North America Non-native Plant

Tropical Sensitive Pea

Botanical name: Chamaecrista absus var. absus

USDA symbol: CHABA2

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

Synonyms: Cassia absus L. (CAAB16)   

Tropical Sensitive Pea: A Lesser-Known Garden Mystery If you’ve stumbled across the name tropical sensitive pea in your gardening research, you might be wondering what exactly this plant is and whether it deserves a spot in your garden. The truth is, Chamaecrista absus var. absus is something of an enigma ...

Tropical Sensitive Pea: A Lesser-Known Garden Mystery

If you’ve stumbled across the name tropical sensitive pea in your gardening research, you might be wondering what exactly this plant is and whether it deserves a spot in your garden. The truth is, Chamaecrista absus var. absus is something of an enigma in the gardening world – a plant that exists in botanical records but remains frustratingly elusive when it comes to practical growing information.

What’s in a Name?

Known botanically as Chamaecrista absus var. absus, this plant goes by the common name tropical sensitive pea. You might also see it listed under its synonym, Cassia absus L., in older botanical references. The name hints at its tropical origins and its relationship to the larger family of sensitive plants, though specific details about its native range remain unclear in current literature.

The Geographic Mystery

Here’s where things get a bit tricky – the exact native range and current distribution of this particular variety isn’t well-documented in accessible sources. This lack of clear geographic information makes it challenging for gardeners to determine whether this plant would be appropriate for their local ecosystem.

Garden Appeal and Growing Potential

Like other members of the Chamaecrista genus, the tropical sensitive pea likely produces small, cheerful yellow flowers that could add a delicate touch to garden spaces. However, without clear information about its growth habits, mature size, or preferred growing conditions, it’s difficult to recommend specific landscape uses or care requirements.

The Information Gap

Unfortunately, this is one of those plants where the available information is quite limited. We don’t have reliable data on:

  • Specific growing conditions and soil preferences
  • USDA hardiness zones
  • Mature plant size and growth rate
  • Invasive or beneficial status
  • Specific wildlife and pollinator benefits
  • Detailed planting and care instructions

A Better Path Forward

Given the uncertainty surrounding Chamaecrista absus var. absus, gardeners interested in sensitive peas might be better served exploring well-documented native alternatives. Consider researching Chamaecrista species that are confirmed native to your region, or look into other leguminous plants with similar characteristics that have established growing guides and known ecological benefits.

If you’re determined to learn more about this particular variety, reach out to local botanical gardens, native plant societies, or university extension services. They may have access to more specialized resources or can point you toward similar plants with better documentation.

The Bottom Line

While the tropical sensitive pea might sound intriguing, the lack of comprehensive growing information makes it a challenging choice for most gardeners. Rather than taking a gamble on an uncertain plant, focus your energy on well-researched native species that will provide known benefits to your local ecosystem while giving you the best chance of gardening success.

Sometimes the most responsible gardening choice is admitting when we need more information – and this mysterious little pea is definitely one of those cases.

Tropical Sensitive Pea

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

Chamaecrista (L.) Moench - sensitive pea

Species

Chamaecrista absus (L.) Irwin & Barneby - tropical sensitive pea

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