Chinese marshflower, also known as creeping mazus and Miquel’s mazus, is an incredibly hardy, creeping groundcover plant. Though it may look dainty with its small, soft lime-green leaves and pretty purple to white flowers, Chinese marshflower bounces back readily from disturbances like flooding, moderate drought, being walked on, and can even be mowed over. Originally hailing from the Himalayan mountains of China, this fast-growing plant can now be found on most continents, including portions of Europe and North America where it is not native, and ranges from being considered naturalized to downright invasive depending on location and environmental conditions.
Originally placed in the family Scrophareliaceae (the figwort family) in the early 1900s, the evolution of improved understanding of morphology and plant functions placed Chinese marshflower in Phrymaceae (the lopseed family) somewhere in the mid-1900s.
Decades later, it was moved to the newer Mazaceae (Mazus) family in 2011 upon greatly improved genetic testing that is able to more accurately place plants than just examining morphology alone. Mazus miquelii was formerly known as Mazus reptans; this can be confusing, as many non-reputable sources list them as separate species, but genetic testing has revealed them to be the same. Unfortunately, it seems that some nurseries in California began referring to the plant as “reptans” in the 1990s when the plant was gaining popularity, perhaps in an effort to try to distinguish their plants from others, and it stuck. Botanists are still trying to stop the spread of misinformation.
Facts, Benefits & Uses of Chinese Marshflower
Chinese marshflower has dense, spreading roots that help to hold soil in place. Its closely packed, mat-forming stems and leaves provide habitat and cover for small mammals, insects, lizards, frogs, and the like, depending on where you live. In turn, these can provide food for the likes of raptors like hawks and owls, smaller birds that enjoy insects, and others like snakes or foxes. Again, this depends on where you live and the species that can be found nearby. Additionally, whether you live within the plant’s native range or not will factor in, as most organisms are most familiar with, understandably, their native species and less likely to take up residence in an unfamiliar plant. Additionally, its small, vibrant blooms can draw in a variety of pollinators.
Chinese Marshflower Growth, Hardiness & Climate
Chinese marshflower is a quite fast grower, typically only reaching a height of 2 inches (though it has been known to grow up to 4 inches) and spread of about one foot in diameter per plant, with plants often intertwining to form thick, creeping beds. These plants prefer to grow in full sunlight and will show their environmental satisfaction by sprouting their characteristic two-lipped, typically lilac-hued flowers. Blooming often occurs from May through July, though this time can be extended if you live in a more temperate location.
If you wish to slow the growth of creeping mazus, you can plant it in full shade; it prefers full to partial sun, which will result in faster growth. Its primary hardiness zones are 5 through 11 (the higher range of which can result in evergreen plants), but it can be grown as low as hardiness zone 3. Growing in the lower hardiness zones results in a perennial plant (or sometimes annual, if conditions are harsh enough), which can be a boon if you don’t wish it to spread as readily.
How to Plant Chinese Marshflower In Ponds
Chinese marshflower is most readily grown from cuttings of already established plants or purchased from nurseries as such. To plant, simply cover the roots in damp (but not saturated) soil in either full sun or partial shade. Ideally, planting should occur in Spring. If planting more than one, place them a foot (30.5 cm) or so apart to allow for plenty of growth room. If you desire to slow their spread, you can plant them as close as 6 inches (15.24 cm) apart. Do note that Chinese marshflower can have aggressive, spreading roots and stems, and is known to overtake other groundcover plants. Only place in bare areas, such as between paving stones or along pathways, else this plant could choke out other groundcovers.
How to Care For Chinese Marshflower
Not a particularly picky plant, creeping mazus really just needs moist, but well-draining soil, and at least partial sunlight to really thrive. As mentioned previously, you can grow this plant in full shade to help slow spread, but this is likely to result in fewer flowers. To help control growth, it’s recommended to dig up portions of the plant and trim it (roots included). You can choose to replant these cuttings if you wish to grow Chinese marshflower in new areas or toss them in the trash to reduce the plant’s biomass. This will not kill the plant, as it’s quite hardy and can even be mowed over! Do not place in a compost heap, as it’s quite possible that creeping mazus will just take hold there instead.
Chinese marshflower can tolerate some flooding, but prefers to simply be in moist soil as opposed to having completely wet feet. As such, plant around paths or along the edge of your pond, but not directly in it. It’s worth noting that some studies have found Chinese marshflower to be prone to root rot if too saturated, as well as several necrotic viruses that have the potential to spread to other ornamental plants. Prior to this study, these viruses were only known to affect privets and impatiens.
How to Winter Chinese Marshflower
Chinese marshflower prefers locations with mild winters without extended periods of freezing temperatures but can overwinter just fine in hardiness zones above 5. Beneath this, Chinese marshflower may be able to survive a couple of winters but is likely to die out after a year or two. You can either allow creeping mazus to die out each winter if you live in a cold climate (which would help prevent its overgrowth), you can try covering the tops of the plants with several inches of moist mulch to act as an insulating layer, or you can transfer them indoors for winter to a bright, sunny, warm location.
Is Chinese Marshflower Toxic, Poisonous or Invasive?
In short, any plant grown outside of its historically native range has the potential to become invasive. With that being said, since Chinese marshflower can be quite a fast and aggressive grower, it is often considered invasive outside of its Asian homeland. We always encourage readers to utilize plants that are native to their particular region. If you live in Europe, a similarly trailing, water-tolerant groundcover plant that we recommend is creeping jenny. If you live in the US, consider giving lemon bacopa a try. To learn more, you can find our guide to growing creeping jenny here, and our guide to growing lemon bacopa here.
There are no known reports of Chinese marshflower being toxic. In fact, some indigenous peoples in India historically used the boiled-down roots of the plants to treat a variety of stomach ailments and pains. Regardless, we do not advise eating or using any plant medicinally unless you are very familiar with it.
Is Chinese Marshflower Edible? Will Fish Eat it?
Chinese marshflower is technically edible, and shouldn’t harm your fish should they choose to nibble on it. However, since this plant doesn’t prefer to grow directly in water, there is little concern regarding your fish even having access to it. As always, if any leaves, flowers, and so on should fall into the water, we advise cleaning them out of the pond to help maintain water quality and fish health.
Where to Buy Chinese Marshflower & Seeds? (UK & US)
A fairly popular groundcover plant, Chinese marshflower is readily available in both the UK and the US via both in-person nurseries as well as online outlets. Before purchasing, please make sure that the plant is not invasive in your area, and is legal to have.
