Join the Solana Center for a great course on how to start and sustain a school garden. As with any garden, composting plays an important role and will also be discussed in this course along with several other issues that are critical to school garden success. One of the class days will focus on a hands-on garden build, from the dirt up! Please contact Elizabeth for more information at (760) 436-7986 ext. 218 or elizabeth@solanacenter.org.


The Solana Center, in partnership with the County of San Diego, has an exciting and unique opportunity for you to expand your composting knowledge! We are offering a FREE Horse Manure Management Workshop. Learn to protect our waterways by composting horse manure! 


Saturday, January 14th
10am – 12pm
Bright Valley Farms
12310 Campo Rd.
Spring Valley, CA 91978
The workshop will be taught by Lisa Wood, known for her two long rides, totalling over 1,000 miles each. Lisa works for the City of San Diego and has published two books about her long rides. She has experience with horse manure composting on her Lakeside ranch and through her work with the City of San Diego at the Greenery.
The workshop will cover the following keys topics:
-Basic composting
-Manure composting
-Manure management
-Preventing odors and flies
-Benefits of composting
-Using your compost-Protecting local water sources
To register for this great workshop click here or call Liz at (760) 436-7986 ext. 216. Also feel free to email or call Liz with any questions. Her email is liz@solanacenter.org.
by Asha Kreiling

Gardeners love compost! A material made of yard trimmings and food waste, compost provides nutrients and beneficial micro-organisms to soil virtually for free. Compost restores lackluster soil and supports plant growth by supplying key nutrients including nitrogen, phosphorus, and potassium. Compost definitely has benefits to individual people in gardens and agricultural farms, but we cannot ignore the larger impact that compost has on the environment and the planet as a whole.

According to the EPA, Americans produced 243 million tons of municipal solid waste in 2009, or about 4.3 pounds of waste per person per day (1).  Organic materials are the largest component of municipal solid waste. Paper and cardboard account for twenty-eight percent of this number and yard trimmings along with food scraps account for another twenty-eight percent (2).

Not only does this enormous amount of waste pose a threat to landfill capacities and open space, but decomposing organic material in anaerobic conditions produces methane, a greenhouse gas twenty-one times more effective in trapping heat in the atmosphere than carbon dioxide. In 2009, landfills in the U.S. produced 12.5 million metric tons of methane – almost twice the emissions of coal mining (3).

According to the EPA, municipal solid waste landfills are the third-largest source of human-related methane emissions in the United States, accounting for seventeen percent of all methane emissions in 2009 (3). This huge amount of greenhouse gas being emitted into the air is responsible for absorbing radiation in the atmosphere, changing the climate, and severely effecting ecosystems.

In a landfill, organic materials are bagged in plastic and buried in layers of trash. Useful, recyclable materials are contaminated with regular waste and take up significant amounts of space in landfills. Decomposition occurs very slowly and the anaerobic conditions of landfills result in the large production of methane.

Composting has the potential to solve the problems of organic waste in landfills. A properly managed compost pile goes through an aerobic decomposition process. Compost allows materials to break down aerobically, producing carbon dioxide and beneficial nutrients for the soil instead of methane. Even though carbon dioxide is still produced in the process, it is a much less potent greenhouse gas.  Application of compost also reduces the need for irrigation, pesticides, and chemical fertilizers, some of which are sources of greenhouse gas emissions.

By composting organic material, landfill space is preserved, methane production is avoided, and natural soil amendment is created. So, not only does compost have benefits for our backyard gardens, but it plays a huge role in diverting waste, reducing greenhouse gas emissions, and mitigating climate change.


1 United States E.P.A., “Wastes: Non-Hazardous Waste – Municipal Solid Waste.”   http://www.epa.gov/osw/nonhaz/municipal/index.htm

2 United States E.P.A., “Municipal Solid Waste Generation, Recycling, and Disposal in the United States: Facts and Figures for 2009.”<http://www.epa.gov/osw/nonhaz/municipal/pubs/msw2009-fs.pdf&gt;

3 Misra, R.V., Roy, R.N., Hiraoka, H. “On-farm composting methods.” <ftp://ftp.fao.org/docrep/fao/006/y5104e/y5104e00.pdf>

4 United States E.P.A., “Methane – Sources and Emissions.”  <http://epa.gov/methane/sources.html&gt;

Compost made simple

What is the best way to compost?

The answer is the one that you will do every day. The goal is to make the environmental choice, the easy choice. This simply means that you will collect your banana peels, apple cores, carrot tops, lettuce trimmings, etc. in a convenient place and create a system that works for you without making you do extra work. It should become a natural part of your daily routine.

For many years I composted out of a vague sense of doing the right thing for the environment. Then I stopped because it got to be a hassle: I got tired of the smell of the anaerobic mess that I was carrying daily to the distant and out-of-the-way compost pile.  It is often too easy to find an excuse to stop doing something that we haven’t made simple enough to, if our reasons for doing it aren’t strong enough.

Now I collect my green and paper towel waste where I prepare my food, in a small container with a lid to keep out fruit flies.  The Solana Center sells a well-made, lightweight plastic countertop container with a handle and perforated snap shut lid. When it is full, I carry it outside and put it into a larger five-gallon food grade container with a screen on top, fastened with a bungee cord to keep out vermin and to allow it to breathe to help prevent it from becoming anaerobic and smelly. I learned this helpful hint at my Master Composter class.

I also supplement my personal green waste with coffee grounds from my local Starbucks. They have a great program called “Grounds for Your Garden” where they have a bin with used coffee grounds that are free to the public.  I add these to my compost pile once a week, with my 5-gallon bucket of kitchen trimmings and yard waste.

Composting is a great way to recycle the nutrients that we take out of our gardens and farms and give these valuable nutrients back to the microorganisms that feed the plants in our gardens. If we simply disposed of our vegetable scraps in the garbage, they would go into landfills, become anaerobic sludge and contribute to the the production of methane gas. In older landfills, it could also lead to the contamination of ground water. All of these side effects can be caused if we don’t take the time to compost and return a valuable resource to our garden’s soil.  Taxpayers will pay millions of dollar a year to maintain these sites long after their usefulness as a landfill has reached its maximum capacity. Ultimately, the only sustainable solution is for each of us is to take personal responsibility for our green and brown waste and return it safely to the earth through composting and recycling.

The Persian poet, Rumi, once wrote that, “In the hands of the wise, the earth turns to gold.”

Charles D. Anacker, Master Composter

The Solana Center has been receiving quite a few calls from frantic composters asking how to keep rats out of their compost bins. Compost heaps provide shelter and food, attracting unwanted pests like rats that multiply quickly and can carry disease. To help you deter these little rascals from your compost pile, here’s a few tips to keep them away.


  • Tip #1- Make sure that no grains, grease, other oils, meat, bones, fish, fat and dairy go into compost bins. These materials are odorous, break down slowly, and attract unwelcome scavengers.
  • Tip #2- Rats also enjoy eating are fruits and vegetables. Take a few minutes to dice large pieces into smaller cubes, allowing faster decomposition. You can then spread out the cubes so it isn’t easy for rodents to get to.
  • Tip #3- Make sure to add brown materials such as leaves, twigs, wood shavings or other dry carbon sources next to your bin to keep the compost heap healthy and constantly cycling.
  • Tip #4- Get some ¼ inch wire mesh and put it around the bottom and sides of your compost bin. The bottom is especially important as the rats can dig up from the ground and get into the compost from underneath.
  • Tip #5- Remember to aerate the compost regularly to also help breakdown the materials faster.
  • Tip #6- Rats prefer warm, dry environments, so remember to keep the compost moist.
  • Tip #7- Find a brick, or something heavy to keep the rats from lifting the compost lid.
  • Tip #8- Bury the new green waste a few inches from the top of the compost pile, as this helps hide the scent.
  • Tip #9- Bokashi. This is Japanese for “fermented organic matter.” Mix bokashi mix with your food scraps and let it ferment for up to 10 days and then add it to the compost pile. This will help reduce the food smells that attract pests.
  • Tip #10- Rats are reported to dislike the strong smell of mint so trying planting mint near your compost pile
  • Tip #11 – Fabric softener sheets keep rats away from an area very effectively.  This is not the most environmentally friendly approach and should be used as a last resort.

Hopefully a few of these help you to prevent or treat diagnose your rodent problems! Best of luck and keep up the good work composting!

Compost Tea

By Asha Kreiling

Compost tea is defined as a nutrient-rich water extract by brewing or steeping compost.  Compost tea can be differentiated into three types:

  1. Manure tea: a water extract of animal manure, including earthworm castings and bat guano, that can contain soluble nutrients such as nitrogen, phosphorus, and potassium but it also contains high levels of bacteria, root-feeding nematodes, and often human and animal pathogens.
  2. Compost extract: tea produced by draining water through a compost pile that contains soluble nutrients nitrogen, phosphorus, and potassium but very few beneficial microorganisms.
  3. Compost leachate: this is produced when water drains from over-saturated compost. Typically, leachate contains only soluble nutrients and few organisms. This leachate is often anaerobic which allows for the growth of certain pathogens. 1 Applying leachate from raw manure during the growing season is not recommended.9

Compost tea is used as either a foliar spray or a soil drench to promote plant growth and control foliar and root diseases. Using good quality compost will provide beneficial microorganisms and nutrients to the surface of the plant.2 When sprayed on the leaves, compost tea will immediately impact the plant and can help suppress foliar diseases, increase the amount of nutrients available to the plant, and speed the breakdown of toxins. Compost tea can be applied as a soil drench to develop the biological barrier around roots, improve plant growth, and improve soil biology in general.1 Using compost tea has been shown to increase the nutritional quality and improve the flavor of vegetables.

The University of Hawaii conducted laboratory work to study common assumptions of the use of compost tea and found that the application of tea to the root zone can increase plant yield and root growth significantly when applying a water:compost ratio of 10:1 -100:1. Soil biological activity increases with the use of compost tea. A study done by BioCycle at Ohio State University showed that the use of vermicompost tea decreased the amount of damage by spider mites, suppressed aphid populations significantly, and reduced root knot galls on tomato roots. Plants treated with regular compost tea had less substantial results.11  Aerated vermicompost tea has been shown to induce significant plant growth responses compared to nonaerated teas.10

However, a poor quality compost tea may be supplying the plant surface with unwanted components such as salts and problem microorganisms, and the presence of human pathogens is a potential hazard when consuming fresh produce.3 If composted improperly, compost can contain E. coli, salmonella, and other pathogens. If human pathogens are present even in small concentrations in the compost used to prepare compost tea and the conditions of compost tea production allow pathogenic growth, then the likelihood of contaminants being retained on foliage increases substantially when the tea is used as a spray. Therefore, control of foodborne pathogen growth during compost tea production is essential for reducing potential hazards of compost tea application. Implementing certain measures can reduce the potential for pathogens to enter compost tea.4

The use of compost tea supplemental additives, particularly molasses, stimulates plant-beneficial microbial populations, but also favors growth of human pathogenic bacteria. Studies have shown that regrowth of Salmonella and E. coli is positively correlated with molasses concentration in compost tea. 5

Aerating compost tea can breed a larger population of beneficial aerobic bacteria and fungi. Organisms consume the majority of the oxygen during aerobic metabolism, so using a bubbler to replenish the oxygen at a faster rate than what is consumed by the bacteria, the tea will remain aerobic. Aerated teas are not free of potential pathogens though, because E. coli is readily cultured under aerobic conditions. According to a study done at the Woods End Research Laboratory, if a small amount of E. coli is introduced into a tea, its population levels will decrease to the point of extinction in 72-120 hours. With adequate aeration maintenance, E. coli will not survive in the tea because of competition and predation by other organisms. These results were independent of the presence or absence of aeration.6

The Agricultural Marketing Service of the USDA advises that compost tea made without tea additives can be applied without restriction, whereas compost tea with additives should be pre-tested to produce compost tea that meets the EPA recommended recreational water quality bacteria guidelines of fecal contamination. Raw manure extracts and compost leachates may be applied to the soil with a 90-120 day pre-harvest restriction, and foliar applications are prohibited. 7

Compost tea made from aerating worm castings is best made from mature, high quality vermicompost. The material should be a fairly odorless, dark earthy compost that resembles coffee grounds. Potable water should be used when making compost tea, and all equipment used should be sanitized. As discussed earlier, compost teas brewed with additives should be used cautiously. Application to the root zone reduces risk of microbial contamination of leafy greens.High quality vermicompost tea can help promote germination growth, flowering, plant yields, and root growth.Plant diseases, parasitic nematodes, and arthropod pests such as mealy bugs, spider mites, and aphids can all be suppressed using vermicompost tea. 8

In conclusion, the quality of the compost used to make compost tea is extremely important. Using good mature aerobic compost without animal manure reduces risk of spreading contaminants into the tea brew. Application to the root zone is preferable to spraying leaf surfaces in order to maximize efficacy and reduce risk of microbial contamination of leafy greens.8 Aerated tea made from vermicompost has shown to produce the most beneficial effects on plant growth while reducing the chance of spreading disease  compared to other compost teas.


1 Ingham, Elaine. (2000). Compost tea brewing manual. Corvallis, OR: Soil Foodweb, Inc. http://www.reboreda.es/Documentos/Manual,%20te%20de%20compos.%20Edition%203.pdf

2 Ingham, Elaine. “Brewing Compost Tea: Tap your compost pile to make a potion that is both fertilizer and disease prevention.” Kitchen Gardener. Oct/Nov 2000: 16-19. Print. (http://www.wnps.org/restoration/documents/GD/GD_Proj_Notes/GD_l5.pdf)

3 Bess , Vicki. “Understanding Compost Tea.” BioCycle Jounral of Composting & Organics Recycling (2000): 71. Web. 9 Aug 2011. <http://www.jgpress.com/BCArticles/2000/100071.html&gt;.

4 Ingram, D.T., and P.D. Millner. “Factors Affecting Compost Tea as a Potential Source of Escherichia coli and Salmonella on Fresh Produce.” Jounral of Food Production 70.4 (2007): 828-834. Web. 9 Aug 2011. <http://ddr.nal.usda.gov/dspace/bitstream/10113/18297/1/IND43906748.pdf&gt;.

5 Duffy, Brion, Chester Sarreal, Ravva Subbarao, and Larry Stanker. “Effects of molasses on regrowth of E. coli 0157:H7 and Salmonella in compost teas.” Compost science and utilization 12.1 (2004): 93-96. Web. 9 Aug 2011. <http://cat.inist.fr/?aModele=afficheN&cpsidt=15598691&gt;.

6 Brinton, W., P. Storms, E. Evans, and J Hill. “Compost Teas: Microbial Hygiene and Quality In Relation to Method of Preparation.” Journal of Biodynamics 2. (2004): 36-45. Web. 9 Aug 2011. <http://www.woodsend.org/pdf-files/compost-tea-BD04R.pdf&gt;.

7 National Organic Standards Board. “Compost Tea Task Force Report” (2004).                < http://www.ams.usda.gov/AMSv1.0/getfile?dDocName=STELPRDC5058470&gt;

8 Radovich, Ted, Archana Pant, Nguyen Hue, Jari Sugano, and Norman Arancon. “Promoting plant growth with Compost Teas.” Food Provider Mar-Apr-May 2011: 1-3. Web. 16 Aug 2011. <http://www.ctahr.hawaii.edu/sustainag/news/articles/V7-Radovich_etal-CompostTea.pdf&gt;.

9 Nikolic, Jovan. “Overall study of compost water extract application though fertigation system in organic farming.” Jul 2003:Web. 16 Aug 2011. <http://orgprints.org/6661/1/JovanNikolic03.pdf&gt;.

10 Arancon, Norman, Clive Edwards, Richard Dick, and Linda Dick. “Vermicompost Tea Production and Plant Growth Impacts.” Biocycle Nov 2007: 51-52. Web. 16 Aug 2011. <http://growingsolutions.com/shop/images/bc0711_51.pdf&gt;.

11 Edwards, Clive, Norman Arancon, Eric Emerson, and Pulliam Ryan. “Suppressing Plat Parasitic Nematodes and Arthropod Pests with Vermicompost Teas.” Biocycle Dec 2007: 38-39. Web. 16 Aug 2011. <http://growingsolutions.com/shop/images/bc0712_38.pdf&gt;.

Do you have too many slugs in your compost bin?

In a spray bottle, mix in 1 cup ammonia to one quart water. Go out at night and spray slugs wherever you find them.  Ammonia will have no affect whatsoever on your compost.  It will only kill slugs and snails.  If you go slug hunting in daylight, check under rocks, pots and lids, any dark moist hiding place.  You can somewhat trap them by placing said hiding places in proximity to the bin.

Even though slugs contribute to decomposition, they tend to stray from the bin into the garden.  Many people find this unsavory, so if you have too many slugs, fill up your ammonia sprayer and take it to ’em.