North America Native Plant

Trask’s Island Broom

Botanical name: Lotus dendroideus var. traskiae

USDA symbol: LODET

Life cycle: perennial

Habit: subshrub

Native status: Native to the lower 48 states  

Synonyms: Lotus scoparius (Nutt.) Ottley ssp. traskiae (Eastw. ex Noddin) P.H. Raven (LOSCT2)   

Trask’s Island Broom: A Rare California Native Worth Protecting Meet Trask’s island broom (Lotus dendroideus var. traskiae), a charming little shrub that’s as rare as it is beautiful. This petite perennial is one of California’s most exclusive native plants, found naturally in just one place on Earth—San Clemente Island. If ...

Rare plant alert!

Region: Conservation status by state

Status: S4T2: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000) ⚘ Apparently Secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the state or more than 10,000 individuals ⚘

Trask’s Island Broom: A Rare California Native Worth Protecting

Meet Trask’s island broom (Lotus dendroideus var. traskiae), a charming little shrub that’s as rare as it is beautiful. This petite perennial is one of California’s most exclusive native plants, found naturally in just one place on Earth—San Clemente Island. If you’re lucky enough to encounter this plant, you’re looking at a true botanical treasure.

What Makes Trask’s Island Broom Special?

This low-growing shrub typically stays under 1.5 feet tall and never exceeds 3 feet at maturity, making it perfect for gardeners who love plants with a compact, manageable size. Despite its diminutive stature, Trask’s island broom packs a punch with its delicate yellow pea-like flowers and silvery-green foliage that catches the light beautifully in coastal gardens.

As a member of the pea family, this native California plant produces the characteristic butterfly-shaped blooms that are absolutely irresistible to pollinators, particularly native bees and butterflies who have co-evolved with this species over thousands of years.

Where Does It Come From?

Trask’s island broom is endemic to California, specifically San Clemente Island off the coast of Southern California. This incredibly limited native range makes it one of the state’s most geographically restricted plants.

The Rarity Factor: What You Need to Know

Important conservation note: Trask’s island broom has a Global Conservation Status of S4T2, indicating it’s considered imperiled in the wild. This means if you’re interested in growing this remarkable native plant, you must source it responsibly from reputable native plant nurseries that propagate their stock rather than collecting from wild populations.

The rarity of this plant makes it extra special for native plant enthusiasts, but it also comes with the responsibility to help protect it rather than contribute to its decline.

Perfect Garden Situations

If you can find ethically sourced plants, Trask’s island broom shines in several garden settings:

  • Coastal and Mediterranean-style gardens
  • Drought-tolerant landscapes
  • Native California plant collections
  • Rock gardens and slopes needing erosion control
  • Pollinator gardens focused on native species

Growing Conditions and Care

Like many California natives, Trask’s island broom is surprisingly low-maintenance once established. Here’s what it needs to thrive:

Climate: Best suited for USDA hardiness zones 9-11, where it can handle the mild winters and warm, dry summers.

Light: Full sun exposure brings out the best in this plant, encouraging abundant flowering and compact growth.

Soil: Well-draining soil is absolutely essential. This island native can’t tolerate soggy roots and prefers sandy or rocky soils that mimic its natural habitat.

Water: Once established (usually after the first year), Trask’s island broom is quite drought tolerant. During establishment, provide regular water, then gradually reduce to occasional deep watering during extended dry periods.

Planting and Maintenance Tips

  • Plant in fall or early spring for best establishment
  • Space plants 2-3 feet apart to allow for mature spread
  • Mulch around plants with gravel or decomposed granite rather than organic mulch
  • Prune lightly after flowering to maintain shape
  • Avoid fertilizing—this native prefers lean soils

Supporting Pollinators and Wildlife

Despite its small size, Trask’s island broom punches above its weight when it comes to supporting local ecosystems. The bright yellow flowers provide nectar and pollen for native bees, while the plant’s structure offers shelter for small insects. By growing this rare native, you’re creating habitat that commercial plants simply can’t match.

Should You Grow Trask’s Island Broom?

If you’re a dedicated native plant gardener in Southern California with the right growing conditions and access to responsibly sourced plants, absolutely! This rare beauty offers unique character, low water needs, and unmatched ecological value. However, its rarity means it’s not a plant for casual gardeners or those unwilling to source it ethically.

Remember, growing rare natives like Trask’s island broom is both a privilege and a responsibility. By choosing this plant, you’re becoming a steward of California’s botanical heritage—and that’s pretty special indeed.

Trask’s Island Broom

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Rosidae

Order

Fabales

Family

Fabaceae Lindl. - Pea family

Genus

Lotus L. - trefoil

Species

Lotus dendroideus (Greene) Greene - island broom

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA