Frost Damage on Warm-season Turf

If you grow a warm-season grass, the first frosts of the season usually spark a few phone calls or e-mails to the extension offices regarding something terrible happening to the lawn in terms of its color and appearance.  When a killing frost arrives, the leaf blades of warm-season grasses will be damaged by the freezing temperatures and the blade will quickly turn brown as the turf slowly enters its winter dormancy period.  Over the years I have heard this phenomenon called ‘psychedelic turf’, ‘psychedelic grass’, ‘leopard turf’, ‘zebra turf’ and so forth.  

There was even a rumor making its way around the south several years ago that it was due to a chemical weapons experiment gone astray.  Take the opportunity to see what I am talking about on the Turf and Garden Tips webpage and you will quickly associate why such crazy names for the turf have developed over the years given the random green and brown stripes seen in the lawn.  When the first frosts of the season occur, the temperatures are typically not so drastically cold that complete blighting of the turf canopy occurs;  there are variances in frost formation (and therefore, leaf damage) depending on turf canopy height and density across the lawn that results in slightly different temperature and moisture levels in pockets across the lawn.  Bermudagrass and zoysiagrass are the warm-season lawn grasses that are most likely to display these patterns due to their extreme densities and fine leaf texture.  As bad as it looks, there is no concern for the turf and subsequent frost events will eventually result in a completely brown, uniformly dormant turf.   But for a few days, you can truly marvel at one of Mother Nature’s best displays of modern art!