North America Non-native Plant

Crotalaria Argyrolobioides

Botanical name: Crotalaria argyrolobioides

USDA symbol: CRAR15

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

Crotalaria argyrolobioides: A Mysterious Member of the Rattlebox Family If you’ve stumbled upon the name Crotalaria argyrolobioides in your botanical wanderings, you’re not alone in scratching your head. This lesser-known member of the Crotalaria genus (commonly called rattleboxes) is something of an enigma in the gardening world – and for ...

Crotalaria argyrolobioides: A Mysterious Member of the Rattlebox Family

If you’ve stumbled upon the name Crotalaria argyrolobioides in your botanical wanderings, you’re not alone in scratching your head. This lesser-known member of the Crotalaria genus (commonly called rattleboxes) is something of an enigma in the gardening world – and for good reason.

The Challenge of the Unknown

Here’s the thing about Crotalaria argyrolobioides: it’s one of those plants that botanists know exists, but gardeners rarely encounter. Unlike its more famous cousins in the Crotalaria family, this particular species hasn’t made its way into mainstream horticulture, leaving us with more questions than answers.

What We Do Know

As a member of the Crotalaria genus, this plant is part of the legume family (Fabaceae). The genus name Crotalaria comes from the Greek word krotalon, meaning rattle – a reference to the rattling sound made by seeds in the dried pods of many species in this group.

Geographic Distribution and Native Status

Unfortunately, specific information about where Crotalaria argyrolobioides naturally occurs is not readily available in standard horticultural references. This lack of information suggests it may be either extremely rare, limited to a very specific geographic region, or possibly under-studied.

Should You Try to Grow It?

Here’s where things get tricky. Without clear information about this plant’s:

  • Native range and conservation status
  • Growing requirements
  • Hardiness zones
  • Potential invasiveness
  • Availability in the nursery trade

It’s difficult to recommend whether or not you should add it to your garden. If you’re interested in rare or unusual plants, this one certainly fits the bill – but proceed with caution.

A Better Alternative: Known Crotalaria Species

If you’re drawn to the Crotalaria genus, consider exploring better-documented species instead. Many Crotalaria species offer:

  • Bright yellow, pea-like flowers
  • Nitrogen-fixing capabilities that benefit soil
  • Interesting seed pods that rattle when dry
  • Pollinator appeal

Just be sure to research any Crotalaria species thoroughly, as some can be weedy or even toxic to livestock.

The Bottom Line

Crotalaria argyrolobioides remains a botanical mystery for home gardeners. Until more information becomes available about its characteristics, growing requirements, and conservation status, it’s best to admire it from afar and focus on well-documented native plants that you know will thrive in your garden.

If you’re a serious plant collector or researcher who encounters this species, consider contributing to our collective knowledge by documenting your observations. Every bit of information helps fill in the gaps for these lesser-known botanical treasures.

Crotalaria Argyrolobioides

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 argyrolobioides Baker

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