North America Non-native Plant

Tropical Sensitive Pea

Botanical name: Chamaecrista absus var. meonandra

USDA symbol: CHABM

Life cycle: annual

Habit: forb

Native status: Non-native, reproduces and persists in the wild in the lower 48 states  

Synonyms: Cassia absus L. var. meonandra Irwin & Barneby (CAABM)   

Tropical Sensitive Pea: A Little-Known Desert Visitor If you’ve stumbled across the name tropical sensitive pea in your gardening research, you’ve discovered one of the more mysterious members of the legume family. This annual forb, scientifically known as Chamaecrista absus var. meonandra, is a non-native plant that has quietly established ...

Tropical Sensitive Pea: A Little-Known Desert Visitor

If you’ve stumbled across the name tropical sensitive pea in your gardening research, you’ve discovered one of the more mysterious members of the legume family. This annual forb, scientifically known as Chamaecrista absus var. meonandra, is a non-native plant that has quietly established itself in Arizona’s landscape.

What Is Tropical Sensitive Pea?

Tropical sensitive pea belongs to the Chamaecrista genus, a group of plants in the legume family known for their distinctive seed pods and often yellow flowers. As an annual forb, this plant completes its entire life cycle in one growing season, then relies on seeds to continue the next generation. Unlike woody shrubs or trees, it lacks significant woody tissue and maintains a herbaceous growth habit.

Where Does It Grow?

Currently documented in Arizona, this non-native species has managed to establish itself and reproduce without human intervention. As an introduced plant, it originally came from elsewhere but has found suitable conditions in the desert Southwest.

The Challenge of Limited Information

Here’s where things get interesting – and a bit frustrating for curious gardeners. Tropical sensitive pea appears to be one of those plants that flies under the radar. Information about its specific growing requirements, wildlife benefits, and garden performance is surprisingly scarce. This lack of documentation makes it difficult to recommend as a reliable garden choice.

Should You Grow It?

While there’s no evidence that tropical sensitive pea is invasive or harmful, the limited available information makes it a risky choice for most gardeners. Without clear guidance on growing conditions, expected size, or garden performance, you’d essentially be conducting your own experiment.

Better Alternatives: Native Arizona Options

Instead of gambling on this mysterious annual, consider these well-documented native Arizona legumes that offer similar characteristics with proven garden performance:

  • Desert Cassia (Senna covesii) – A reliable native with bright yellow flowers
  • Fairy Duster (Calliandra eriophylla) – Delicate, colorful blooms beloved by pollinators
  • Palo Verde (Parkinsonia florida) – Arizona’s state tree, perfect for larger spaces
  • Mesquite species (Prosopis spp.) – Drought-tolerant natives with wildlife benefits

The Bottom Line

While tropical sensitive pea might sound exotic and appealing, the lack of readily available growing information makes it a challenging choice for most gardeners. Your time and garden space are valuable – consider investing them in well-documented native species that will provide reliable beauty, support local wildlife, and thrive in your specific conditions.

Sometimes the most interesting plants are the ones we admire from afar while choosing their better-understood cousins for our gardens!

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