St. Augustine grass is a popular choice for warm, humid climates across the southern United States, known for its dense, coarse-bladed, blue-green turf. Unlike many lawn varieties grown from seed, St. Augustine grass (Stenotaphrum secundatum) is established through vegetative propagation, primarily using sod or runners. Runners, technically called stolons, are above-ground horizontal stems that produce new roots and shoots at their joints, or nodes. Using runners is an economical approach to establishing or repairing a lawn, offering a significant cost advantage over purchasing sod. The process relies on careful preparation and precise planting to ensure the stolons successfully root and establish a healthy, vibrant lawn.
Optimal Timing and Site Preparation
St. Augustine grass is a warm-season turf requiring consistently warm temperatures to actively grow and spread. The optimal window for planting runners is late spring through early summer, typically April to May, when the soil temperature is warm and the grass is emerging from dormancy. Planting runners during late fall or winter is ineffective because the stolons need a minimum of 90 days of warm growing conditions to successfully root before the first expected frost.
Proper site preparation must be completed before planting. First, clear the area of existing weeds, debris, and old turf, ensuring any non-selective herbicide used has no residual effect. Next, cultivate or till the soil to a depth of four to six inches to loosen compaction and ensure good drainage, as St. Augustine grass does not tolerate waterlogged conditions.
The soil should then be raked smooth to create a level surface, removing any rocks or large clods that could interfere with runner-to-soil contact. A soil test helps determine if the pH is within the ideal range of 5.0 and 7.5, allowing for necessary amendments. Optionally, mix a small amount of starter fertilizer or organic compost into the top layer during final raking to provide initial nutrients, particularly phosphorus, which aids root development.
The Runner Planting Technique
The process begins by selecting or harvesting healthy, vigorous runner segments, or stolons. Each segment, often called a sprig, should contain at least two nodes—the joint-like points where roots and new shoots emerge. These nodes must make firm contact with the soil to initiate rooting.
Lay the runners out on the prepared soil surface at measured intervals to ensure even coverage. A common technique is planting runners in rows spaced 8 to 12 inches apart, with individual sprigs placed every 4 to 6 inches within the row. Closer spacing results in a faster fill-in rate but requires more material, while wider spacing is more economical but extends the establishment time.
The runners must not be buried completely; instead, press them firmly into the soil so the nodes contact the moist dirt. Partially bury the runner, typically one to two inches deep, while leaving a portion of the stem and leaf blades exposed to light. This partial burial protects the runner while allowing the exposed parts to photosynthesize.
Gently firm or tamp down the soil around the runners to eliminate air pockets and maximize the soil-to-runner connection. Rooting requires consistent moisture and close contact with soil particles. Specialized U-pins or wire staples can be used to secure runners in place, especially on slopes, ensuring the nodes remain anchored until roots take hold.
Immediate Establishment Care
Care immediately following planting is essential for successful rooting during the establishment phase, which typically lasts four to six weeks. The primary focus in the initial days is maintaining balanced moisture in the upper soil layer where the nodes are generating new roots.
A light and frequent watering schedule is recommended for the first 10 to 14 days to keep the top inch or two of soil moist without causing saturation or runoff. Water once or twice a day, especially during warm morning hours, to prevent the runners from drying out. After the first two weeks, gradually reduce the watering frequency to encourage developing roots to grow deeper into the soil.
A light application of starter fertilizer, formulated to be high in phosphorus, stimulates robust root growth. If starter fertilizer was not incorporated during preparation, apply it approximately two weeks after planting, once runners show initial stabilization. This provides a nutrient boost for emerging roots without promoting excessive top-growth that could stress the new grass.
Foot traffic must be restricted until the runners have fully rooted and show active, new growth. Delay the first mowing until the grass blades reach about six inches, usually three to four weeks after planting. Set the mower blades at their highest possible setting, generally three to four inches, to avoid stressing the fragile new turf.
Successful rooting is confirmed by gently tugging on a runner; resistance indicates that roots have anchored the node to the soil. Monitor runners for discoloration, such as browning or drying, which signals insufficient moisture and requires an immediate adjustment to the watering schedule.