North America Non-native Plant

Crotalaria Senegalensis

Botanical name: Crotalaria senegalensis

USDA symbol: CRSE12

Native status: Not native but doesn't reproduce and persist in the wild

Synonyms: Crotalaria maxillaris Klotzsch (CRMA22)   

Crotalaria senegalensis: A Lesser-Known Legume for Adventurous Gardeners If you’re the type of gardener who enjoys growing something a little different, Crotalaria senegalensis might just pique your interest. This member of the pea family may not have a catchy common name that rolls off the tongue, but it certainly has ...

Crotalaria senegalensis: A Lesser-Known Legume for Adventurous Gardeners

If you’re the type of gardener who enjoys growing something a little different, Crotalaria senegalensis might just pique your interest. This member of the pea family may not have a catchy common name that rolls off the tongue, but it certainly has characteristics that make it worth considering for the right garden setting.

What Exactly Is Crotalaria senegalensis?

Crotalaria senegalensis is a leguminous plant that hails from the warm regions of West and Central Africa, particularly around Senegal (hence the species name). You might also see it listed under its botanical synonym, Crotalaria maxillaris. Like other members of the Crotalaria genus, this plant has the superpower of fixing nitrogen in the soil, making it a friend to neighboring plants and gardeners alike.

Where Does It Come From?

This plant calls the tropical and subtropical regions of Africa home, thriving in the warm climates of Senegal and surrounding West African countries. It’s adapted to areas with distinct wet and dry seasons, which gives us clues about how to grow it successfully.

Garden Appeal and Characteristics

While Crotalaria senegalensis may not win any beauty contests, it has a understated charm that grows on you. The plant produces cheerful yellow flowers that are typical of the pea family – small but bright, and attractive to pollinators. The upright growth habit and green foliage provide a nice backdrop for showier plants, making it more of a supporting actor than a leading lady in the garden theater.

Why Grow (or Not Grow) Crotalaria senegalensis?

Reasons you might want to plant it:

  • Nitrogen fixation improves soil fertility naturally
  • Attracts beneficial pollinators like bees
  • Drought tolerant once established
  • Easy to grow from seed with minimal fuss
  • Interesting conversation starter for plant enthusiasts

Reasons you might want to skip it:

  • Not native to North America, so it won’t support local wildlife ecosystems as well as native alternatives
  • Limited availability – you might have trouble finding seeds or plants
  • Better suited for warmer climates (USDA zones 9-11)
  • May self-seed, though not considered invasive

Growing Conditions and Care

If you decide to give Crotalaria senegalensis a try, you’ll find it refreshingly low-maintenance. This plant appreciates full sun and well-draining soil – think of its African origins where the soil doesn’t stay soggy. Once established, it’s quite drought tolerant, though it will look happier with occasional watering during dry spells.

The plant thrives in USDA hardiness zones 9-11, where it can behave as a perennial. In cooler zones, treat it as an annual and enjoy it for a single growing season. It’s not fussy about soil types but does appreciate good drainage.

Planting and Care Tips

  • Start from seed – it’s the most reliable method
  • Sow seeds directly in the garden after the last frost date
  • Barely cover seeds with soil, as they need some light to germinate
  • Water regularly until established, then reduce frequency
  • No fertilizer needed – remember, this plant makes its own nitrogen!
  • Deadhead spent flowers if you don’t want it to self-seed

Garden Design Ideas

Crotalaria senegalensis works well in naturalized areas, wildlife gardens, or as part of a world garden where you’re showcasing plants from different continents. It’s not flashy enough for formal borders but could work nicely in cottage-style gardens or as a filler plant in mixed beds.

Consider Native Alternatives

While there’s nothing wrong with growing Crotalaria senegalensis, consider exploring native legumes that will provide similar benefits while supporting local wildlife. Wild senna (Senna hebecarpa), partridge pea (Chamaecrista fasciculata), or wild lupine (Lupinus perennis) are just a few native options that offer nitrogen fixation, pollinator appeal, and better ecological value for North American gardens.

The Bottom Line

Crotalaria senegalensis is one of those plants that appeals to gardeners who enjoy trying something new and different. It’s not going to be the star of your garden, but it can play a useful supporting role while satisfying your curiosity about plants from distant places. Just remember that when it comes to supporting local wildlife and ecosystems, native plants are always the better choice.

Crotalaria Senegalensis

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

Crotalaria L. - rattlebox

Species

Crotalaria senegalensis (Pers.) Bacle ex DC.

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