Question
QUESTION: Which soil should be added to the lawn to make it denser?  The soil that was delivered was river soil according to the man.  Is this good soil for the Brownsville,Texas area or will it just not work for the water to drain properly as the dirt underneath the grass is clay.  We added topsoil some years ago and the dirt isn't draining. The water sits on the top of the grass and the roots never look wet unless we get a lot of rain.  Please respond asap as the soil is ready to be spread on the grass.

ANSWER: Hi Esther,

It sounds as if you are dealing with a layering problem which would only be compounded if you added more on top. To avoid this, you would need to thoroughly core aerate in order to create vertical channels in which the soil can fill.  That way, the water will drain down into these channels and then gradually seep into the underlying clay. When it is sitting on top, this typically won't happen.

Here's a link to an article I wrote a while back.  The soil textures are reversed from your situation but the concept remains the same.

http://www.thelawncoach.com/Columns/Entries/2008/8/19_Pond_Slop_as_Lawn_Topsoil.

Good luck.  Let me know if I can be of further assistance.

Sincerely,
C.J. Brown
www.thelawncoach.com

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QUESTION: That was the best informative column I've ever read and it is put in such layman's terms that I got what you mean.  I'll try the aerate the lawn.  But can you please tell me if floratam is the best warm season grass there is and where can I get it in the valley.  Please keep in mind that I live in Brownsville,Texas.

Answer
Thanks for the kind complement on the column. I always have fun writing those.

Floratam is a variety of St, Augustine grass that is very good. Whether or not it is "the best" is a matter of opinion that really depends upon what you are looking for.  Some folks will say yes, some will give you other options.  That said, it's pretty good stuff and I wouldn't advise you differently.

I'm not quite sure where you'd be able to find it locally, but I'm sure many local landscapers and/or garden centers would be able to either supply it or steer you in the right direction.

Good luck!

Sincerely,
C.J. Brown
www.TheLawnCoach.com