When doing research to decide why you should go with Zoysia plugs over Zoysia seed, here is an in-depth look at factors you must consider:
Time - Zoysia grass takes 21 days on average to germinate and 90 days for the grass to start becoming mature. In that time, weed pressure can out compete and kill off your seedlings. Plugs on the other hand, are already established, therefore hardy against weeds.
Watering - When planting seed, the watering requirements can be upwards of 4 times a day, for varying lengths of time over 2 months. Due to the very involved and intricate watering schedule sometimes the seeds can dry out and die. This results in wasted time and money. With Zoysia plugs you only need to water for an hour per day (in the mornings) for the first two weeks after planting or until the grass is established.
Temperature- The optimal soil temperature for Zoysia germination is a steady 70 degrees Fahrenheit. Temps that are too hot, too cold or fluctuating can result in less than optimal germination for your grass. Plugs on the other hand, are already established so they are more tolerant to varying temperatures.
Conclusion: Plugs are a much easier way to achieve an established Zoysia lawn. The hardest part of the growing cycle is already over by the time you receive your plugs.