North America Non-native Plant

Smut Grass

Botanical name: Sporobolus indicus var. major

USDA symbol: SPINM

Habit: grass

Native status: Non-native, reproduces and persists in the wild in Pacific Basin excluding Hawaii  

Synonyms: Sporobolus fertilis (Steud.) Clayton (SPFE3)   

Smut Grass: A Tropical Grass for Pacific Gardens If you’re gardening in the tropical Pacific and looking for a hardy, low-maintenance grass, you might have come across smut grass (Sporobolus indicus var. major). This adaptable grass has made itself at home in places like Guam and Palau, where it thrives ...

Smut Grass: A Tropical Grass for Pacific Gardens

If you’re gardening in the tropical Pacific and looking for a hardy, low-maintenance grass, you might have come across smut grass (Sporobolus indicus var. major). This adaptable grass has made itself at home in places like Guam and Palau, where it thrives in the warm, humid climate. But before you decide whether to welcome it into your garden, let’s explore what makes this grass tick.

What Exactly Is Smut Grass?

Smut grass, scientifically known as Sporobolus indicus var. major, is a non-native grass that has established itself in the Pacific Basin. You might also see it listed under its synonym, Sporobolus fertilis. This grass belongs to the large family of grasses and grass-like plants, and true to its family roots, it’s built for survival.

Originally from tropical and subtropical regions of the Old World, this grass has proven quite the traveler. It reproduces on its own in the wild without any help from gardeners, which speaks to its hardy nature.

Where Does It Grow?

Currently, you’ll find smut grass established in Guam and Palau, where it has adapted well to the local growing conditions. It’s particularly suited to USDA hardiness zones 9-11, thriving in those consistently warm, tropical climates.

The Good, The Bad, and The Grassy

Like many introduced plants, smut grass comes with both advantages and considerations:

  • Low maintenance: Once established, it requires minimal care
  • Drought tolerant: Can handle dry spells better than many ornamental grasses
  • Erosion control: Its root system can help stabilize soil
  • Adaptable: Tolerates poor soils and various light conditions

However, as a non-native species, it may not provide the same ecological benefits as indigenous grasses. While it’s not currently listed as invasive in the data available, its ability to self-seed and establish in the wild means it could potentially compete with native plant communities.

Growing Smut Grass Successfully

If you decide to grow smut grass, here’s what you need to know:

Growing Conditions: This grass is remarkably unfussy. It tolerates poor soils, drought conditions, and grows well in full sun to partial shade. It forms dense tufts of narrow, upright blades and produces delicate, airy seed heads that add texture to the landscape.

Planting and Care: Smut grass is low-maintenance once established. It can self-seed readily, so you may find new plants popping up around your garden. Regular watering during establishment helps, but mature plants are quite drought-tolerant.

Garden Design Ideas

In tropical and subtropical gardens, smut grass can serve several purposes:

  • Ornamental grass in naturalized areas
  • Ground cover for low-maintenance landscapes
  • Erosion control on slopes or coastal areas
  • Texture contrast in mixed plantings

Consider Native Alternatives

While smut grass can be a practical choice for certain situations, consider exploring native grass species first. Native plants typically provide better support for local wildlife, including birds and beneficial insects. They’re also naturally adapted to your specific climate and soil conditions, often requiring less water and maintenance once established.

Check with local native plant societies, botanical gardens, or extension offices to learn about indigenous grasses that might work well in your landscape design.

The Bottom Line

Smut grass is a survivor – hardy, adaptable, and low-maintenance. While it’s not a native species, it’s established itself in Pacific gardens for good reasons. If you choose to grow it, you’ll have a reliable grass that can handle tough conditions. Just remember to keep an eye on its spread and consider native alternatives that might provide even greater benefits to your local ecosystem.

Whether you’re dealing with challenging growing conditions or simply want a no-fuss grass for your tropical garden, understanding your options – both native and non-native – helps you make the best choice for your specific situation and gardening goals.

Smut Grass

Classification

Group

Monocot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Liliopsida - Monocotyledons

Subclass

Commelinidae

Order

Cyperales

Family

Poaceae Barnhart - Grass family

Genus

Sporobolus R. Br. - dropseed

Species

Sporobolus indicus (L.) R. Br. - smut grass

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