Comarum palustre is known by many common names, including marsh cinquefoil, bog strawberry, purple marshwort, and purple marshlocks. This plant’s scientific name is actually a relatively new designation, as it used to be referred to as Potentilla palustris. Marsh cinquefoil is a flowering plant in the Rosaceae family, which includes a variety of plants, including true strawberries (Fragaria x ananassa).
Marsh cinquefoil has a circumboreal distribution, meaning that it can be found in Eurasia and North America. As one of its common names (bog strawberry) suggests, the flowers of comarum palustre plants do somewhat resemble standard strawberries that one might find in their kitchen.
Marsh cinquefoil produces dark red flowers with five petals surrounded by five-pointed sepals. Its leaves are oval-shaped and toothed along the edges. This plant is semi-aquatic, often growing with its roots underwater and much of the stem above it.
Facts, Benefits & Uses of Marsh Cinquefoil
Marsh cinquefoil is quite popular with pollinators, especially bees and hoverflies. In fact, it is on Britain’s Royal Horticultural Society’s “Plants for Pollinators” list. This plant is said to be virtually pest-free, meaning that wildlife such as deer will not destroy it.
Marsh cinquefoil’s creeping rhizomes help it to form colonies that can populate ponds and other water sources. These same rhizomes provide important habitats for aquatic invertebrates and various fish species, which can use the plant as shelter for spawning and safety from predators.
Interestingly, marsh cinquefoil has been studied for its potential to provide a variety of medicinal benefits. Its flowers can also be used to create a red dye that can be used on clothing.
Marsh Cinquefoil Growth, Hardiness & Climate
The growth rate of marsh cinquefoil is moderate, with plants reaching a full height of one to two feet. More significant than their height, however, is their spread. Marsh cinquefoil spreads through rhizomes and can form large clumps in ponds. Because of the high potential for spreading, take care when deciding where to plant marsh cinquefoil.
Marsh cinquefoil is hardy in zones 3-7, which allows it to grow year-round in its native zones. As a perennial, it should survive the winter in these areas. Blooming typically occurs from June to August, although some blooms may stick around into September. Marsh cinquefoil’s unique flowers will be present for the longest amount of time if the plant is given access to full sunlight and plenty of moisture.
How to Plant Marsh Cinquefoil In Ponds
A fairly easy plant, marsh cinquefoil is commonly grown in ponds. Due to this plant’s propensity for spreading into large colonies, it is worth considering planting in a container such as a pot or planting bag. This will not totally limit spreading however, as this plant also propagates through seeds. Marsh cinquefoil will be happy in the shallow water of a pond, and occasionally in simply moist soil. The maximum depth underwater is about ten inches for a mature plant.
How to Care For Marsh Cinquefoil
Marsh cinquefoil prefers very wet conditions and plentiful sunlight. Ideally, this species would be planted in the shallows of your pond where you won’t have to worry about providing additional water. The most important element in caring for this plant is ensuring that its soil doesn’t dry out. Partial shade will likely result in a plant that has fewer blossoms.
If you feel that your marsh cinquefoil plant is spreading more than you would like, you can dig up some of the rhizomes and divide the plant. Be sure to clean any trimmed or dropped detritus from this plant to maintain healthy water quality in your pond.
How to Winter Marsh Cinquefoil
Marsh cinquefoil is native to areas with significantly cold winters and is able to survive every season of the year up through hardiness zone 3. There is no need for any special treatment to prepare marsh cinquefoil for the winter in its native zones. Marsh cinquefoil is a perennial, so you should expect to see it in your pond for multiple years.
Is Marsh Cinquefoil Toxic, Poisonous or Invasive?
Marsh cinquefoil is native to a wide area and is technically invasive outside this range. It is not an extremely aggressive plant but will become widespread and form large colonies if allowed. As always, try to only use plants native to your specific region in your garden or pond. Regardless of where you live, it is a good idea to only plant marsh cinquefoil in some sort of container if you want to limit its spread through rhizomes. However, this plant does also spread through seeds.
Marsh cinquefoil exhibits no known toxicity and is therefore presumed safe for use in and around fish ponds. In fact, it’s a relatively common choice for ponds in many areas, such as the UK.
Is Marsh Cinquefoil Edible? Will Fish Eat it?
Marsh cinquefoil is likely edible to humans, and its leaves have occasionally been used as a medicinal tea to help with digestive issues. Animals such as deer tend to avoid this plant, likely because it is not especially tasty. Your fish may show interest in this plant for shelter and spawning habitat but are unlikely to try to eat it. If they do happen to nibble on the roots, your fish should not experience any negative effects.
Where to Buy Marsh Cinquefoil & Seeds? (UK & US)
Marsh cinquefoil is easily obtained at plant nurseries throughout its fairly widespread native range. Elsewhere in the world, you will likely have to order it online if you are set on growing it in your own pond or garden. As always, please take care when selecting plants that are not native to your area.
