I top dressed back in 2003 but probably never will again. Compost is far too expensive for my means. We pay about $40 per yard plus up to $50 for delivery.

1/2 inch is a bit much. The problem is smothering the grass to death under the compost. 1/4 inch is plenty. That works out to 1 cubic yard per 1,000 square feet (more accurately 1/3 inch so you have to be careful). I used a push broom to lift up the grass blades and allow the compost to fall down in.

Have you read the Organic Lawn Care FAQ? It is on many websites. Here at GW it can be found in the FAQs on the Organic Gardening forum.

How often you need to "topdress" depends on your soil. How much organic matter is in that soil now? What level of humus to you want to maintain? Some soils may only need a 1/2 inch application each year while others may need much more, at least initially.

I started going organic by mulch mowing grass and leaves and adding organic matter to the lawn instead of chemical fertilizers, mowing high and watering infrequently but deeply.

I mulch/add leaves and fertlizer with cracked corn, rabbit food, milorganite, or soybean meal in the fall. If I have compost that is not used in the garden or beds, I spread it on the lawn.

Why do you want to topdress with compost?

David and I agree on most tips, but differ some here.

The biggest boost I ever did for any yard I owned came after topdressing at 1 cubic yard per thousand square feet.

But, keep in mind, it all depends on what you have now. If you have a soil with organic matter and lots of bio-diversity already (meaning it hasn't been nuked too much by over application of chemicals and chemical fertilizers) you may not see much benefit from topdressing with a good compost.

If your yard is on the other end, I think at least one application of a good compost is the best way to start an organic approach.

But, the cost and hard work involved is fairly high.

After one app, I would imagine compost tea and organic fertilzers could make the need for additional apps few and far between as something that is needed, rather than desired for best effect.

A tip from a frugal gardener: in some cities you can get decent compost free from the dump. Where I live in Atlanta, I can get compost from the county dump for free. It's a little rough,but you can always screen it if you need it very fine. Then I sometimes add a small amount of homemade compost to boost the nutrient value before using it. I've never used this on lawns, but I garden organically and have made lots of planting beds out of it and it works great. As a side note, if you go this route I would check and make sure that the compost where you are is not made out of sewage sludge, which I've heard can have chemical contaminants that aren't good.

Good points.

In San Antonio the municipal compost is mostly dirt. That's not necessarily a problem but it will raise your surface profile and create high spots. -just something to look for in your local compost.

We also have a brand of municipal compost that is made from sewage. Although the incoming sewage is tested continually for contaminants, and they pass the Federal levels, it does not mean the contaminants are at 0.00%.