Trifolium willdenovii
tomcat clover
Western North America (British Columbia to Baja California)
SunFull Sun – Part Shade
WaterMedium
Overview
Trifolium willdenovii is a small annual clover in the pea family, growing 4-16 inches (10-40 cm) tall with slender, often branching stems. The leaves are divided into three narrow, toothed leaflets 0.4-1.2 inches (1-3 cm) long, typical of clovers. Flower heads are rounded, 0.4-0.8 inch (1-2 cm) across, and packed with small pea-type flowers that range from pink and lavender to purple, each head sitting above a fringed, cup-like bract. The plant grows in open grasslands, vernally moist flats, and disturbed ground from British Columbia south through California, often appearing in large seasonal stands after winter rains. As a legume it fixes nitrogen through root nodules and enriches the soils where it grows. It completes its life cycle in a single season, flowering in spring and dying back as soils dry in summer. Because it is an annual, it persists for only one season and must reseed to return, so it disappears from sites where the seed bank is exhausted or grazing is heavy. It is grazed by wildlife and livestock and supports native pollinators during its short bloom.
Native Range
Native to western North America, from British Columbia south through Washington, Oregon, and California into Baja California. It grows in open grasslands, vernal flats, meadows, and disturbed ground that stays moist into spring.Suggested Uses
Used in native wildflower mixes, meadow and grassland restoration, and seasonal pollinator plantings, and as a nitrogen-fixing part of cover-crop blends. It suits naturalistic plantings that follow the wet-winter, dry-summer cycle of its range.How to Identify
Appearance
Size & Dimensions
Height4" - 1'4"
Width/Spread4" - 10"
Bloom Information
Flowers in spring, mainly April and May in California, with bloom shifting earlier in warm lowlands and later at higher elevations. Flowering lasts several weeks and ends as soils dry in early summer. Plants set abundant seed before dying back.
Detailed Descriptions
Flower Description
pink to purpleFoliage Description
greenGrowing Conditions
Sun Requirements
Requires 6-10 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Water & Climate
Water Needs
Care & Maintenance
Care Guide
Trifolium willdenovii grows in full sun to light shade in soils that stay moist through winter and spring, from clay to loam. As a cool-season annual it germinates with fall and winter rains, grows through the wet months, and flowers before summer drought. It needs no fertilizer because it fixes its own nitrogen, and it tolerates seasonally wet ground better than many clovers. Sowing seed in fall on cleared soil establishes new stands. The plant dies back after seeding, leaving bare ground until the next germination. It tolerates a soil pH from about 5.5 to 7.5.Pruning
Pruning is not applicable to this annual clover. Leaving plants in place until seed matures keeps the stand self-sustaining. Mowing before seed set reduces the following seasons plants.✓ Toxicity
Non-toxicPlanting Guide
Planting Methods & Timing
Planting Method
direct sow
Direct Sow Timing
Fall, with the first autumn rains