Guv Bob wrote:
"David E. Ross" wrote in message
...
On 6/27/2014 2:47 PM, Guv Bob wrote:
"Brooklyn1" wrote in message
...
Guv Bob wrote:

How's a good way to break up hard soil? Since it's all level, my
first thought is to soak it good for a couple of days. I wonder
if renting an aerator might also be good.

An aerator won't do much on hard-pack adobe like soil except break
the aerator... aerators only poke holes, some extract plugs, but
they are meant for reasonably soft soil that may be slightly
compacted from foot traffic.

Most of the soil is fairly easy to dig down 2-3 inches, but about
1/4 of the back yard is bare & hard as a rock. When I was taking
soil samples, I had to use a pick to get down that far. But the
whole yard is dry and hard deeper than 3-4 inches.

That kind of soil won't let you grow much, let alone a lawn. First
where are you located? Geographical location plays a large part in
soil conditions. In many parts of the US southwest the soil is
indeed like cured concrete, breaking it up will will only result
in it going back to hard after the first couple of heavy rains...
then the best tack to take is to haul in lots of good top soil and
do your planting in that... it would cost too much to amend the
type of soil you describe and it won't be long any organic
amendment will decompose like it was never there.


Thanks. So Cal. According to a county site report for a shopping
center in the area, it has a base of older alluvial interbedded
silty
clay and clay, overlain by interlayered sandy gravel and silty clay.


Thus, you likely have enough clay that gypsum would be appropriate.

The charts say all the grasses I have required 6-7pH. Soil is
6.5-7.0 more or less. I thought gypsum would make it alkaline.

No it will not alter the pH. As others have said you have a choice.

Quick: bring in topsoil, re-seed or turf in one go, more expensive and more
hard work in a short period, still not a bad solution if you can afford it.

Slow: fix what you have. Gypsum or other clay breaker treatments, adding
organic matter, re-seed progressively. This will work in the long run and
be cheaper but it will take perseverance and a sustained effort.

Which is better depends on you and your situation.

David