Friday, April 30, 2010

Vermicomposting for school cafeteria

For the volume of food typically produced by a school cafeteria food preparation (15-20 pounds per week) you'd need 35-40 pounds of worms. To try to keep costs low, you could start with 30 pounds of worms, which is on the low side and would still cost around $510 (not including shipping), and see how it goes (probably throw some food away in the beginning weeks-- especially citrus & onions).

Because this cost is generally too high, it be better to use a combination of vermicomposting and hot composting. You would start with 2 composts bins: 1 4'x8'x18" bin with worms (20 pounds of worms) and 1 4'x4'x4'  hot compost pile without worms. You could feed the worms the correct amount of food per week and put any overflow food in the hot compost pile. Over the summer, only feed the worm bin (feeding 10 pounds of food per week the first two weeks and increasing by 1 pound every week thereafter). When you have filled the hot compost pile (or at the end of the school year) don't add anymore food and just turn the hot pile over the summer. When school starts harvest the hot compost and split the worms into two 4'x8'x18" bins (probably 20-25# each-- they will have doubled after 10-12 weeks). Then your worms will be sufficient to handle the food additions.

You will have to be very careful to BURY the food you add to prevent fruit flies. Even if you are careful, you may want to consider having fruit fly traps (vinegar traps and sticky traps) around just to be proactive about potential problems. It is very easy to have flies on the food in these large collection containers (and in the food) before you add it to the worm bin.

Consider the location of the worm bin carefully. I do not suggest these bins be located in classrooms or near kitchen area. If your worm bin will be outside in Maine then most (if not all) of your worms will die next winter when the bins gets too cold (sustained soil temps at or below 35F). Your bins can be   insulated or warmed to keep soil temps above 40F (to keep worms alive) and above 65F (to be able to add food). Alternatively, your bins can be located in a sheltered area (perhaps a trash collection room or area) where soil temps will be maintained above 65F.


Sunday, April 18, 2010

Thoughts on Weeds

What are weeds? A weed is a plant that is growing where you don't want it. I don't know how first coined that, but it works for me.

Most people think of noxious weeds when they here weeds. Noxious weeds would include poison ivy, thistle and other things that can hurt. I would also consider invasive plants, like purple loosestrife, noxious. I include noxious weeds in this discussion. Poison ivy or thistle growing away from where people contact it is no bother.

In general, weeds can be used to tell you something about soil conditions in the area they are growing. For example, plantain in your lawn is an indicator of acidic and compacted soil. Catchweed and chickweed are indicators of healthy soil with high organic matter (e.g., in a vegetable garden, cold frame or greenhouse). This should also tell you that just changing soil conditions to be optimal for what you want to grow will NOT prevent all weeds. Nevertheless, you can use the weeds in your yard as a soil indicator and, in some instances, change the soil to be more favorable to what you want to grow and less favorable to what you do not want to grow. To understand what your weeds are telling you, I suggest a reference book. I use "Weeds of the Northeast" as my source of information. This book has great photos of the lifespan of the plant (helpful for identification) and plenty of information on habitat. I supplement this information with my frequent yard reference: "Rodale's Chemical-Free Yard & Garden: The Ultimate Authority on Successful Organic Gardening".

Ask any organic gardener and you will hear that the key to weed prevention is understanding the weed biology (see above) and controlling weed seeds. Preventing weeds begin with controlling the seeds. If you notice a weed, I suggest that you first remove any flowers or seed heads, then identify what it is and what it is telling you and remove the plant. If it propagates by rhizomes as well as seeds (e.g., red sorrel), be sure to carefully remove those also.

Controlling weed seeds begins in your yard, but also extends beyond your property to upwind areas (wind-borne seeds), animal habitat (viz. seeds transported by birds) and your source of new plants or soil (are you bringing weeds home from the garden center or spreading them with your compost?). Also, realize that seeds can remain dormant in soil for years. Cultivating a new patch of ground can expose seeds that were buried there years ago. All of these other sources of weeds should be kept in mind when you're in your yard.

When you are removing weeds from your yard, remember that some weeds can be eaten. For example spring dandelions make great addition to mixed green salads and you can make wine from the flowers. Eliminating weeds by eating them is good for you (assuming you are not spraying them with something nasty) and feels like justice! There are several excellent references for identifying plants in your area that can be eaten:  Stalking the Wild Asparagus and Foraging New England: Finding, Identifying, and Preparing Edible Wild Foods and Medicinal Plants from Maine to Connecticut.  Many of the plants in these texts include weeds. One word of caution, be sure you KNOW what you are eating (positive identification) and that it was not sprayed with weed killer (I doubt that is an issue if you are reading my blog!).

The goal of organic gardening is not complete domination and the absence of weeds, rather your goal is to stay ahead of the weeds and do what you can to eliminate the noxious weeds and reduce the seed bank of the others. Over time, you will minimize the seed bank of weeds in your yard, optimize conditions for the plants you want to grow, and achieve balance in your yard.



Saturday, April 10, 2010

Your actions and choices can save the world, but what helps most?

I recently read a book by the Union of Concerned Scientists "The Consumer's Guide to Effective Environmental Choices ".Written in 1999, the practical advice and suggestions offered in this book make sense more than 10 years later.

Here are my take-away messages from reading this inspiring book.

First some high-impact activities that should be avoided:
1. Limit use of unregulated off-road transportation. Off-road engines (boats, ATV, dirt bikes) are frequently less regulated than cars and trucks,so their per hour emissions are much greater. Look for opportunities to limit use of these and replace old, unregulated engines with cleaner and more efficient choices
2. Reduce use of gasoline-powered lawn equipment. Like off-road engines, gasoline powered tools are often overlooked as sources of air pollution. Use these tools sparingly and choose cleaner options when possible.
3. Replace old wood burning stoves with cleaner/more efficient models. Regular fireplaces and older wood burning stoves are not very efficient and can contribute to air pollution. (The EPA provides more information and
4. Stop using hazardous chemicals, cleaners, and paint. (Choose less toxic or hazardous products wherever possible. This includes pesticides and herbicides!)
5. Avoid products made from endangered/threatened species. (This is very obvious so to that list I would add non-sustainable products)

The authors also recommend practices that consumers should do to help the environment. These are common sense steps and practices that are worth reviewing:

Transportation. Drive less: combine trips and walk/bike/mass transit/carpool more. When replacing an old car, choose a fuel efficient model (think in terms of gallons per hundred miles, rather than miles per gallon).

Food. Eat lower on the food chain (less meat, more veggies). Buy local or organic whenever possible.

Home and Office. Make your home as efficient as possible (insulate and prevent air leaks; install programmable thermostats; use low-flow shower heads and toilets; maintain your heating system; and consider upgrading heating system or appliances to more efficient model if more than 15 years old). Choose an energy supplier that offers renewable energy.

Give special attention to major purchases. Major purchases (automobile, home, appliances, energy offeror, etc.) are your opportunity to make a larger difference and drive the marketplace to offer more environmentally-responsible choices. You are voting with your dollar whenever you choose to buy products that are better for the environment.

Don’t sweat the small stuff. Think about the items on this list and focus on those. Then try to do more (reduce/reuse/repurpose/recycle), but don’t stress if can’t or forget. For example, if you forget to bring a reusable bag when you shop, just reuse/recycle the bag you receive. Don’t beat yourself up about it!

Get involved. What can you do to help spread the word about how you feel and what you have learned? You may want to be a leader in your community, be a grassroots member (contacting elected representatives and other people), or teaching young people or adults formally through after school or continuing education programs or informally to your family, friends, and neighbors. These will also put you in touch with like-minded people from whom you will learn about other things you can do or try.

I know it can be daunting when we read the news and research reports concerning the environmental problems. However, we can all make changes to turn things around. I choose to see this as a series of opportunities to make a difference, rather than an impossible mountain that must be overcome.



Friday, April 2, 2010

Natural lawn care: preparing and timing top dressing with compost

I have been pursuing an organic lawn for 10 years. I must admit that until a few years ago, it was not going too well. I would amend my soil based on soil test results, but it was not producing a consistently healthy lawn. Note my objective here is not a golf course-like monoculture of lawn perfection, but a demonstration that organic lawns can be healthy and nice looking with a similar outlay of money as chemical-based lawn care. I have recently, in the past two years of two, been surprised by my results. The change was the result of going to a presentation by Paul Tukey and then reading his book "Organic Lawn Care Manual".

Paul recommends several steps in his book, some obvious and some not. One of the obvious suggestions was to use compost tea to increase the microbial life in the soil. Vermicompost tea is the immediate choice for me. Also, using a grass seed that is low maintenance and hardy in your climate. His recommendations made sense to me, so I decided to try it. After a few years of doing it, I am a believer and I have learned a few things. For your information and comparison, I am including sources and prices in this blog so you can see what I spend on supplies and tools.

One of Paul's not so obvious recommended changes was to top dress the lawn with compost. You overspread the grass with a thin layer of compost-- not so much you smother it! This compost filters down into the turf and eventually reaches the root level. When I stared, my lawn was growing in 2-3 inches of topsoil above sand. There was no way grass would thrive when it could not root deeply.

The other recommendation was to use gypsum instead of lime to increase pH (my soil test told me my pH is still a bit to acidic). Gypsum has calcium rather than magnesium as the cation salt. Calcium prevents soil compaction whereas magnesium promotes soil compaction. I prefer pelleted gypsum because it is easy for me to spread it by hand. According to the results of my soil test and the recommended application rate, I applied 5# of pelleted gypsum. Before you start making changes to your lawn care program, I suggest you contact your local cooperative extension to get a soil test kit. Standard tests for lawn (turf) is $15 plus shipping. That's around $20 for a detailed analysis of what you need to do to address deficiencies in your soil.

Some people like bagged compost, but I prefer to get bulk local organic compost ($203.80 delivered for 4 cubic yards*) and supplement with some (about 1 cubic foot*) of my vermicompost (FREE!). Bulk compost is cheaper and does not make such a mess of the car, but you have to move it around with a garden cart instead of carrying bags.

*Why 4 cubic yards? My total lawn area is a little less than 5000 square feet. If I assume 1/4 inch of compost on the entire grassy area, I will need 104 cubic feet to cover (5000 square feet x 1/12 inches to feet x 1/4 inch depth).4 cubic yards is 108 cubic feet, plus my 1 cubic foot of vermicompost = 109 cubic feet. That is enough to do the job.

The objective here is to add organic material to the soil and correct any nutrient deficiencies while adding more grass seed to fill in any bare areas.

First thing you need to do is prepare the soil. I do this by raking off the dead grass, any stray leaves, and sand from winter and then core aerating. Several years ago I tried powered aerator that I rented and swore I would NEVER do that again. It was a heavy intractable beast that I could not safely control. I found a manual core aerator that is slow but safe. I received a pair of those spiked shoes several years ago and think they may be better for killing subsoil grubs than for aerating. The core aerator leaves little tubes of soil on the lawn that break down. You can rake and core aerate a few days before seeding and overspreading the compost.

The day I overspread the compost, I also over seed with Allen Sterling and Lothrop's Tuff Turf grass mix and white clover ( I use a mix of 9# Tuff Turf to 1# white clover ($22.50 and $8.25, respectively). I don't actually mix these (the clover seed is much smaller than the grass seed). Instead, I hand cast each over the area of my lawn after raking and core aerating, but before I spread the compost. I've gotten pretty good at hand casting, and I trust it more than the mechanical spreader that I can never get just right. At this time, I also hand cast the gypsum. I purchased gypsum locally for $6.03.

I add white clover to ASL's grass seed mix because I do not consider clover to be a weed. Chemical lawn care propaganda that clover is a "broadleaf weed" is a convenient deception that is based on non-specificity of herbicides and promoting a lawn that is dependent on external inputs (i.e., nitrogen fertilizer). Clover fixes nitrogen (i.e., free fertilizer from the air), and I think it looks nice in the yard. (Pardon me while I step down from the soap box.)

I prefer to move the mixed compost with my garden cart and a shovel. Then I spread it around and break up any clumps with the back of a bamboo rake. The objective is not an even layer over the lawn that you rake in and it goes away. Nope. Instead it is a somewhat uneven layer of compost that is hidden in some areas and really visible in other area.

My tip is to try to time the seeding and overspreading to happen right before a big spring rain event. The rain will water in the compost that is on top of the soil. To get good germination of the grass seed, you want soil temps at least 50F. This is a sweet spot in the year that you can hit if you watch your lawn soil temp with a soil thermometer and keep an eye on the weather.

This year I timed it to finish last weekend (just before our big rain this week).

I will post some photos so you can see that after 2 weeks the compost is gone and the lawn is green. I will periodically water the lawn with vermicompost tea, but I never water during the dry periods we sometimes get. The lawn goes dormant and then I don't have to mow (hooray!).

In time, I hope to build up enough soil under the lawn (6-8") to not have to add compost (3-4 more years at my current application rate), and I am only adding gypsum until the pH stabilizes to a higher level than it is now. At some point, I hope to have to only rake, over seed bare spots and core aerate.

Yes, this is a lot of work. And it takes time to wean your lawn off of chemicals and bring life back to your soil; however, it will pay dividends this summer when you do not have to weed, water, or fertilize. As oil becomes more expensive, petroleum-based fertilizer and herbicides will only become more expensive. Your lawn is an ecosystem that you can nurture using organic methods and free yourself from the expense and danger of chemical lawn care. I hope you try it.

By the way, my total outlay in money (I have the tools I need already) was $260.58 (soil test, 4 cyds of compost, grass and clover seeds, and 5# gypsum). I used all the compost, clover seed, and gypsum. I have approximately 3/4# of grass seed left to patch as needed this summer. That is all the money I will spend this year on my lawn (not counting electricity and a few tablespoons of molasses to make vermicompost tea). I could top dress again in the fall, but I typically don't.

By the way, you can always recruit a helper to make the job go faster...
Kate is using the metal rake. She found that easier for her. I prefer the width of the bamboo rake.

April 5 update: Here is a photo of the lawn after 1 week (below). As you can see, the compost is making its way down into the turf.

April 12 update: Here is the lawn after 2 weeks (below). All the compost has moved down and the grass is a nice healthy deep green.

For more information see:  OR



nb. Terry Soloman (formerly of Vermont Compost) suggested I try core aerating after I overspread the compost (to work it into the turf and soil better). I have not tried this method, but I would welcome your thoughts on this.