Personal tools


Email Signup

Receive updates on special events, classes, hot topics and more.

Privacy Policy

Supported by United Way of King County.

United Way of King County Logo
You are here: Home ›› Learn ›› Master Composter/Soil Builder Program

Master Composter/Soil Builder Program

Find out how Seattle residents are helping other Seattle residents manage organic wastes for a healthier city.

Teaching Sustainable Practices, Stewarding the Earth

MCSB 2016

The Master Composter/Soil Builder (MC/SB) volunteer program is a key partner in Seattleā€™s waste reduction and recycling efforts. We help city residents to build worm bins, recycle food and yard waste at their homes, build healthy urban soils and support thriving landscapes throughout the city.

Become a Master Composter/Soil Builder

If you love composting and you're interested in public education and outreach, apply to become a Mater Composter! Receive in-depth compost education with a team of diverse Seattle residents, then share your valuable knowledge and experience with the wider community. Find out more...

Apply Button

We Will Visit You Anywhere in Seattle!

Master Composter/Soil Builders volunteers will come to your location to share with your group what they know about composting food and yard waste, how to set up a worm bin or other compost system, and how you can build healthy soil.  Find out more...

Live Outside of Seattle?

Find out about the new soil and water stewardship training in Kirkland and Renton.

Composting Resources

  • The Master Composters have put together an audio series. Enjoy listening to this crash course about how to think like a Master Composter and take advantage of some of the education which goes well beyond composting. Listen now.
  • Learn about composting by reading our composting info sheets. 
  • Tilth Alliance offers composting classes. Register for upcoming classes.

About Us

The Master Composter/Soil Builder program is a part of the Natural Soil Building program, managed by Tilth Alliance (formerly Seattle Tilth) and sponsored by Seattle Public Utilities. We began in 1986, training volunteers to teach others about composting. We have shared our model with other organizations in the U.S. and they have created similar programs. Today there are more than 500 Master Composter training programs in North American and abroad.

Contact Us

Justin Maltry is the Master Composter/Soil Builder program coordinator. Contact him at
(206) 633-0097 or


Enjoy this lively, professional video about composting! It's from "Growing A Greener World" with Joe Lamp'l, Nathan Lyon and Patti Moreno. Graham Golbuff, Resource Conservation Program Educator, leads a compost workshop and gives a little tour of our first community learning garden in Wallingford.


Document Actions
powered by Plone | site by Groundwire Consulting and served with clean energy