My lawn in my front yard is looking really not that great -- many
areas are kind of thin, not dense. I am wondering what I can do to
make it become thick and healthy.

Contrary to the lawn in my front yard, the lawn in my backyard is
looking great. This is surprising considering the fact that the front
yard is facing south and is sunny-to-part-shade, and the backyard is
facing north and is part-shade, and the grass is Kentucky Bluegrass
that is supposed to prefer more sun.

I can see the only possible reason why the backyard lawn is doing
great has to do with the fact that it has 3" to 4" top soil while the
front yard only has 1" top soil (the sub soil in both cases are
sandy).

I tried to improve the front yard in the fall of last year by adding
1/2" top soil onto the front yard after I reseeded the lawn.
Everything looked promising in spring; grasses were emerging from
where that was thin before. But by early summer, the situation became
worsen. The lawn in my front yard started thinning again. What should
I do now?

My questions a

- I believe this has something to do with too little top soil and the
sandy soil cannot hold water that well, and I probably need to water
more often than what I am doing now. I have already made sure the lawn
got at least one inch of water a week. Does the sandy soil require
more frequent watering, such as twice a week?

- I have been using a soil-sampler to check the moisture of the soil
periodically to see when I should start watering, and I think that the
soil is still slightly moist at 6" deep most of the time. May be I
just don't "feel" the soil correctly. May be the soil was very dry,
but I thought they were still moist. What's the correct "feel" that I
should go for?

- I have a feeling that I should add more top soil or compost in this
fall. While I am waiting for the fall, I am wondering what else I
should do right now. Does putting in organic fertilizer into the lawn
has the effect of adding more top soil (let say every month)? Should I
add more water? Should I add more water _and_ add more organic
fertilizer?

Please help. Thanks.

Jay Chan




You're correct that depending on soil type, more frequent watering may
be needed. One inch about once a week works with good, deep soil and
reasonable temps. With poor soil and/or high temp, more frequent
watering will be necessary. In any case, it's best to water deeply
only as often as it's needed. You can tell if it needs water by
looking at it. The grass tends to get a bluish color and will not
spring back when stepped on if it needs water. And all this is for
mature grass. If you seeded this spring, that grass needs to be
watered more frequently until it becomes established. I see people
seeding and then, after about 6 weeks, just letting it go, treating it
like the rest of the lawn, which results in most of it dieing.

If you really have only 1 inch of topsoil, then starting over and
having topsoil brought in is the only real solution. But, are you
sure of what you have? Is it just the first inch is different, the
rest being sandy loam type material or is it really pure sand? Also,
have you had the soil tested, particularly for PH? Have you
fertilized, particularly in early fall and then about 6 weeks later?
If it doesn't green up quickly after applying nitrogen, that's a sign
of improper PH.