North America Native Plant

Cook’s Triteleia

Botanical name: Triteleia ixioides cookii

USDA symbol: TRIXC

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Brodiaea lutea (Lindl.) Morton var. cookii (Hoover) Munz (BRLUC)  âš˜  Triteleia ixioides (W.T. Aiton) Greene var. cookii Hoover (TRIXC2)   

Cook’s Triteleia: A Golden Gem for California Native Gardens If you’re looking to add a splash of sunshine to your California native garden, Cook’s triteleia (Triteleia ixioides cookii) might just be the perfect golden ticket. This charming little bulb produces clusters of bright yellow, star-shaped flowers that seem to capture ...

Rare plant alert!

Region: Conservation status by state

Status: S5T2: 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) ⚘ Secure: At very low or no risk of extinction in the jurisdiction due to a very extensive range, abundant populations or occurrences, with little to no concern from declines or threats. ⚘

Cook’s Triteleia: A Golden Gem for California Native Gardens

If you’re looking to add a splash of sunshine to your California native garden, Cook’s triteleia (Triteleia ixioides cookii) might just be the perfect golden ticket. This charming little bulb produces clusters of bright yellow, star-shaped flowers that seem to capture California’s golden light in botanical form.

What Makes Cook’s Triteleia Special?

Cook’s triteleia is a perennial forb – basically a non-woody flowering plant that comes back year after year. As a California native, it’s perfectly adapted to our Mediterranean climate and represents an authentic piece of the Golden State’s natural heritage. The plant goes by its botanical name Triteleia ixioides cookii and has been known by several scientific synonyms over the years, including Brodiaea lutea var. cookii.

Where Does Cook’s Triteleia Call Home?

This sunshine-colored beauty is endemic to California, making it a true Golden State original. You’ll find it naturally occurring in the Central Valley and surrounding foothills, where it has adapted to our unique climate patterns.

A Word About Conservation

Here’s something important to know: Cook’s triteleia has a conservation status that suggests it may be uncommon in the wild. If you’re interested in growing this special plant, please make sure you source your bulbs from reputable native plant nurseries that propagate their stock rather than wild-collecting. This helps protect wild populations while still allowing gardeners to enjoy this beautiful species.

Why Grow Cook’s Triteleia?

There are several compelling reasons to consider adding Cook’s triteleia to your garden:

  • Supports local pollinators with nectar-rich flowers
  • Perfectly adapted to California’s climate
  • Requires minimal water once established
  • Adds authentic native character to landscapes
  • Beautiful golden blooms brighten spring gardens
  • Helps preserve California’s botanical heritage

Garden Design and Landscaping Uses

Cook’s triteleia shines in naturalistic plantings and native plant gardens. It’s an excellent choice for rock gardens, Mediterranean-style landscapes, and drought-tolerant garden designs. The grass-like foliage and cheerful yellow flowers work beautifully in informal drifts or as accent plants among other California natives.

Growing Conditions and Care

Like many California natives, Cook’s triteleia thrives in conditions that might challenge other plants:

  • Sunlight: Full sun to partial shade
  • Soil: Well-draining soils are essential
  • Water: Minimal irrigation during growing season; dry summers preferred
  • Climate: Hardy in USDA zones 8-10

Planting and Care Tips

Successfully growing Cook’s triteleia is all about understanding its natural rhythm:

  • Plant bulbs in fall when temperatures begin to cool
  • Choose a location with excellent drainage to prevent bulb rot
  • Allow the plant to go dormant during hot summer months
  • Avoid overwatering, especially during dormancy
  • Mulch lightly to retain moisture during the growing season

Pollinator and Wildlife Benefits

The bright yellow flowers of Cook’s triteleia are more than just pretty faces – they’re valuable resources for California’s native pollinators. Bees and other beneficial insects appreciate the nectar these blooms provide during their spring flowering period.

Is Cook’s Triteleia Right for Your Garden?

Cook’s triteleia is an excellent choice if you:

  • Want to create an authentic California native garden
  • Are designing a drought-tolerant landscape
  • Appreciate subtle, naturalistic beauty
  • Want to support local pollinators
  • Are committed to sourcing plants responsibly

Remember, growing native plants like Cook’s triteleia isn’t just about creating a beautiful garden – it’s about participating in conservation and celebrating the unique natural heritage of California. Just make sure to source your plants responsibly to help protect wild populations of this special golden gem.

Cook’s Triteleia

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Liliidae

Order

Liliales

Family

Liliaceae Juss. - Lily family

Genus

Triteleia Douglas ex Lindl. - triteleia

Species

Triteleia ixioides (W.T. Aiton) Greene - prettyface

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