North America Non-native Plant

Rattlebox

Botanical name: Crotalaria paulina

USDA symbol: CRPA22

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

Rattlebox (Crotalaria paulina): A Mysterious Member of the Legume Family If you’ve stumbled upon the name rattlebox in your gardening research, you might be wondering about this intriguingly named plant. Crotalaria paulina, commonly known as rattlebox, belongs to the diverse Crotalaria genus within the legume family. However, this particular species ...

Rattlebox (Crotalaria paulina): A Mysterious Member of the Legume Family

If you’ve stumbled upon the name rattlebox in your gardening research, you might be wondering about this intriguingly named plant. Crotalaria paulina, commonly known as rattlebox, belongs to the diverse Crotalaria genus within the legume family. However, this particular species presents something of a botanical puzzle for gardeners seeking reliable growing information.

What We Know About This Rattlebox

Crotalaria paulina gets its common name rattlebox from a characteristic shared with other members of its genus – the distinctive rattling sound made by mature seeds inside their dried pods. This family trait has earned various Crotalaria species the rattlebox moniker across different regions.

As a member of the legume family, this plant likely shares the nitrogen-fixing capabilities common to its relatives, potentially offering soil improvement benefits in garden settings.

The Challenge: Limited Documentation

Here’s where things get interesting (and a bit frustrating for gardeners): Crotalaria paulina appears to have very limited horticultural documentation available. This could mean several things:

  • It may be a lesser-known or regional species
  • The plant might be primarily of botanical rather than horticultural interest
  • There could be confusion with other Crotalaria species
  • It may have limited cultivation history

Geographic Distribution Mystery

The specific native range and geographic distribution of Crotalaria paulina remains unclear from available sources. Many Crotalaria species are found in tropical and subtropical regions worldwide, but without confirmed documentation, we cannot specify where this particular species naturally occurs.

Should You Grow Rattlebox?

Given the limited information available about Crotalaria paulina specifically, we’d recommend proceeding with caution. Here’s our honest gardening advice:

Before You Plant

  • Verify the plant identification with local botanical experts or extension services
  • Check with your local native plant society about this species
  • Confirm it’s not listed as invasive in your region
  • Consider well-documented native alternatives in the legume family

If You Decide to Proceed

Should you have confirmed sources and decide to grow this rattlebox, general Crotalaria growing principles might apply:

  • Most Crotalaria species prefer full sun
  • Well-draining soil is typically preferred
  • As legumes, they may not require heavy fertilization
  • Seeds often benefit from scarification before planting

Better-Documented Alternatives

If you’re drawn to the idea of growing a rattlebox or similar legume, consider researching these well-documented alternatives:

  • Native lupines (Lupinus species) for your region
  • Wild senna (Senna species) where native
  • Native clovers and other regional legumes

The Bottom Line

While Crotalaria paulina might sound intriguing, the lack of reliable growing information makes it a risky choice for most gardeners. Sometimes the most responsible approach is to admit when we simply don’t have enough information to make confident recommendations.

If you’re specifically interested in this plant, we’d encourage connecting with botanical gardens, universities, or specialist plant societies who might have more detailed knowledge about this particular rattlebox species.

Rattlebox

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 paulina Schrank - rattlebox

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