Ask Mr. Smarty Plants

We're a little confused by your question. Ordinarily, the only liquid that would matter when you are growing plants would be water, and we don't ever remember anyone referring to water as "thick" or "thin". For instance, water can be measured by how deep it is, and if you put two inches of water on a plant all at once, and it's not draining, it could drown the plant. Or, could you mean the water was thick with other things, like dirt, or mud? If you pour muddy water on a plant, the dirt in the water will join the dirt around the plant, and the water will go to the roots, like it's supposed to.

Or were you, perhaps, thinking of reusing water used to wash dishes or clothes, and therefore a little thicker or more dense with soapsuds or food particles. This is called "Gray Water" and in this article on Residential Water Conservation you can read about some of the kinds of leftover water that can be used on plants. The article suggests that such water be used only on ornamental plants, trees or grasses and not on plants that will be eaten, like carrots or lettuce. In drought-stricken area, this may be a way to keep some valuable plants alive. However, many towns and cities have strict rules about what kind of water can be used, and whether it has to be filtered before it is used.

If we still haven't found a way to answer your question, send in another, maybe rewording it a little so we can understand better what you are trying to find out.