Green Waste Processing and Composting

When our crews pick up grass clippings, tree trimmings, and branches from city departments like Bureau of Street Services, Los Angeles Zoo, and Department of Recreation and Parks, that green waste doesn't just disappear. It is delivered to a processing facility where it is converted into reusable mulch or compost.

Our facilities use an aerobic composting method, meaning we rely on oxygen and heat to break down the organic materials naturally. The process involves:

• Cleaning out any trash or contaminants by hand.
• Grinding the materials to reduce their size.
• Building large compost piles.
• Allowing the materials to compost for 30 to 60 days.
• Screening the final product to ensure a smooth, beautiful texture.

We use a variety of materials to create our compost, including yard trimmings, wood chips, horse manure, and even herbivore animal manure mixed with discarded bedding from the LA Zoo!
 

We want you to feel completely confident when putting our compost in your garden. That is why LASAN participates in the US Composting Council's Seal of Testing Assurance (STA) program.

Before the year 2000, there were no nationally accepted laboratory tests for compost. The STA program changed that by creating strict, uniform testing standards. Just like a nutrition label on your food, the STA certification ensures that our compost is regularly sampled and tested by certified laboratories.
 

Our STA-registered compost products—including Griffith Park compost and our horse manure compost—undergo quarterly lab analyses. We test for beneficial properties like pH and nitrogen levels, while simultaneously screening for bacterial and metal contaminants to protect public health and the environment.

Because of the high temperatures reached during our commercial composting process, pathogens are naturally destroyed. This means our TOPGRO compost and mulch products are perfectly safe to use in your home gardens, including fruit and vegetable beds.