Are there any plans for collecting compost in the future?

The limiting factor on that right now is that there is no facility within reasonable driving distance of the city that can handle the kind of volume of food scraps that we’d get if we had a curbside collection program for residents. There are a few private companies that are moving forward with plans to build new facilities for the Boston area, so that needs to come first. We need a facility that can process yard waste and food waste together, similar to the way that the San Francisco and the Seattle programs work. The programs in place for businesses and for the drop-off program, that food waste is being taken to farms that are basically at capacity. They can’t handle the kind of volume that we’d get with the curbside program.

What farms are they being taken to right now?

There’s Rocky Hill Farm in Saugus and Brick-Ends Farm in Hamilton. They’re large-scale facilities, but they’re small when we’re talking about providing collection to everybody in Cambridge. I’ve estimated that we’d see at least 3,000 tons a year; it could be three times that. The food waste drop-off program is basically 50 tons a year—we’d be doing about 50 tons a week.

The farms are doing outdoor composting in windrows, long piles they turn every day. It would be impossible, I think, to site an outdoor composting facility in the Boston area. You’ve got neighbors and odor concerns. So the companies are looking at this technology called anaerobic digestion, where you can do composting indoors in an environment where there’s no oxygen, and they can capture the methane that is emitted during that composting for electricity or fuel. The city of Toronto has a few of these, and it’s very popular in Europe in urban areas.

The city is watching what the private sector is exploring. Casella Recycling, is looking at anaerobic digestion, as well as Save That Stuff, a local hauler. There are a few other projects that are being considered.

I think within the next two to three years we’ll be in a better position to consider curbside organics collection. We’ve had the drop-off program for residents for two years, and businesses have had the curbside organics for four years. We get a lot of questions about this, and I hope we will be in a position to offer it.

The best option, of course, is to try to compost at home. If you have backyard space, DPW sells compost bins for $50. Apartment dwellers can compost indoors with a worm bin.

If you’re not sure whether something is recyclable in your town, is it better to toss it in the bin for them to sort at the center or should you just not include it?

Well, the top items that are not accepted are food, plastic bags, Styrofoam, VCR tapes, liquids, and light bulbs. We don’t take glass dishes or cups, and no plate glass, like picture frames or windows, which can be leaded glass. Currently no pizza boxes, but the new program is going to accept empty pizza boxes. Other than those items, we do accept a lot of materials: all paper, all plastics, glass bottles, metal can, and cardboard. With the new program, any stiff plastic will be accepted, even if it doesn’t have a number on it.

Ultimately, if you’re not sure, I’d say, “When in doubt, throw it out.” But call or visit the website and check. The big no-nos are plastic bags and food waste.

Anything else about the program that you want to share?

I’d love to get the word out about the recycling tours. We’ve got one a month: September 29, October 28, and November 18. They’re open to the public, and it’s a really great way for people to see the recycling process in action and feel confident that what they’re putting in their bin is really getting sorted and sent to companies to be made into new products. Recycling is real, and it’s an important industry in our economy. We have a six-minute video on our website of the recycling processes in Charlestown, so if you can’t make the tour, you can also watch that. To sign up, e-mail recycle@cambridgema.gov or call 617-349-4815.

One year ago: My Biggest Environmental Sin.

• Mix compost directly in with potting soil or sand. The ideal ratio is 1:5. Don’t use much more compost than this or the soil will retain too much water and the plants’ roots will rot. This is exactly what happened the first time I tried this a couple years ago.
• Steep the compost in water and use the resulting “tea” as liquid fertilizer. Mix two tablespoons of compost per liter of water and let it stand for a day.
• Put a layer of compost on top of the soil. Same idea as the previous one, but it’s less work. It also retains moisture like mulch, but might actually encourage weeds.

Basil, dill, and chives

For the herbs that we planted, we mixed compost directly in with the potting soil. I don’t know if it’s the compost or all the rain we’ve been getting lately, but they’re going nuts. It’s hard to use them as fast as they grow. Unfortunately, some sort of sprouts that were seeds in the compost are popping up, too. I actually have to weed my potted plants!

It obviously wasn’t the ideal environment for the poor worms; the few dried-up bodies on the floor around the bin were a testament to that. The compost is too compacted because we haven’t been turning it, and too moist because we haven’t been adding paper to absorb the water. But the worms are still doing fine. In fact, they’re huge, and there are tons of them!

Worms love curling up in eggshells and laying cocoons.

There are even worms left in the old bin, the one we stopped feeding in September because it was “finished.” Now it’s really finished, maybe overly so. We’re going to pick the worms out and add them to the current bin. Once we get rid of the compost, we can start fresh and have two bins going at the same time.

There probably aren't even any nutrients left in there....

But from now on, to prevent another fly infestation, I’ll freeze all my scraps before putting them in the bin. Another method of killing fly eggs is microwaving, but I think I like freezing better.

I’m so glad that we can use our worm bins again—all the scraps building up in our fridge were gross and all the trips to Whole Foods to get rid of them were inconvenient. And I love playing with my wormies.

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Not feeding that bin for a couple months has completely eradicated the fly population living in the compost. Unfortunately, it looks like they’ve all moved to the new bin.

This is so embarrassing! I swear I’ve never had a fly problem before. We’ve been keeping the flies out of the rest of the house by storing the fruit in the fridge and the dirty dishes in the dishwasher, and putting out cups of apple cider vinegar.

To get rid of them completely, we’re going to stop feeding the new bin for a few weeks. It takes fruit flies 10 days at the most to mature from larvae, and as we’ve seen with the old bin, the worms can survive (even thrive) far longer than that without new food.

We’re also going to add a fly trap to the bin. We’ll make one by putting an apple core in a jar, snipping off a corner of a Ziploc bag, and attaching it to the mouth of the jar with an elastic. If we kill as many adult flies as we can and withhold food so they don’t multiply, we could solve this problem.

To prevent it in the future, from now on we’re going to freeze all of our scraps before adding them to the compost. That’ll kill any eggs that might stow away on fruit peels. Wish us luck!

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To harvest the compost, we first emptied the bin into piles. Worms automatically move away from light, so they congregate at the center of each pile. Then you can easily sift through the compost until you get to the ball of worms in the center. Okay, maybe not easily—it took three hours for Jason and I to get through it all. It could have been a lot faster, but we were stopping to pick out every one, rather than tossing them into the new bin en masse.

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After weighing the worms, we added them to the new bin, already filled with newspaper and food scraps. (Thanks for your contribution, Sharon!) We tore the newspaper into strips this time, rather than putting it through a shredder, in the hopes that the larger pieces will discourage the worms from munching on their bedding. Then we wet down the newspaper so the worms could breathe. (Very important.)

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The old compost wasn’t completely broken down yet (and, in fact, had a few pepper sprouts growing in it), so we left a few little worms and some cocoons behind, to finish it up. I feel bad sacrificing them, but I think we’ve rescued more by starting the new bin now.

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There was one casualty. Oliver snapped up a particularly adventurous worm before we could stop him. You should have seen him jump when it moved in his mouth!

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The enemy

The culprit was probably a melon from my fruit salad last week. (The seeds from the cantaloupe are the only things still recognizable in the compost, except for those darn cabbage leaves.) Not only did they attract fruit flies, but they made the compost too moist. Note to self: a balanced diet includes fruit and vegetables—for worms as well as humans.

So after we buried our food scraps this week, we piled on tons of shredded newspaper. It’ll absorb the water and (hopefully) prevent the flies from getting down to the food. We also put a small bowl of vinegar on top of the lid. We’ll see if that does them in. Flies are notoriously hard to get out of worm bins.

In any case, I think we’ll be harvesting the compost next weekend. The worms are eating everything so quickly that we’re having a hard time keeping up with them, and their waste to bedding ratio is out of whack. I think we’ll transfer most of them to a fresh bin, piled high with newspaper and food.

We’ll leave a few worms behind to put the finishing touches on the compost, but we won’t feed them anymore. As long as we keep the whole thing far away from the new bin, that should starve out the flies. I hope. I’ll keep you posted.

I think corn plastic is just greenwashing, because, while it can technically be composted, only a tiny tiny percentage of it actually will be. Most of it will end up in landfills, where, without any oxygen, it won’t break down any more than other trash.

Not only that, but it won’t break down in my worm bin or in your backyard compost, either. It needs temperatures of 150 degrees Fahrenheit, which is only reached at large commercial composting facilities.

Here in Cambridge, we can take it to the Department of Public Works or Whole Foods for composting, but I doubt most towns have such options. So even most of the people who would compost it, can’t. It’s just misleading.

And while #7 plastics (the catchall “other” category that this falls into) are accepted by Cambridge for recycling, corn plastic in particular may not actually get recycled, because there’s not a large market for it. For that reason, most towns don’t even accept it in recycling bins.

Of course, we all agree that petroleum is not a good option, but neither is industrial corn farming. And at least regular plastic can reliably be recycled. So I think until municipal composting becomes commonplace, corn plastic just seems pointless.

Isn't it adorable?

I find this reassuring, because it means that their environment is good enough for them to reproduce; it’s not too wet or too dry, the castings to paper ratio isn’t too high, and there’s enough food. In fact, I think they can handle even more garbage than what we’ve been giving them, since everything but the hardest veggies (cabbage leaves, celery) is completely unrecognizable by the time we feed them again.

You can tell this one is about to hatch because of the reddish-brown color.

These worms are so much more efficient than the first batch that I feel we really must have mistreated the first ones (before we killed them). We didn’t know that much about worms when we started out, just what we’d found out from some online research. At the time, I thought they were working out okay. They ate our garbage and they reproduced, but they did both very slowly compared to the new ones.

And the parents. Aren't they huge?

I think our problems were:

1. We used regular paper instead of newspaper. Apparently, the newspaper absorbs more water, and I’m told soy-based ink (Boston Globe, New York Times) is less toxic to them than regular ink.
2. We didn’t let it get wet enough. We knew moisture could be a problem, because if it got too wet they’d make a break for it. But we didn’t know that they needed a certain amount of moisture to allow them to breath through their skin. I think we slowly suffocated them.
3. We let their poo build up too much. We didn’t know exactly what finished compost should look like, so we waited and waited until it looked like potting soil. Unfortunately, that meant that they were living in way too much of their own filth, and that’s what eventually killed them. This is actually a legitimate way to compost, if you’re looking for castings to add to your potted plants and don’t care if your worms survive.

This time, determined to do it right, we read a book on the subject (Worms Eat My Garbage) and went to a (free) class at the Somerville Community Growing Center (a great place—you should check it out). Now we’ve got a second bin all set up to transfer most of our worms into when this compost is almost done, and it seems like it’ll only be a few more weeks. These guys work fast!

What we need is a regular compost bin, where the temperatures get so high that everything breaks down. But we don’t have space for an outdoor bin. Luckily there are other options around.

The City of Cambridge offers compost drop off at the DPW lot Tuesday and Thursday nights from 4:00 p.m. to 7:30 p.m., and Saturday from 9:00 a.m. to 4:00 p.m. That time frame can be a little tight for us, though.

The DPW has also partnered with the Whole Foods on Prospect Street. We can drop off food waste in the toter at the back of the parking lot every day from 8:00 a.m. to 10:00 p.m. And unlike our worm bin, this compost can include meat and dairy products—even greasy pizza boxes.

They're pretty clear about what can and can't go in, too.

We used to collect our scraps in a pretty Williams Sonoma compost bucket, but it tended to smell and collect flies. So now we use a couple of large Tupperware containers (with tight covers) and store them in the refrigerator. It’s kind of funny when we haven’t gone grocery shopping in a while to look in there and see more garbage than food!

We keep the composting food under a moist layer of shredded paper.

To make the easiest sort of worm bin, drill holes into the top of a large Rubbermaid container—the more the better, since you want the air to circulate. Fill it 1/2 to 3/4 full of shredded paper. I hear newspaper works best, but I’ve always had good luck with regular paper, too. (And it’s a good way to get rid of all those credit card offers that you don’t want to leave out in your recycling bin.) Be sure to moisten the paper, but don’t soak it. Worms breathe through their skin, and they need water to do that, but if they’re swimming, they’ll either die or try to crawl up the side of the bin. Bury your fruit and vegetable scraps (no animal products), making sure they’re completely covered by bedding, and add your worms.

Our bin was getting a little too wet, so we left the new top layer of paper dry this time.

Earthworms don’t work, so you can’t just dig up any old worms and put them in your bin. You need to get red wigglers, because they live in the leafy litter of the forest floor, which is much like the bedding you’ve made. The first time we did this, we got a pound of worms through the mail, and they came all wrapped around each other in a ball. The second time, we just went to Arlington Bait and Tackle. So far (one month in) they seem to be bigger and eating more than the mail-order worms, so I’d recommend that. Just make sure you ask specifically for red wigglers.

Aw, isn't he/she lovely?

Those are the basics. I could go on for days about what sorts of food they like best, how often to feed them, how/when to harvest the compost, and why we killed our first binful of worms (oops), but this is getting kind of long. I’ll save that for another time.