Zoysia Fertilization and Watering
A seven week schedule is commonly recommended for Zoysia starting in the Spring after the grass is 75 to 100% green continuing on to mid September. My preference is 3 times, Once in Spring, again in summer and optionally a fall fertilizer using a “winterizer”. Commercial grade lawn fertilizers (16-4-8 being an example) are fine. Generally you should look to apply 2-4 pounds of Nitrogen per 1000Sq ft per year (See my section on Fertilization for an explanation of how this translates into the fertilizer you are using).
Since Zoysia prefers an Alkaline Soil the use of lime is also recommended. Most experts recommend that you have your soil tested to determine how much lime to add. Most of us are reluctant to go to that extreme; in that case the recommendation is to use 40# of granular lime per 1000Sq Ft Once per year. Lime can be applied at any time but my preference is to apply it after aerating and fertilizing.
Once well established Zoysia is highly tolerant of droughts but does require watering. Zoysia should be watered when it shows signs of requiring it. A sign that Zoysia is in need of watering is when the leaves start to curl inwards. As a rule of thumb, Zoysia will require about 1 inch of water per week. Morning and early afternoon watering is preferable as it gives the turn a chance to dry off before evening, lessening the chance of disease.
For Turf lawns the recommendation is that receive a minimum of 1-2 inches of water a week, more watering will produce a healthier, better looking lawn.