Korean Clover: The Humble Ground Cover That’s Taking Root Across America
If you’ve ever wondered about those small, sprawling plants with tiny purple flowers dotting roadsides and abandoned lots, you might be looking at Korean clover (Kummerowia stipulacea). This unassuming annual has quietly made itself at home across much of the United States, and while it may not win any beauty contests, it has some interesting qualities that might surprise you.
What Exactly Is Korean Clover?
Korean clover, also known by its scientific name Kummerowia stipulacea (and formerly called Lespedeza stipulacea), is an annual forb that belongs to the legume family. Don’t let the clover name fool you – it’s not a true clover, but it does share that family’s ability to fix nitrogen in the soil. This low-growing plant typically reaches about 1.5 feet in height and spreads in a decumbent (sprawling) pattern across the ground.
Originally hailing from East Asia, Korean clover has established itself as a naturalized species throughout much of the eastern and central United States. It’s what botanists call a facultative upland plant, meaning it usually prefers drier ground but can tolerate some moisture.
Where You’ll Find Korean Clover
Korean clover has spread to an impressive 29 states, from Alabama to Wisconsin, and from Delaware to Texas. You’ll find it thriving in the Southeast, Midwest, Mid-Atlantic, and parts of the Great Plains. It’s particularly common in disturbed soils, roadsides, and areas where other vegetation struggles.
The Good, The Bad, and The Practical
So, should you consider Korean clover for your garden? Here’s the honest truth: it’s not going to dazzle anyone with its looks. The small purple flowers are barely noticeable, and the fine-textured green foliage won’t make any most beautiful garden lists. However, this humble plant has some practical benefits:
- **Nitrogen fixation**: Like other legumes, it improves soil fertility
- **Erosion control**: Its spreading growth habit helps stabilize soil
- **Low maintenance**: Once established, it requires minimal care
- **Wildlife value**: Provides food for various animals and birds, though not extensively
- **Rapid establishment**: Fast-growing with high seedling vigor
On the flip side, Korean clover isn’t native to North America, and while it’s not currently listed as invasive, any non-native plant carries some ecological considerations. It also has limited aesthetic appeal and provides only modest benefits to pollinators compared to native alternatives.
Growing Conditions and Care
If you’re thinking about Korean clover, you’ll be pleased to know it’s remarkably adaptable. This plant thrives in USDA hardiness zones 5-9 and tolerates a wide range of soil conditions:
- **Soil**: Adaptable to coarse, medium, and fine-textured soils
- **pH**: Prefers slightly acidic to neutral conditions (5.5-7.5)
- **Moisture**: Low water requirements with medium drought tolerance
- **Sunlight**: Needs full sun (shade intolerant)
- **Temperature**: Can handle temperatures as low as 6°F
Korean clover is active during spring and summer, with late spring blooms followed by abundant seed production. It requires at least 160 frost-free days and prefers areas receiving 30-65 inches of annual precipitation.
Planting and Propagation
Growing Korean clover is straightforward – it’s primarily grown from seed, which is routinely available commercially. With about 238,160 seeds per pound, a little goes a long way! The seeds spread rapidly, and seedlings show high vigor, meaning they establish quickly once conditions are right.
Plant seeds in spring after the last frost. Simply scatter them over prepared soil and lightly rake them in. No special stratification or treatment is needed. The plant will self-seed readily, so expect it to return year after year.
Wildlife and Ecological Value
While Korean clover won’t support wildlife like native plants do, it does provide some benefits. Large animals like deer may get 10-25% of their diet from Korean clover and occasionally use it for cover. Small mammals and terrestrial birds consume it less frequently (5-10% of diet) but rarely use it for shelter.
Consider Native Alternatives
Before choosing Korean clover, consider these native alternatives that provide similar benefits with greater ecological value:
- **Wild bergamot** (Monarda fistulosa) – Native pollinator magnet
- **Partridge pea** (Chamaecrista fasciculata) – Nitrogen-fixing native legume
- **Purple prairie clover** (Dalea purpurea) – Beautiful native with excellent wildlife value
- **Wild lupine** (Lupinus perennis) – Striking native nitrogen-fixer
The Bottom Line
Korean clover isn’t flashy, but it’s a reliable, low-maintenance option for areas where you need quick soil stabilization or nitrogen fixation. It’s particularly useful for rehabilitating poor soils or establishing ground cover in challenging conditions. However, given the wealth of beautiful native alternatives available, most gardeners will find better options for supporting local ecosystems while achieving their landscape goals.
If you do choose Korean clover, use it thoughtfully – perhaps in utility areas or as a temporary cover while establishing more permanent plantings. Just remember that every garden is an opportunity to support native wildlife, and there are plenty of gorgeous native plants that can do the job just as well, if not better.
