Willow Moss Growing, Planting, Facts & Care (Fontinalis antipyretica)
Willow moss, also known as greater water moss and common water moss, is a species of submerged aquatic moss. This species is in the class Bryopsida, which consists of over 11,000 moss species across the globe. The appearance of Fontinalis antipyretica is often compared to willow trees, which is what led to its common name “willow moss.” Interestingly, its Latin name antipyretica translates to “fireproof” or “fire stopper.” The reason for this unique name is that in several Nordic countries, this species was once used as fire and smoke insulation between the chimney and walls.
Willow moss is quite widespread and can be found growing in fresh water in Europe, Asia, Africa, and North America. This species is a true aquatic moss, which grows entirely underwater and does not produce flowers. Willow moss is often compared to Java moss, and the two species are frequently confused with each other. However, willow moss has larger and more defined leaves, and tends to be a deeper green color.
Facts, Benefits & Uses of Willow Moss
Willow moss provides important habitat and protection for fish eggs, adult fish, and shrimp fry. Many underwater invertebrates benefit greatly from the presence of willow moss, as well. Mayfly, caddisfly, and stonefly nymphs and larvae cling to its underwater fronds, and chironomid larvae shelter in the bases of its leaves. Newts, as well as damselfly and dragonfly larvae, also benefit from willow moss cover and its oxygenating properties. These aquatic insects in turn provide very nutrient-rich food sources for fish, be they wild fish like bass or domesticated ones like koi.
Another important asset of willow moss is that it is an excellent oxygenating plant. In addition, researchers have found that Fontinalis antipyretica is good at absorbing heavy metals such as cadmium and zinc.
This is a versatile plant and can be found in both still and flowing water. It is a popular choice for both ponds and indoor freshwater aquariums. Willow moss attaches to rocks in fast-flowing water and can attach to pond substrate, driftwood, or simply form floating clumps in more calm waters, making it ideal for just about any freshwater environment.
Willow Moss Growth, Hardiness & Climate
Willow moss has a moderate growth rate and is often recommended as an aquatic plant for beginners. Keep in mind that this plant does not emerge above the surface of water, so it is not generally an ornamental option for ponds, though in clearer ponds you will be able to see it through the water. However, your fish will appreciate the addition of willow moss to their pond, as it is a valuable contributor to underwater ecosystems. Many aquarium owners choose willow moss for both its attractive foliage and its benefits for fish, amphibians, and aquatic invertebrates.
Willow moss often reproduces through propagation of detached pieces of the plant. It also can reproduce through stolons, which are creeping plant runners that take root and sprout new stems. Willow moss can sometimes reproduce through spores, but this is somewhat rare, as the plant does not frequently produce sporangia.
How to Plant Willow Moss In Ponds
An easy way to establish willow moss is to tie it to driftwood or stone underwater. It will quickly attach to other surfaces like rocks and substrate, and will likely spread on its own. Many nurseries that provide willow moss will sell it in weighted bunches, which help it to settle in one place. It also is an option to simply allow willow moss to float in still water, and allow it to “choose” its own location. You can often establish willow moss with cuttings from an established plant.
How to Care For Willow Moss
Willow moss requires minimal care, so it is a great option for a low-maintenance pond or aquarium addition. This plant is considered to be quite hardy and requires very little specific care from gardeners. Willow moss grows best in moderate to cool temperatures; for warm ponds and aquariums, many gardeners transition to java moss. Willow moss prefers slightly acidic water but can be found up to pH levels of 7.5-8 at times. Willow moss can tolerate some short periods of drying out, but this is not ideal.
How to Winter Willow Moss
There is no need for any special treatment to prepare willow moss for the winter in its native zones. Willow moss is a perennial, so you should be able to see it in your pond for multiple years as long as it is provided with the proper conditions.
Is Willow Moss Toxic, Poisonous or Invasive?
Willow moss is not considered to be invasive and is already quite widespread globally. It is not an aggressive plant and is not known to overtake areas. However, it is certainly able to spread, especially through establishment from broken-off pieces of the plant which can travel through water. Willow moss is also not known to be toxic, and therefore would be a safe addition to your pond for fish and other critters.
Is Willow Moss Edible? Will Fish Eat it?
There is no evidence of humans ever eating willow moss, so we do not know if it is edible. Some freshwater shrimp and snails do eat this plant. Pond fish will most likely be interested in willow moss for the shelter it provides rather than as food. This is a common aquatic plant, and should be perfectly safe for your fish if they do decide to taste it.
Where to Buy Willow Moss & Seeds? (UK & US)
Willow moss is quite common and is easily obtained from aquatic plant nurseries essentially worldwide. You may have to order it online or request a special order from a standard plant nursery, as they may not necessarily carry aquatic plants in stock. You may also be able to find willow moss at an aquarium supply store, as it is a common aquarium plant. As always, take care when growing a new plant in your area. Be sure to only plant willow moss in your own private pond, not in wild ponds or streams.