Zoysia seed germinates very slowly, so most Zoysia grass is only available in stores as sod. This is wise because it can take up to 12 months for sprigs or plugs to merge and cover a lawn area.
Also, unless you’re extremely patient, you should cover the entire planting site with Zoysia sod. Remember, too, that Zoysia grass is especially slow to grow if planted in the shade.