Zoysia grass is a popular warm-season turfgrass known for its density and low maintenance requirements once established. This species forms a thick, carpet-like lawn that suppresses weeds and tolerates a wide range of growing conditions. Since establishing Zoysia from seed is slow and unreliable, many homeowners use plugs—small, rooted sections of mature sod, typically 2 to 3 inches in diameter. These plugs are planted individually to spread and colonize the bare soil. Determining the precise number of plugs needed is the first step in a successful planting project.
Calculating the Total Area to be Covered
Calculating plug quantities requires accurately measuring the designated lawn area in square feet. For simple rectangular spaces, multiply the length by the width. Irregularly shaped yards should be divided into smaller geometric shapes, such as squares, rectangles, and triangles. Measure the area of each shape individually and then sum the measurements to find the total square footage. This precise measurement serves as the baseline for determining plug spacing and the final required quantity.
How Spacing Affects the Number of Plugs Needed
The distance between individual plugs significantly impacts both the initial cost and the time required for the turf to fully establish. Tighter spacing, such as 6-inch centers, results in faster coverage, often achieving a dense lawn within a single growing season. This option requires a much higher quantity of plugs, leading to greater upfront material costs.
Conversely, choosing a wider spacing, typically 18-inch centers, drastically reduces the total number of plugs and the immediate expense. This wider placement means the Zoysia grass will take longer to spread through its rhizomes and stolons, potentially requiring two to three full growing seasons. A common middle-ground choice is 12-inch spacing, which usually establishes a full lawn within one to two seasons, balancing cost and speed.
The Simple Formula for Estimating Plugs
Once the total square footage of the area and the desired spacing are determined, the number of plugs required can be calculated using a straightforward mathematical formula. The equation is: Total Square Footage divided by the Spacing Factor equals the Total Plugs Needed. The Spacing Factor represents the square footage of area that a single plug is expected to cover at a given center-to-center distance.
The common Spacing Factors are:
- 6-inch spacing: 0.25 square feet per plug (four plugs per square foot).
- 12-inch spacing: 1.0 square foot per plug.
- 18-inch spacing: 2.25 square feet per plug.
To calculate for a 500 square foot area using the 12-inch spacing, the calculation would be 500 divided by 1.0, which equals 500 plugs. If the same 500 square foot area were to be planted with 6-inch spacing, the calculation would be 500 divided by 0.25, requiring 2,000 plugs for the project. Zoysia plugs are typically sold in packaged quantities, often in flats containing 18, 50, or 72 units. It is necessary to round the calculated total number of plugs up to the nearest packaged quantity to ensure enough material is available.
Installation Best Practices
Soil Preparation
Successful establishment begins with proper preparation of the soil bed before planting. All existing weeds and competing vegetation must be removed to reduce resource competition with the young grass. Tilling the top few inches of soil improves aeration and drainage, and incorporating a soil amendment, such as compost, enhances nutrient retention.
Planting and Initial Care
Dig a hole for each plug just deep enough so the top of the plug’s soil is level with the surrounding ground. Planting the plug too high causes it to dry out quickly, while planting it too deep can smother the grass crown. After placement, firmly press the surrounding soil down to eliminate air pockets and ensure good root-to-soil contact. Immediately after planting, a thorough watering is necessary to settle the soil and hydrate the roots. For the first two weeks, keep the plugs consistently moist, and maintain initial growth by mowing at a slightly higher height (2 to 3 inches) than a mature Zoysia lawn.