Dallisgrass from Seed: Erosion Control Timing & Establishment

Why Dallisgrass Works for Erosion Control

Dallisgrass (Paspalum dilatatum) has earned recognition as a powerful erosion control solution because of its unique growth characteristics. The grass is known for being fast growing and very adaptable, with abundant rhizomes and a deep, fibrous root system that confer tremendous drought-resistance and erosion control properties. These deep roots anchor soil in place, preventing washout during heavy rainfall—a critical factor since most erosion occurs when water moves soil before grassroots establish.

One of the best ways to control erosion is with healthy, dense grasses. Unlike shallow-rooted species, dallisgrass creates an anchor system that holds soil firmly, making it particularly effective on slopes and hills where runoff poses the greatest risk.

Timing Your Dallisgrass Seed Planting

Successful dallisgrass establishment depends on planting during the right season. Since dallisgrass is a warm-season grass, plant seed when soil temperatures are consistently warm and the growing season is active. This allows the grass to establish roots before cooler months arrive. Avoid planting during dormant seasons or before heavy rainfall events that could wash away unestablished seeds.

Consider your local climate: dallisgrass tolerates lower temperatures than bermudagrass before going dormant, giving you a slightly extended window for establishment compared to other warm-season options.

Site Preparation and Seeding

The first step is always to prepare your soil just as you would for any other planting. You want to create optimal conditions for your seed to grow. After your site is prepared, spread the seed and apply the necessary fertilizer. This helps to promote vigorous and deep growth of the erosion control seed roots, preventing your grass seed from washing away when there is rainfall by providing them with an anchor in the soil.

For vegetative barriers and concentrated flow areas, seeding rates should be between 10 and 20 pounds of PLS (pure live seed) per acre. Prior cultivation should provide a clean weed-free seedbed. A brillion seeder can be used to firm the soil, drop the seed, and press it into place for better contact.

Protecting Seeds with Starter Mats

Seed starter mats stabilize and protect your seed along with hillside erosion control products. They can be cut to size, so they fit precisely to your hill or slope. The mat can be secured using landscape staples, which are available at most garden and hardware stores—place the staples every 5 to 7 inches along the mat.

These mats offer multiple benefits: they help prevent the growth of unwanted weeds, which removes competition for your erosion control seed, allowing it to grow easily and freely. The mat is designed to biodegrade naturally, so there's no need to remove it manually as your grass starts to grow.

Watering for Successful Germination

Water your matted area regularly, at least once a day. This keeps the soil moist to enable the seeds to germinate. Consistent moisture is essential during the establishment phase—this is when seeds are most vulnerable to erosion and environmental stress.

Once germination occurs and roots begin to establish, you can gradually reduce watering frequency, though you should maintain adequate moisture until the grass is fully established and can access deeper soil water.

Maintaining Your Established Dallisgrass

The erosion control grass seed will allow for the continued growth of your site, and you must, therefore, follow the best mowing practices to maintain a low grass height. In mowed sites, keep vegetation at a height of at least 15 inches throughout the year for optimal erosion control, though you may mow lower for aesthetic purposes if needed.

Dallisgrass responds well to nitrogen fertilizer and is highly competitive against other plants in fertilized sites. If mowing is not possible, you can skip this step and instead focus on having an erosion-free slope that is left in its natural growing state.

Key Terms & Concepts

• Fibrous root system: A network of fine roots that spread horizontally and vertically, providing excellent soil anchoring
• Rhizomes: Underground stems that allow the grass to spread and regenerate, increasing density over time
• PLS (Pure Live Seed): A measure of seed quality accounting for purity and germination rate
• Vegetative barrier: A strip of dense vegetation planted to slow water flow and trap sediment
• Concentrated flow: Water movement along specific paths on slopes, creating erosion risk

Expert Perspective

Dallisgrass is used for erosion control and for mine habitat restoration because of its ability to establish quickly and create dense ground cover that stabilizes soil. Its deep root system makes it particularly valuable in areas where traditional erosion control methods may be insufficient.

Key Statistics

Dallisgrass grows up to ten times faster than regular turf grass, causing visible coverage between mowing cycles. This rapid establishment is one reason it's particularly effective for erosion control on slopes where quick soil stabilization is critical.

Sources

• Vegetative Barriers For Erosion Control – USDA NRCS
• Dallisgrass Offers Benefits – University of Hawaii CTAHR
• Paspalum dilatatum (dallisgrass) – CABI Compendium