Question
Looking to change my centipede lawn to st. augustine.  I have a relativeley small lawn so the amount of sod is not an issue.  however, I dont know how to get rid of the current grass.  should I till up the centipede and lay down the st augustine or plug the centipede throughout.  I dont feel like waiting years for the st. augusting to take over.

Answer
The most effective treatment is to spray the existing lawn with an EPA approved herbicide and wait till it dies. Typically, a couple of weeks. Then you can scrape the old sod off the top soil or till it in before laying the new sod. Either way, you must expose the top soil for the new sod, do not lay new sod on old grass. If it is not a big area some people have laid 6mil black plastic over their yards and staked the edges down creating an "oven" to effectively kill the grass by heat with no chemicals...but this is only marginally successful in my experience and yard must get plenty of sun for this to work.

Best of Luck

Sean Murphy
Sean J Murphy, LA,ISA, LEED AP
Please check out my blogs and articles on landscape topics like this on my websites.
http://www.seanjmurphy.com
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