North America Native Plant

Sunset Lupine

Botanical name: Lupinus horizontalis

USDA symbol: LUHO3

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Sunset Lupine: A Rare California Native Worth Knowing If you’re passionate about native plants and love the idea of growing something truly special, sunset lupine (Lupinus horizontalis) might catch your attention. This annual California native is one of those plants that makes you appreciate the incredible diversity of our native ...

Rare plant alert!

Region: Conservation status by state

Status: S3?: Status is uncertain but is somewhere between the following rankings: Inexact rank: ⚘ Vulnerable: Either very rare and local throughout its range, found only in a restricted range (even if abundant at some locations), or factors are making it vulnerable to extinction. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals ⚘

Sunset Lupine: A Rare California Native Worth Knowing

If you’re passionate about native plants and love the idea of growing something truly special, sunset lupine (Lupinus horizontalis) might catch your attention. This annual California native is one of those plants that makes you appreciate the incredible diversity of our native flora, even if it’s not the easiest species to find or grow.

What Makes Sunset Lupine Special

Sunset lupine is a native forb, which means it’s a non-woody flowering plant that completes its life cycle in a single growing season. As an annual, it puts all its energy into producing flowers and seeds before winter arrives, making every growing season count.

This lupine species belongs to the larger family of lupines that gardeners often adore for their distinctive flower spikes and ability to fix nitrogen in the soil through their root nodules—a neat trick that actually improves soil fertility for neighboring plants.

Where You’ll Find It Growing Wild

Sunset lupine calls California home, where it has adapted to the state’s unique climate and growing conditions. As a California endemic, this species represents the kind of specialized native plant that makes the Golden State’s flora so remarkable.

The Reality Check: Rarity and Availability

Here’s where things get interesting (and a bit challenging): sunset lupine has a conservation status of S3?, which indicates some level of rarity or uncertain population status. This means you’re unlikely to find it at your local nursery, and that’s probably for the best.

If you’re determined to grow this species, it’s crucial to source seeds or plants only from reputable native plant suppliers who can guarantee the material was ethically and legally collected. Never collect seeds or plants from wild populations—this can harm already vulnerable populations.

Growing Challenges and Considerations

Unfortunately, specific cultivation information for Lupinus horizontalis is quite limited, which reflects its rarity and specialized nature. Like many California natives, it likely prefers:

  • Well-draining soils
  • Minimal summer water once established
  • Full sun to partial shade
  • Cool, moist conditions during germination and early growth

As an annual, you’ll need to allow plants to set seed naturally if you want them to return the following year, though success isn’t guaranteed without understanding its specific ecological requirements.

Better Alternatives for Most Gardeners

Unless you’re a serious native plant enthusiast with experience growing rare species, you might want to consider other California lupine species that are easier to obtain and grow successfully. Options like arroyo lupine (Lupinus succulentus) or dove lupine (Lupinus bicolor) can give you that lovely lupine look while being more garden-friendly and readily available from native plant sources.

The Bottom Line

Sunset lupine represents the fascinating diversity of California’s native plants, but it’s definitely not a beginner’s plant. Its rarity status means it deserves our protection and respect rather than casual cultivation attempts. If you do decide to try growing it, make sure you’re sourcing responsibly and have realistic expectations about success rates.

For most native plant gardeners, appreciating sunset lupine means supporting conservation efforts and choosing more readily available native alternatives that can provide similar ecological benefits without putting rare species at risk.

Sunset Lupine

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

Lupinus L. - lupine

Species

Lupinus horizontalis A. Heller - sunset lupine

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