North America Non-native Plant

Prosopis Humilis

Botanical name: Prosopis humilis

USDA symbol: PRHU3

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

Prosopis humilis: A Plant to Avoid in Your Garden When it comes to gardening, not every plant deserves a spot in your landscape—and Prosopis humilis is definitely one to steer clear of. While this South American shrub might seem like an interesting addition to drought-tolerant gardens, there’s a very important ...

Noxious plant alert!

Prosopis humilis: A Plant to Avoid in Your Garden

When it comes to gardening, not every plant deserves a spot in your landscape—and Prosopis humilis is definitely one to steer clear of. While this South American shrub might seem like an interesting addition to drought-tolerant gardens, there’s a very important reason why you shouldn’t plant it.

What is Prosopis humilis?

Prosopis humilis is a small shrub native to South America, particularly found in Argentina, Paraguay, and southern Brazil. This member of the legume family produces compound leaves and small, yellow flower spikes that might catch your eye. However, looks can be deceiving when it comes to this particular plant.

Why You Should NOT Plant Prosopis humilis

Here’s the deal-breaker: Prosopis humilis is classified as a noxious weed in the United States. This means it’s not just unwelcome—it’s actually prohibited in many areas due to its aggressive spreading behavior and negative impact on native ecosystems.

Noxious weeds like Prosopis humilis can:

  • Outcompete native plants for resources
  • Alter soil chemistry and ecosystem balance
  • Reduce biodiversity in natural areas
  • Be extremely difficult to remove once established

Growing Characteristics (For Identification Purposes Only)

Understanding how this plant grows can help you identify and avoid it:

  • Hardiness: Thrives in USDA zones 9-11
  • Growing conditions: Extremely drought-tolerant, prefers full sun and sandy soils
  • Appearance: Small shrub with compound leaves and yellow flower clusters
  • Pollinator activity: While it does attract bees, this doesn’t outweigh its negative impacts

Better Native Alternatives

Instead of risking the problems that come with Prosopis humilis, consider these fantastic native alternatives that offer similar drought tolerance and wildlife benefits:

  • Desert Willow (Chilopsis linearis): Beautiful flowering shrub perfect for dry climates
  • Palo Verde species: Stunning native trees with yellow blooms
  • Native mesquite species: Look for locally native Prosopis species that won’t cause ecological harm
  • Acacia species: Choose native acacias for similar form and drought tolerance

The Bottom Line

While Prosopis humilis might survive in challenging conditions and even provide some wildlife benefits, its status as a noxious weed makes it a no-go for responsible gardeners. The potential ecological damage simply isn’t worth the risk, especially when there are so many wonderful native alternatives available.

Remember, the best gardens work with nature, not against it. By choosing plants that belong in your region, you’ll create a landscape that’s both beautiful and beneficial to local wildlife—without the headaches that come with invasive species management.

Prosopis Humilis

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

Prosopis L. - mesquite

Species

Prosopis humilis Gillies ex Hook. & Arn.

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