North America Native Plant

Cucumberleaf Sunflower

Botanical name: Helianthus debilis tardiflorus

USDA symbol: HEDET

Life cycle: annual

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Helianthus debilis Nutt. var. tardiflorus (Heiser) Cronquist (HEDET2)   

Cucumberleaf Sunflower: A Late-Blooming Native Gem for Southern Gardens If you’re looking for a native sunflower that marches to the beat of its own drum, meet the cucumberleaf sunflower (Helianthus debilis tardiflorus). This southeastern native is a bit of a rebel in the sunflower world – while most of its ...

Rare plant alert!

Region: Conservation status by state

Status: S5T3: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is 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. ⚘ 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. ⚘

Cucumberleaf Sunflower: A Late-Blooming Native Gem for Southern Gardens

If you’re looking for a native sunflower that marches to the beat of its own drum, meet the cucumberleaf sunflower (Helianthus debilis tardiflorus). This southeastern native is a bit of a rebel in the sunflower world – while most of its cousins are winding down for the season, this late bloomer is just getting started, bringing cheerful yellow flowers to your garden when many other plants are calling it quits.

What Makes Cucumberleaf Sunflower Special

The cucumberleaf sunflower is a herbaceous flowering plant native to the southeastern United States. As a forb, it lacks woody tissue and produces its energy through its soft stems and leaves rather than a woody trunk. This adaptable plant can behave as either an annual or perennial depending on growing conditions, making it a versatile addition to native plant gardens.

What sets this sunflower apart isn’t just its timing – it’s also perfectly adapted to coastal and southern growing conditions that might challenge other native plants.

Where It Calls Home

This sunny native has a relatively limited natural range, growing wild in Alabama, Florida, Georgia, and Mississippi. It’s particularly fond of the coastal plains and sandy soils of the Southeast, where it has evolved to thrive in conditions that might stress other plants.

A Note About Conservation

Before we dive into growing tips, it’s important to know that cucumberleaf sunflower has a conservation status that deserves our attention. If you’re interested in adding this plant to your garden, please source it responsibly from reputable native plant nurseries or seed suppliers. Avoid collecting from wild populations, as this can harm already limited natural stands.

Why Your Garden (and Local Wildlife) Will Love It

The cucumberleaf sunflower isn’t just a pretty face – it’s a pollinator magnet. Its bright yellow, daisy-like flowers provide nectar and pollen for bees, butterflies, and other beneficial insects during late summer and fall when many other food sources are becoming scarce. This timing makes it particularly valuable for migrating butterflies and late-season pollinators preparing for winter.

Birds also appreciate the seeds that follow the flowers, making this plant a double-win for wildlife gardeners.

Perfect Garden Roles

This adaptable sunflower shines in several garden settings:

  • Wildflower and prairie gardens
  • Coastal and seaside landscapes
  • Pollinator gardens
  • Naturalized areas
  • Native plant gardens
  • Low-maintenance landscape borders

Growing Conditions That Make It Happy

One of the best things about cucumberleaf sunflower is that it’s not particularly fussy. Here’s what it prefers:

  • Sunlight: Full sun is best – at least 6-8 hours of direct sunlight daily
  • Soil: Well-drained, sandy soils are ideal, though it adapts to various soil types
  • Water: Drought tolerant once established, but appreciates occasional watering during dry spells
  • Climate: Thrives in USDA hardiness zones 8-10

Its natural coastal habitat means it has some salt tolerance, making it a great choice for gardens near the ocean or in areas with salt spray.

Planting and Care Tips

Getting started with cucumberleaf sunflower is refreshingly straightforward:

  • Planting: Start from seed in spring after the last frost, or plant nursery-grown seedlings
  • Spacing: Give plants room to spread – they appreciate good air circulation
  • Maintenance: Very low maintenance once established
  • Fertilizer: Usually unnecessary – too much fertility can actually reduce flowering
  • Self-seeding: May self-seed in favorable conditions, providing natural garden renewal

The Bottom Line

Cucumberleaf sunflower offers southern gardeners a unique opportunity to support native ecosystems while enjoying beautiful late-season blooms. Its drought tolerance, wildlife benefits, and low-maintenance nature make it an excellent choice for gardeners who want maximum impact with minimal fuss.

Just remember to source your plants or seeds responsibly, and you’ll be rewarded with a native beauty that brings life to your garden when many other plants are preparing for winter dormancy. Sometimes the best things really do come to those who wait – and bloom fashionably late!

Cucumberleaf Sunflower

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

Helianthus L. - sunflower

Species

Helianthus debilis Nutt. - cucumberleaf sunflower

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