Grass Clippings: A Free Mulch

Grass clippings around tomatoes and peppers

The suburbs, green as they are, produce a huge amount of plant waste in the form of tree trimmings, uprooted shrubs, autumn leaves, and so on. But the most plentiful and sometimes problematic green waste -- grass clippings -- can actually be put to use in the garden as a weed-suppressing, moisture-retaining mulch.

It's simple. If you mow the lawn and gather the clippings in the bag, just spread those clippings in a two-inch layer around established plants like tomatoes, onions, peppers, and so on. The clippings will eventually dry out to a straw color with a crusty surface. This will provide two advantages: First, the crusty top will keep weeds down; those that are able to poke through will be an easy-to-see green against the yellow grass, and they will be shallow-rooted and easy to pull. Second, in the height of summer, when the sun is really beating down, the yellow grass will shade the dirt and help retain moisture. Eventually, the grass clippings will rot down into the soil, providing valuable organic material to the dirt.

Grass clippings around onion plants.

Now before you start spreading clippings on your garden, there are some potential problems to consider:

• If you douse your grass with lawn fertilizers, you might not want to put the clippings on your garden. Many fertilizers contain herbicides and chemicals like 2,4-D, which could not only harm your veggies but also harm you. 
• If you have a dog that poops in the grass, it might not be a good idea to spread this on plants you're going to eat. Same goes for grass that might have lead-paint flecks in it. 
• If dandelions and other weedy plants are producing seeds in your grass, you might not want to spread that on your garden. You might be making weeding work for yourself in the future. 

I often "steal" my neighbors' bagged grass, but the concerns above still apply -- I don't use it if I think that it might be contaminated in any way. However, with bagged grass, you should be aware of another concern: Bagged grass sometimes starts to ferment in the bag -- it gets hot and smells like vinegar. That's good in the sense that weed seeds are often killed under those conditions; but you should try to air out and/or rinse the clippings before applying them to your garden. Veggies tend not to like vinegar on their roots.

Otherwise, I've found this to be a great way to cut down on weeding and to provide a more pleasant look to my garden. For more information, consult some of the sources linked here.