you might be wondering how long moss will last. Will moss slowly disappear over time? Or is it here to stay?
Moss doesn’t have a determinate lifespan and can easily live for over 10 years, as long as the conditions continue to be suitable for moss growth. Even after moss dies, wind can sweep it away, allowing new moss to take its place within 2-4 months.
Let me help clarify why moss can live so long and exactly what conditions allow moss to thrive.
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How Long Does Moss Live?
Like most other plants that aren’t annuals, moss doesn’t have a fixed lifespan.
The reason that we humans seem to have a limit on their years while plants don’t is due to aging. And in this case, age is not just a number. It’s actually the accumulation of damage to the structures and functions of molecules, cells, and organs.
The cause of aging in humans is due to a variety of factors, telomere shortening being one of the most notorious.
There’s ongoing research on why plants do not age, but one finding was that plants are able to regulate the telomerase enzyme, which is responsible for cancer in humans.
Plants are able to precisely regulate this enzyme to exactly compensate for telomere shortening, enabling them to prevent mutations from accumulating. These mutations play a major role in the deterioration of function over time and are why older people are more susceptible to cancer and other diseases.
If plants are able to prevent the accumulation of mutations and damage over time, then effectively it’s like they have eternal youth.
In theory, they should be able to live forever. But most mosses will eventually have their lives cut short due to external changes in their environment, like a heat wave, a drought, or a disgruntled property owner.
But this doesn’t necessarily mean that moss will go away forever. Newer generations of moss can take over once the conditions return back to normal.
Now that we’re on the subject of environmental changes, let’s get into how you can provide the right conditions to keep moss alive (or not).
How Do You Keep Moss Alive?
Keeping moss alive is almost like a paradox.
When you want to get rid of it, moss can be stubborn and resilient, continuing to grow back after several attempts to remove it. When you want to grow it, it can seem like it does nothing but wither away and die, despite bending over backward to cater to its needs.
In both cases, the outcome is entirely the result of the conditions where the moss is growing. As long as the conditions are just right, moss should be able to thrive.
Here’s what moss needs to stay alive:
- High moisture – As a primitive plant that lacks true roots, moss needs to absorb water directly through its leaves. This means that its surrounding environment must be abundant with water, such that it can be found on the surface, not hiding deep in the soil.
- Shade – As a plant that needs a lot of moisture, direct sunlight can easily dry it up and cause it to wither. Shade usually is a great place for moss to find the moisture it’s looking for and to get some shelter from the sun’s heat.
- Slightly acidic soil – acidic soil can provide moss with better access to nutrients like magnesium, phosphorus, and iron which can encourage it to grow.
As long as those ingredients are there, moss shouldn’t have much trouble surviving.
While there is some variation between individual moss species, they all generally have similar requirements. But if you are importing some moss to plant at home, it’s always good to check with your moss supplier if there are any specific needs that your particular moss has.
You don’t need to worry too much about cold weather freezing your moss to death. Most mosses are well adapted to handle colder winter temperatures, much more so than hotter temperatures.
If you’re curious to hear more about that, I get into the details in my guide to winter care for moss.
One of the most common reasons moss starts to turn brown and dry out is because it’s getting too much sunlight and not enough moisture.
This happens especially when a shade-producing structure is removed, exposing the previously sheltered moss to direct sunlight.
If you do find your moss starting to turn brown, you can check out this article where I walk you through how to troubleshoot any potential problems.
The opposite can be true too: moss can start showing up under the shade of growing plants or next to a newly built backyard shed.
If you want to give your newly planted moss the best chance to survive, ideally it should be planted somewhere in the shade or somewhere you can create some shade.
Planting it out in the open where it’s exposed to direct sunlight is less likely to turn out well for the moss.
If you must plant it out in the open, you need to be very diligent with checking your moss and watering it to ensure it doesn’t dry out. Watering once a day or multiple times per day may be necessary.
Besides planting moss outdoors, there’s also the option of growing moss in a terrarium. That’s a whole other topic that I cover in this article.
Does Moss Stay Green All Year?
Unlike annual flowering plants, moss is capable of staying green all year long, provided it has the right growing conditions.
As I mentioned before, the most common reason moss would be turning a shade of brown is if it’s getting too much sunlight and heat or not enough water. This especially happens during the spring and summer seasons when temperatures start to rise and the sun comes out in full force.
Since moss tends to better handle cooler temperatures, moss in the wild is usually more abundant during the fall and winter seasons, where temperatures are lower, rains come often, and the day is shorter.
Once the hotter spring and summer months come along, any moss patches that might have been barely making it by growing in less-shady areas may finally wither away due to the direct sunlight and high-temperature combination.
For this reason, if you’re planting moss of your own, it’s important to think about how the lighting conditions of your chosen planting spot will change throughout the seasons. In general, it’s better to plant where you’re certain there will be a good amount of shade year-round.
Any moss that has found a location that’s well-shaded and plentiful with moisture year-round should be perfectly capable of showing off its green colors all year.
How Long Can Moss Live Without Water?
I get it. We’re all busy. We don’t always have time to constantly check on our moss to see if it’s drying out. It would be nice to have an idea of how often it actually needs to be watered.
Moss should be watered anywhere from twice a week to every other week, depending on the level of shade, temperature, and humidity.
Since moss needs to stay moist, misting or watering it regularly becomes necessary if it’s hot and/or doesn’t rain too often where you live.
In fact, your watering schedule might need to kick into high gear if your region gets sudden heat waves, which seem to be getting more and more common these days.
Technically, there are reports by scientists of moss being “resurrected” from the dead after being completely bone-dry for over a hundred years. However, these cases seem to be specific to certain species of moss that likely have been carefully preserved and safely stored for research purposes.
In my experience, once a moss turns completely brown, it’s very unlikely that you’re going to be able to resurrect it with just a little water. So it’s best to not let it dry out to begin with.
For newly planted moss, it’s better to monitor it daily to see how it’s responding to its new environment, then slowly backing off as the moss establishes itself over the course of 1-2 months.
Although moss loves moisture, it’s still possible for moss to be overwatered. So don’t go overboard. If your moss is already pretty moist, there’s probably no need to give it additional water.
It’s always better to keep it simple and observe how your moss is doing moisture-wise and water accordingly. That’s much more manageable than giving your moss 14.5 ml of water per square inch at 6:45 AM every 2nd Monday of the month.
Does Moss Need Dirt To Survive?
Moss does not need dirt to survive, but removing it from its natural environment can be risky.
Moss doesn’t need dirt because it doesn’t have any roots that it can use to absorb water and nutrients from the soil.
Instead, moss has hair-like structures called rhizoids which only serve to anchor moss to its substrate. Although they might seem like tiny roots, rhizoids absorb little to no nutrients or water.
Without roots, there’s no need for soil. Moss is essentially just sitting snugly on the surface of the soil, but not actually taking in any resources from the soil itself. In fact, moss can actually grow on a variety of substrates in nature, including stone and wood.
So how does moss get its water and nutrients?
Moss is a non-vascular plant. What that means is moss doesn’t have any xylem or phloem, the “veins” that transport water and nutrients throughout a plant. Without xylem or phloem, there’s no way roots can be used to transport the goods up, into, and throughout the plant.
Instead, moss is a much “simpler” plant that absorbs water and nutrients directly through its leaves (technically known as phyllids) in a process called osmosis.
The phyllids are able to do this because they don’t have cuticle, the waxy substance that acts as a water-proof coating on most plant leaves. Without cuticle, water can freely pass through the cell wall and directly into the plant cells.
Since moss gets everything that it needs above ground, it doesn’t depend on soil for survival.
Can You Remove Moss and Replant It?
The short answer is yes, moss can be removed and replanted successfully if done correctly.
Although moss doesn’t need its original substrate to survive and you can remove moss and replant it, there’s a little disclaimer you should be aware of.
In my experience, the conditions moss needs to survive can be quite delicate. Making any drastic change to its environment (i.e. removing it from its original substrate and placing it somewhere else) will likely put the moss at risk.
In fact, I ran a little experiment of my own to put this theory to the test.
I harvested some moss and kept it in a ziploc bag to see how long it would live. I didn’t even open the bag to give it water.
I kept it on a table about 3-4 feet from a south-facing window. (In hindsight, this might not have been the best place to keep it).
What I found was that the moss seemed to be perfectly fine, at least for about 4 months. I could still see slight condensation on the bag where it was touching the moss, suggesting water was probably escaping from and being re-absorbed by the moss.
Eventually, it did start turning brown around month 5 once we started getting heatwaves without any AC to cool us down and it never went back.
What did I learn?
Moss does pretty well for itself without any proper substrate to attach itself to. However, careful consideration of its growing environment is required for it to survive in the long term.
So if you’re feeling extra paranoid, it certainly doesn’t hurt to reattach moss to the same substrate you found it if relocating some wild moss. But at the same time, it isn’t strictly necessary.
Hope you found that helpful!