Q: Why is zoysiagrass so late to green up each year? Our lawn looks like it isn’t coming in well.

 

A: Yes – in some years zoysiagrass won’t be completely green until June. It might be caused by several things:

• Scalping too early (soil temps need to be 60 degrees and steadily rising)

• Applying Nitrogen too early (soil temps need to be 65 degrees or higher)

• Thatch layer is too thick, preventing soil warm-up

• Large Patch disease. See Large Patch on Zoysiagrass

• Previous year misapplications of fertilizer or herbicides

• Irregular weather patterns (very cold in mid December, warm enough in January to start breaking dormancy followed by more cold, then a late frost in 3rd week of April)

• There are also genetic off-types of ‘Emerald’ Zoysia being sold. ‘BK-7’ zoysiagrass looks like ‘Emerald’ but does not green up like ‘Emerald’ zoysiagrass.

This paper by Dr. Clint Waltz explains it:

‘Emerald’ Zoysiagrass: Genetic Techniques Explain Common Observation