North America Native Plant

Arrowleaf Ragwort

Botanical name: Senecio triangularis

USDA symbol: SETR

Life cycle: perennial

Habit: subshrub

Native status: Native to Alaska âš˜ Native to Canada âš˜ Native to the lower 48 states  

Synonyms: Senecio gibbsonsii Greene (SEGI4)  âš˜  Senecio triangularis Hook. var. angustifolius G.N. Jones (SETRA)   

Arrowleaf Ragwort: A Bright Native Wildflower for Wet Spots If you’ve got a soggy corner of your garden that you’re not sure what to do with, let me introduce you to a cheerful native that actually loves wet feet. Arrowleaf ragwort (Senecio triangularis) is one of those delightful wildflowers that ...

Arrowleaf Ragwort: A Bright Native Wildflower for Wet Spots

If you’ve got a soggy corner of your garden that you’re not sure what to do with, let me introduce you to a cheerful native that actually loves wet feet. Arrowleaf ragwort (Senecio triangularis) is one of those delightful wildflowers that thrives where many other plants would throw in the towel and sulk.

What Makes Arrowleaf Ragwort Special?

This perennial herb gets its common name from its distinctive triangular leaves that look remarkably like arrowheads. But the real show-stopper is its explosion of bright yellow, daisy-like flowers that appear in dense, flat-topped clusters during mid to late summer. Standing 2-4 feet tall, this native beauty creates quite the statement when it’s in full bloom.

The plant spreads slowly through underground rhizomes, forming nice colonies over time without being aggressive about it. Think of it as the polite cousin in the plant world – it’ll expand its territory, but won’t bulldoze the neighbors.

Where Does It Come From?

Arrowleaf ragwort is a true western North American native, naturally found from Alaska all the way down to New Mexico. You’ll encounter it growing wild in states and provinces including Alberta, British Columbia, Alaska, California, Colorado, Idaho, Montana, Nevada, Oregon, Utah, Washington, and Wyoming. It’s particularly fond of mountain meadows, streambanks, and wetland edges.

Why Your Garden (and Local Wildlife) Will Love It

Here’s where this plant really shines – it’s like opening a diner for pollinators. The abundant yellow flowers are magnets for bees, butterflies, and other beneficial insects. The dense flower clusters provide an excellent landing platform and plenty of nectar to keep your garden’s pollinator population happy and well-fed.

From a design perspective, arrowleaf ragwort brings wonderful vertical structure to naturalized areas and provides that coveted bright summer color when many other plants are starting to look tired from the heat.

Perfect Garden Spots for Arrowleaf Ragwort

This plant is ideal for:

  • Rain gardens – It actually appreciates all that extra water
  • Bog or wetland gardens – Right at home with consistently moist conditions
  • Native plant landscapes – Authentic to western North American ecosystems
  • Naturalized areas – Looks perfectly at home in wild, informal settings
  • Mountain or alpine-style gardens – Mimics its natural high-elevation habitat

Growing Conditions That Make It Thrive

Arrowleaf ragwort has some specific preferences, but they’re pretty straightforward once you know what it wants:

Moisture: This is the big one – it needs consistently moist to wet soil. Think of it as the opposite of those drought-tolerant plants everyone talks about. If your soil dries out regularly, this isn’t your plant.

Light: It’s quite flexible here, doing well in full sun to partial shade. In hotter climates, some afternoon shade will keep it happier.

Soil: Prefers medium to fine-textured soils with good organic content. It’s not picky about pH, tolerating anywhere from 6.2 to 7.8, but appreciates fertile conditions.

Climate: Hardy in USDA zones 3-8, this plant can handle serious cold (down to -33°F!) but needs at least 145 frost-free days to complete its growing cycle.

Planting and Care Tips

Getting Started: Seeds are your best bet for propagation, and they’re readily available commercially. Spring planting works well, and with 500,000 seeds per pound, a little goes a long way!

Ongoing Care: Once established, arrowleaf ragwort is relatively low-maintenance. Keep the soil consistently moist (mulching helps), and consider dividing clumps every 3-4 years to prevent overcrowding. Deadheading spent flowers can extend the blooming period if you’re so inclined.

Be Patient: This plant has a moderate growth rate and what’s described as slow regrowth after disturbance, so don’t expect instant gratification. Good things take time!

A Few Things to Keep in Mind

While arrowleaf ragwort is generally well-behaved, it’s worth noting that like many plants in the Senecio family, it can contain compounds that may be harmful if consumed in large quantities. This is rarely an issue in garden settings, but it’s good to be aware of if you have curious pets or livestock.

The plant isn’t fire-resistant, so if you’re in a wildfire-prone area, consider its placement carefully in your defensible space planning.

The Bottom Line

If you’ve been struggling with what to plant in those perpetually moist spots in your garden, arrowleaf ragwort might just be your new best friend. It’s native, supports pollinators, provides gorgeous summer color, and actually wants to grow where the ground stays soggy. Sometimes the best plants are the ones that work with your garden’s natural conditions rather than fighting against them.

Just remember: wet feet good, dry feet bad. Keep that simple rule in mind, and you’ll have a thriving colony of these cheerful yellow beauties lighting up your landscape for years to come.

Wetland Status

The rule of seasoned gardeners and landscapers is to choose the "right plant for the right place" matching plants to their ideal growing conditions, so they'll thrive with less work and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection is. While tags list watering requirements, there's more to the story.

Knowing a plant's wetland status can simplify the process by revealing the interaction between plants, water, and soil. Surprisingly, many popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. Also, it helps you make smarter gardening choices and grow healthy plants with less care and feeding, saving you time, frustration, and money while producing an attractive garden with greater ecological benefits.

Regions
Status
Moisture Conditions

Alaska

FACW

Facultative Wetland - Plants with this status usually occurs in wetlands but may occur in non-wetlands

Arid West

FACW

Facultative Wetland - Plants with this status usually occurs in wetlands but may occur in non-wetlands

Great Plains

OBL

Obligate Wetland - Plants with this status almost always occurs in wetlands

Western Mountains, Valleys, and Coast

FACW

Facultative Wetland - Plants with this status usually occurs in wetlands but may occur in non-wetlands

Arrowleaf Ragwort

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Asteridae

Order

Asterales

Family

Asteraceae Bercht. & J. Presl - Aster family

Genus

Senecio L. - ragwort

Species

Senecio triangularis Hook. - arrowleaf ragwort

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