Learning All Things Compost at the Vaca Valley Garden Club

Sep 24, 2025

By Jill Hopkins, Vaca Valley Garden Club

We were excited to bring speaker (and composting expert extraordinaire!) Lori Caldwell to the Vaca Valley Garden Club for their September meeting. Here, club Vice President Jill Hopkins shares about Lori’s talk and the garden club.

Lori Caldwell presents all about compost

At the first regular meeting of the 2025-26 year for the Vaca Valley Garden Club, 54 members and guests were treated to the energy of Lori Caldwell, The “Compost Gal,” on Sept. 10. Lori’s presentation covered a series of compost contrasts for the Garden Club when she spoke of the appropriate Brown/Green Ratio; the difference between Damp and Mushy; the distinction between Aerating and Turning, and the distinct qualities of Hot vs. Cold piles.

Some important compost tips:

  1. Aerate that pile like you are “tossing a salad,” not stirring pancake batter!
  2. Chop your ingredients before adding them to your pile. Do not “dump and run.”
  3. Know your compost’s mood. Too much sun? Too much water? Bad bugs? Stinky? All fixable!
  4. Compost Happens! The time it takes depends on the ingredients, the care, and attention it gets, like most things in nature.

Sustainable Solano connected Lori Caldwell, consultant, landscaper, and educator, with the Vaca Valley Garden Club. In turn, Lori’s expertise in All Things Compost got people excited about a positive use of leaves, fruit peelings, straw, eggshells, tea leaves and branches. It was a good day for the Garden Club and a good day for Mother Earth!

Vaca Valley Garden Club

The Garden Club welcomes everyone with an interest in flowers, vegetables, trees, water, bees, bugs, birds, and the preservation of natural resources.

For additional information about the Vaca Valley Garden Club, attend one of its meetings at 10 am on the second Wednesday of the month (September-May) at Presbyterian Community Church, 425 Hemlock St., Vacaville. Before each meeting, an informal plant sale and boutique are held. Call President Glenda Riddle at (707) 330-8338 to learn more about the club.

EcoFarm Insight: Reflection, Observation & Irrigation

Feb 26, 2025

By Patrick Murphy, Program Manager

I had the opportunity to attend EcoFarm’s 45th Anniversary conference this year and had a wonderful time. My colleagues and I attended a variety of presentations and participated in a number of wonderful discussions with people from around California who work on similar projects related to urban agriculture, local food, and creating connections in their community.

There were a number of wonderful presentations that affirmed going back to basics like water retention, soil health, building up organic matter and biological activity, as well as taking your time to plan each project.

Again and again I heard from folks working in agriculture, education, farms and gardens that they had the most success when they took their time to reflect and observe before acting. Taking deliberate and well-paced steps to mulch, to build up organic matter in the soil, to increase water infiltration, and to develop rich and biologically active soil were the most impactful things they did. They stressed the importance of avoiding jumping into an idea that sounds good but is untested — the sheer force of nature is too powerful to work against.

Some key recommendations:

  • Take your time when you’re planning, and revisit a site multiple times before beginning work, with and without your plans.
  • Install a flow gauge and Schrader valves (similar to bicycle tire valves) in your irrigation system, and use a pressure gauge to check your system for leaks and issues.
  • Heat stress can make plants more prone to pest issues.

Here is a breakdown of some of the presentations:

Regenerative Landscaper Erik Ohlsen gave a talk about the importance of getting to know a site. He said that to truly understand a location, you should be visiting it in the rain, at night and early morning, and you should always check and recheck your plans with the reality of what is on the ground. Ohlsen also stressed the number of career opportunities which exist in landscape design.

Cameron McDonald from Santa Cruz Resource Conservation District spoke about the importance of monitoring water systems using flow gauges and pressure gauges. McDonald spoke about how farmers (and homeowners) can balance design, operations and maintenance, and irrigation scheduling to maximize yield, conserve resources, minimize nutrient loss, ensure uniform crops, and reduce fuel costs.

The mantra was “You can’t know what you don’t measure” — measuring flow rates is essential, and tools like flow meters for home gardeners, or telemetry systems, data loggers, and remote data collection for large-scale operations provide an enormous amount of information. SRCD has a number of common recommendations they offer to improve efficiency on farms, (1) use pressure regulators (these $13 units have saved Sustainable Solano hours of work), (2) fix leaks, (3) add spaghetti lines to direct the flow of water and (4) opt for oval-shaped hoses to reduce accidental kinks.

McDonald reiterated the standard recommended pressures are 0-30 PSI for drip irrigation and 100 PSI for sprinklers. Proper pressure management is critical for uniform water application; use a hand pressure gauge and Schrader valves to check your systems pressure, use one hand gauge to check the whole system to ensure consistent calibration. Elevation changes also impact pressure — every 2.3 feet elevation changes PSI by 1 PSI (increasing PSI when descending down, decreasing PSI when going uphill). Be mindful of the water hammer effect, a rapid change of pressure caused by quickly turning on/off valves, and look for unexplained pressure loss. Everyone should be flushing their irrigation system more often (once per year at least) and install or use soil moisture sensors for better field or lawn management. By implementing these strategies, farmers and homeowners can optimize irrigation systems for efficiency, cost savings, and irrigation uniformity.

Bill Snyder gave a presentation on a study he and his graduate students conducted on whitefly infestations attacking squash crops. In a 2016-2017 drought, potato whitefly infestation exploded. They had a theory regarding bidirectional stress on cotton plants, where the larva of the whiteflies were born and developed. Cotton plants under extreme heat stress are unable to fight off white fly infections, while populations of bugs and animals which traditionally consume these insects are also decimated by heat stress and overuse of broad spectrum pesticides. Snyder and his team found correlation between these extreme droughts and high volumes of insecticide use (per acre). In a natural experiment using center-irrigated fields and increased mulching practices, the Georgia team feels confident that the combinations of heat stress on plants and insects were a driving cause in the rise of whitefly populations. Learn more about his research here.

Sustainable Solano would like to thank the California Department of Food and Agriculture, Solano County Public Health and CHIP (the Child Health and Improvement Plan) for their support to attend the 45th EcoFarm Conference. Their support allowed us to learn so much about the state of urban agriculture, local food, and what other folks in our state, community and nation are working on. Thank you to the presenters and all the friends we made along the way.

Testing Your Soil: A Toolkit for Gardeners

Apr 26, 2024

By Patrick Murphy, Program Manager

Soil testing is an accurate and definite way to get an idea about how your soil is doing and learn what issues you might be dealing with. But what type of tests are there? What information are you looking for? How do you determine which test is best? You may want to follow a “Learn. Test. Act.” approach. Learn about the site’s history, test your soil appropriately, and act upon the test results.

Learn about your future gardening location — The test you choose depends on the history of your site. Solano County was incorporated in 1850, and the county has seen a variety of industries come and go. As such, many possible urban agriculture sites lack a robust history. Do your research before you begin:

  • What used to be near this garden space?
  • What possible sources of contamination are there?
  • What will you be growing?

You may wish to contact the local museum, or check out some online sources (see our toolkit for some suggestions) to learn more about your site’s history.

Test your soil appropriately — A variety of tests are available to everyday people and many are fairly inexpensive. The most accessible type of test is probably a “nutrient panel” (often called a “soil paste” test), which gives you an idea of the nutrient content of your soil. This will give you a breakdown of each nutrient, soil pH, salinity, etc., depending on the lab and exact type of test. You can learn more about what needs to be addressed in your garden (e.g. a lack of nitrogen, too high a pH, etc.).

The other common type of test would be some variety of heavy metal test. It is important to consider the variety of plants and produce you plan to harvest. Leafy vegetables (lettuce, kale, spinach) are known as hyperaccumulators and draw heavy metals up into their leaves. A key property of many leafy greens is their ability to accumulate heavy metals in their tissues without the traditional signs of toxicity. Do not assume plants will “reject” contamination; a significant number of plants humans consume can accumulate heavy metals in their edible areas. If you are concerned about heavy metals, such as lead and arsenic, you should test the soil you plan to grow in.

Primary Pollutant Metals-13 (“PPM-13”) and the California Administrative Manual-17 (“CAM-17”) are the standard tests to determine if you have heavy metals in your soil. PPM-13 looks for the 13 most common heavy metals, CAM-17 for the 17 most common. Either of these tests are perfect for locations where you believe there is a chance of heavy metal contamination. Additional tests exist to determine if soil has been contaminated with things like DDT, gasoline, etc. For more information about tests and costs, check out our soil contamination toolkit, or consult an environmental health specialist.

Act with the information you have — Once you have your results, decide what to do. You may have perfect soil that requires only that you begin planting. If you discover you do have a significant level of soil contamination in your garden space, you may want to consider alternative locations, remediation methods, or some combination of both. There are a number of good resources from agricultural offices and university extension programs, some are linked in our soil contamination toolkit. Always make sure the remediation technique you’re using is safe, effective, and observable. If you are attempting remediation, you will need to test your soil at regular intervals to evaluate how effective your efforts have been.

At Sustainable Solano, we have selected two potential sites that we plan to test over time to not only see what the soil composition looked like at the start of our work on these gardens, but also how our approach to building healthy soil and using permaculture practices affect the ongoing health of those gardens. We look forward to offering future updates on what this “Learn. Test. Act.” approach yields.

Grow Your Gardens and Knowledge Through Our Compost Classes

Feb 29, 2024

By Jazzmin Ballou, Program Manager

Compost happens all around us in real time. We see leaves, branches, and fallen fruit decompose back into the soil. In the winter the Earth’s energy is focused on breaking down that which is no longer alive or of use to plants, so that in the spring our soil can be nutrient-rich, and ready to use those nutrients to support the biggest production season of the year.

Soil health is a big focus for Sustainable Solano this year. This March through May, we’ll be offering classes for all levels of composting to build healthy soil. This series will consist of three classes, with a beginners composting class in March, an intermediate class in April and an advanced composting class in May. You are invited to attend the class of your choice or join us for all three to build your composting knowledge and connect with the different gardens where each class will be held.

Composting 101 – A Beginners Guide to Composting will be held at the Peace of Eden Community Garden at City Church in Fairfield. A brand-new three-bin system has just been built as an addition to this community garden, so this class is for folks who may want to compost but don’t know where to start. We’ll learn about composting basics: green waste vs. brown waste, what food scraps are compost-friendly and which aren’t, turning your pile, etc. Depending on time, we may weed or harvest from the garden so that participants can contribute to the compost bin. This class will be led by Lori Caldwell, who is not only a very experienced gardener and composter, but a very experienced teacher on those topics as well!

Composting 101 will be followed by Intermediate Compost Skills – An Introduction to Worm Composting, also taught by Lori Caldwell. This class will go over compost mishaps and how to troubleshoot bin repair, pests, etc. The time will also be used to introduce worm composting, discussing the benefits of worms, worm castings, and this compost method that is very friendly for those who want to compost but have less space to work with. The Vallejo Project Unity Garden will be hosting this class, with a worm bin and a three-bin compost system that has been paused due to pest issues and repair needs. This class will be interactive and potentially hands on, as we hope to show examples of bin repairs and give their compost system a bit of TLC.

Our final class of this series will be an Introduction to Advanced Composting Methods- Thermophilic Composting at the Vallejo People’s Garden on Mare Island. Michael Wedgley, owner of Soilogical, will teach this class, using his advanced understanding of soil biology to cover the thermophilic method of composting. As a more maintenance-intensive compost method, thermophilic composting creates an end product that is much higher in nutrients than traditional compost, as the goal is to heat up every inch of the organic matter being composted to a much higher temperature than we normally see for compost. This means it is turned much more intentionally and often, which is why after hosting this class, we will be offering opportunities for people to come back and support with the maintenance of this pile for the entire duration of time that it takes for it to break down (about six weeks).

We look forward to this ongoing process of learning about soil health and compost with you and encourage you to come ready to learn but also ready to teach! Every question asked, idea shared, comment made, in these open learning spaces feeds our own internal soils for when we are ready to harvest that knowledge and offer it back into the world, be that in our own backyard compost bins, or during a volunteer workday at a local community garden.

Sustainable Landscaping, Lawn Removal on Water-Efficient Rebate Budget

Feb 21, 2024

Thanks to everyone who came to our class in January with Alana Mirror about how she transformed her lawn into an edible and native landscape, all within the budget of the Water-Efficient Rebate Program from the Solano County Water Agency. You can read her previous blog about this project here.

For resources on how you can make a sustainable transformation in your own backyard (and on a budget!), below are individual videos covering topics from the water-efficient rebate program to DIY sustainable landscape design (or you can watch the playlist of all the videos here). You can view a PDF of the slides from Alana’s presentation here. Within these, you’ll find even more links to resources that can help you on your journey.

Sustainable Yard Transformations: Why Transform Your Lawn?


Sustainable Yard Transformation: Water-Efficient Landscape Rebate Program


Sustainable Lawn Removal: How and Why to Sheet Mulch


DIY Sustainable Landscape Design


Permaculture Principles for Sustainable Landscaping


Installing, Maintaining and Enjoying Your Sustainable Yard


You can learn more about Solano County Water Agency’s Water-Efficient Rebate Program here.

To learn how Alana’s sustainable yard transformation also transformed her life, check out her musical blog where she shares original songs, stories, and videos of her transformation at thelivingmirrorproject.org/blog

If you’d like to be part of Alana’s growing community of creative gardeners and environmental stewards, she’s offering a free online introduction to her upcoming group: HeArt of the Garden.

Whether you’re a seasoned gardener or just starting out, Alana’s introductory HeArt of the Garden two-hour, interactive Zoom event on March 23 is perfect for anyone who wants to

  • develop foundations that serve and connect with the natural world;
  • harness the wisdom of nature;
  • grow trust in your inner-compass through journaling;
  • cultivate confidence in your most honest expression; and
  • make peace with yourself, others and the world around you.

Heart of the Garden is a private online community with monthly Zoom meetings to share creative reflections, build confidence and grow connections.

For the free March 23 introductory event, you can sign up here.

Learn more about Alana’s peacemaking project at thelivingmirrorproject.org

Garden Design Templates Simplify How To Start Your Sustainable Garden

Jan 22, 2024

By Sustainable Solano

Want to learn how to apply a waterwise garden template in your own yard? Join Heath Griffith of Grow with the Flow for a Waterwise Garden Design Lab from 10 am-1 pm Saturday, Feb. 24, in Benicia. Learn more and register here.

Creating your ideal garden space can be daunting. Even with piles of garden books, maps of hardiness zones, seasonal planting charts and catalogs spread out on the table, it can take an expert eye to know where certain plants will thrive and how they will work together.

A template can be that little lift needed to get you started on reshaping your yard into something beautiful. (And the perfect activity for this time of the year when cold, rainy days staring out of the window give us an opportunity to think of spring!)

That’s why we reached out to Joshua Burman Thayer with Native Sun Gardens. Joshua is a local landscape designer and horticulture consultant who creates ecological landscape designs, has done extensive work with native plants and organic farming, and community-based work around plants and food. He wrote Food Forests for First Timers, an introductory guide to permaculture in the garden.

Joshua shared these four templates, which we are sharing with you in this blog and will include in our plant resources. These free templates give you a quick way to get started, with the basic layout and selection of appropriate plants for each design.

The templates are designed in 100-square-foot “tiles” that can be combined in various ways to create a larger design.

Joshua shared four approaches: desert, edible, Mediterranean and tropical. The desert and Mediterranean designs are waterwise and drought-tolerant, which is appropriate for Solano County summers. Below each design, Joshua offers a brief description of each as well as where in the county these options could thrive best.

Desert

Desert: For those gardeners wanting to try their luck with only minimal hand watering and no weekly irrigation, desert plants can provide a robust plant palette. These plants can acclimate in 2-3 years and then get by on 1-2 waterings by hand per month in the dry season by year 3. Desert plants evolved to withstand great solar intensity and can thrive in sunny parts of Solano County. (Vacaville, Dixon).

Edible

Edible: If you wish to maximize food production in your urban lot, the edible template will show you how to prioritize food for humans at each level of the food forest. This system takes a good amount of water and care, but can also reward with the most food per acre if water is not an issue. (All of Solano County).

Mediterranean

Mediterranean: Mediterranean plants generally do rather well here, because both the Mediterranean region as well as California are between 32 and 38 degrees N latitude and have similar marine-influenced climates. As such, expect many of the Mediterranean edibles to thrive with the seasonality of California’s wet and dry seasons. (All of Solano County).

Tropical

Tropical: Solano County residents near sea level have the blessing of being able to grow food frost-free 12 months of the year. Some winters do test that ability, but generally low lying areas near bodies of water will allow for a microclimate perfect for growing tropical crops. Try the tropical template for fun varieties to your garden. (Suisun City, Benicia, Vallejo, Rio Vista, Fairfield).

If you are interested in learning how to apply a waterwise template to your own yard, join us for the Waterwise Garden Design Lab taught by Heath Griffith of Grow with the Flow on Feb. 24 in Benicia. Registration is free, but seats are limited.
Heath got their Permaculture Design Certificate with Vital Cycles Permaculture, through a course sponsored by Sustainable Solano. Since then, they have worked with Soilogical BioSolutions and Designs, become a Qualified Water Efficient Landscaper, and earned a nationally recognized certificate in Water Harvesting. Heath is driven by a deep passion for reconnecting humans with the landscapes that live and breathe all around us, beginning with water harvesting and sustainable water use.

There are other templates out there. For native plants, we recommend the California Native Plant Society’s Regional Guides, which include plant lists and design templates. You can download the one that suits your environment here.

Have a template you’ve used? Share it with us at info@sustainablesolano.org so we can add it to our list of resources!