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Lesser Hop Trefoil
Trifolium dubium
Easy · Beginner friendlyAbout Lesser Hop Trefoil
Little Hop Clover or Small Hop Clover is a small European annual clover naturalized throughout US lawns, roadsides, and meadows, with trifoliate leaves and tiny yellow flower heads that fade to brown papery seed heads. Growing only 4 to 10 inches, it behaves weedily in lawns and gardens. Often identified as the true original shamrock of Ireland alongside or instead of white clover, though the tradition is mixed.
- Groundcover
- Pollinator-friendly
- Drought-tolerant
How to care for Lesser Hop Trefoil
Watering
- Springevery 7 days
- Summerevery 5 days
- Fallevery 10 days
- Winterevery 21 days
Soil · Well-draining
- Top dressingPine bark mulch10%
- Main mixPotting soil + perlite 2:170%
- DrainageLECA / gravel20%
Never skip the drainage layer — standing water is the top cause of root rot.
FERTILIZER
This plant needs little to no feeding.
At a Glance
- NativeEurope, Western Asia, Africa
- Height0.5–1 ft (0.2–0.3 m)
- Spread0.5–1 ft (0.2–0.3 m)
- Flower colorYellow
- Foliage colorGreen
- Fruit colorBrown
- SoilLoamy, Well-drained
- LocationsYard
Bloom time
BLOOM CYCLE
Peak bloom
May–Aug
Tiny yellow flower heads May through August
Fragrance
LIGHT FRAGRANCE
The flowers have a lightly honey-scented scent.
Toxicity
No toxicity has been reported for this plant. Still, it is wise to keep pets from chewing on any houseplant.
Educational information, not medical or veterinary advice. If exposure is suspected, contact a doctor or veterinarian.
DISTRIBUTION
- Native
- Introduced
- Europe
- Western Asia
- Africa
History
Trifolium dubium grows in meadows, lawns, and disturbed ground across Europe, North Africa, and western Asia, and has naturalized in North America and Australasia. The English botanist John Sibthorp described it in 1794. Though several small Trifolium and Medicago species compete for the title of the 'true' Irish shamrock, a 1988 survey by naturalist Charles Nelson at the National Botanic Gardens of Ireland identified T. dubium as the species sold by 46% of Irish market traders as the traditional Saint Patrick's Day shamrock; T. repens came second.
Its tiny yellow flower heads distinguish it from white-flowered T. repens. Though small, it contributes to nitrogen fixation in pastures and lawns. Modern Irish botanical merchandise and commemorative St. Patrick's Day displays most often use T. Now one of the most common lawn weeds across the US. dubium as the symbol plant.
Symbolism & meaning
What It Symbolizes
Lesser Hop Trefoil carries Irish heritage — botanists generally agree it is the true original shamrock, the small yellow-flowered clover most likely held up by St. Patrick. Paired with modest tenacity, it persists in lawns where ordinary grass struggles, quietly outlasting the mower. To find it underfoot is to be standing, however briefly, on a small piece of contested folkloric soil.
- Irish heritage — likely the true original shamrock
- Modest tenacity — persists in lawns where grass struggles
Where the Name Comes From
'dubium' from Latin means doubtful, for the historically uncertain taxonomy of small yellow clovers.
Uses & Fun Facts
- Often cited as the original Irish shamrock of Saint Patrick
Related plants
More Trifolium plants
Narrow-leaved CloverTrifolium angustifolium
Rabbitfoot CloverTrifolium arvense
Large Hop CloverTrifolium aureum
Hop TrefoilTrifolium campestre
Plants with similar care
Chinese AbeliaAbelia chinensis
Fragrant AbeliaAbelia mosanensis
Large-Flowered AbeliaAbelia uniflora
Glossy AbeliaAbelia x grandiflora
Frequently asked questions
How often should I water Lesser Hop Trefoil?
In summer, water about every 5 days; in winter, about every 21 days. Adjust for heat, pot size and drainage.
How much light does Lesser Hop Trefoil need?
Full sun: 6+ hrs direct. Watch the leaves — scorching or stretching means the light needs adjusting.
Is Lesser Hop Trefoil toxic to cats or dogs?
No toxicity has been reported for this plant. Still, it is wise to keep pets from chewing on any houseplant. Educational information, not medical or veterinary advice. If exposure is suspected, contact a doctor or veterinarian.
Is Lesser Hop Trefoil easy to grow?
Yes — it is considered an easy, beginner-friendly plant.
When does Lesser Hop Trefoil bloom?
It typically blooms May–Aug in the Northern Hemisphere.
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