Pros: Adds micronutrients and increases biological activity in the soil. Increases soil porosity, which increases water utilization.
Cons: If not done properly, often brings in insects and weeds. Often applied too thick, which suffocates the lawn, depriving it of sunlight. Poor quality compost can bring in insect and disease problems.
It seems everyone is jumping on the top dressing bandwagon. In Cedar Park and Round Rock, there are a couple of companies selling the application of a Dillo Dirt top dressing. They are selling 1/4″ to 1/2″ of product, applied over the lawn. What they are delivering is 1/16″ to 1/8″ of a 30% chocolate loam mix. Organic Compost mixed with a variety of supplements is preferred for Austin while Dillo Dirt isn’t. People are confused between top dressing, composting and lawn leveling. You level with sand, not compost. Compost that you make on your property is a great thing for your gardens and beds. Unfortunately, most of the commercially available compost blends aren’t turned properly, nor are they allowed to get hot enough. Furthermore, they are nothing more than yard waste, taken to the landfill.
Top dressing with top soil or sandy loam adds no nutrients or microbial activity to the soil and is a poor choice for leveling. If you need to level your lawn, use sand. Sand increases the porosity of the soil. Austin soil has a very high clay content, and sand helps keep your soil loose. Never spread more than 1/8 of an inch at a time. Use common play-sand found at Home Depot. If you want to increase the micronutrient levels in your soil and increase microbial activity, use Milorganite, Houactinite and a compost tea. All can be applied by way of a hose end sprayer. These products won’t bring in any insect, disease or weed issues.
If you want to increase the efficiency of water applied to you lawn and landscape, there are many products available to do this, ranging from Surfactants, Humic Acid and Hydrogels. Aqualizer is the only product that is a combination of all three.