Purple blades on St . Augustine

lornabr – posted 27 February 2007 03:25

I recently noticed the blades of my St Augustine are turning a dark purple along the sides and tips. My lawn was treated by a lawn care company on Jan 29. This also took place within a few weeks last year around the same time shortly after lawn treatment. Last year the grass became progressively worse after this and took several months to start looking normal.The lawn care professionals came back yesterday and told me the lawn had frost damage that had caused the purple blades.Could someone tell me what will cause the purple blades, and if there is something I need to do now to help it before its to late? Thank You in advance.

amftx – posted 07 March 2007 08:48

I had the same issue, and all of the research I did pointed to too overwatering or watering too frequently for short periods (10 nmins 3x a week), instead of less frequently for a longer period (30 mins 1x a week).

If you look on the under side of the blades you will see that the bottom and/or base of the blade is still green. What happens is that water sits on the upper parts of the blades and it’s either a fungus or just water saturation that causes the purple color.

Water less frequently and a bit longer so that the water will go deeper into the soil, and you don’t have so much water sitting on the surface of the grass all of the time. St. Augustine should heal or grow out and the purple parts will be mowed off. If your runners are also purple, it might take a bit longer to heal.

This happened to me over the winter and when I stopped watering and then adjusted my watering schedule, it’s clearing up.