Is it possible (or should I ask practical) to amend existing clay soil with expanded shale without damaging the existing lawn? My thought is to use an aerator on the lawn first, then spread the expanded shale. However, I believe this may be a problem since it sounds like the shale chunks are rather large (0.5-1"). What do you guys and gals think?

Also, is there a better amendment I should use for the purpose of aerating the heavy clay soil?

BTW, lawn is Bermuda.

Thanks,
Kevin

I would use a quality compost & lava sand (also any other amendment you can afford). You can probably get both for much cheaper than the expanded shale.

I added alot of compost last year, but I think it was probably not "quality" since it appears to have had lots of weed seeds in it. My lawn was virtually weed free last spring, but this year they are everywhere & thicker where the compost was applied heaviest.

I know lava sand is pretty cheap ($5-6 for 40#). Guess I should check prices on expanded shale around here. I was already going to do dry molasses again & possibly corn meal too.

Also, still waiting for my soil test results to come back from Calloway's Nursery free soil test promo.

Thanks,
Kevin

If you applied compost and could distinguish where it was applied "heaviest," then you probably used too much. The "proper" application rate is 1 cubic yard per 1,000 square feet. This should go on like dust - barely visible. I guess my point is that if your compost was visible, then any weed seed (whether already in the compost or blown in later), would have a place to see the sun and, therefore, germinate and take hold with a root.

The absolute best defense against weeds is a relatively dry soil surface and tall grass (above the level of any rooting medium). You can keep your soil relatively dry by only watering once a week. I realize Mother Nature has her own ideas about when to water, but you do have some control over your own contribution to the moisture level. The second way to prevent and control weeds is to keep your grass tall. Weed seeds that sprout in the dense shade of tall grass will not get enough sunlight to photosynthesize and establish a root.

For your current weed problem I would pick all the broadleafed weeds either by hand or with a Weed Hound tool, and let the grassy weeds get choked out with tall turf grass. There are a few clumping grassy weeds that you can pull with a Weed Hound, so go for those with the tool, too.

By heavier areas, I know this for two reasons. One is that I intentionally applied a heavier layer in two large areas that seemed to be lacking something since the grass was not growing well there. Second is that the compost was really "uniform" in particle size as there were many wood chip-like pieces that are easily spotted if you look closely. That's partly why I believe the compost was not quality since it appeared to not be "finished" yet.

I think this year I will spend a bit more & buy the "topdressing" compost rather than the regular compost since it is screened finer.

Kevin

I would suggest not buying any more compost in your lifetime and concentrate on using organic fertilizer instead. The compost provides nothing but microbes. More microbes without food means less nutrition for your plants. If you start adding food now, the microbes will become more healthy and will reproduce for you without adding compost.

For bermuda you can go with the heavy hitters, those being soy bean meal and/or corn gluten meal. They have more protein in them than ordinary corn meal or even alfalfa.