–Garlic, “Georgian Crystal”
Don’t forget—our fall festival is coming up this Sunday, September 25th from 3pm until dark. We’d love to have you out to the farm for yard games, jumping in mud puddles, farm tours, and a potluck starting around 5pm. Please bring yard chairs, table settings, a dish to pass, and footwear that won’t mind a little mud. Ok, a lot of mud…. Friendly dogs are welcome, politicians are not.
This week we finally welcome back head lettuce after much too long of a break. Between plantings that were eaten by deer, other batches that didn’t germinate well, and others that were flooded out, we’ve certainly been missing good salads lately. This week we have one of my favorites and perhaps the best tasting variety, called “Nevada.” After a few weeks of nothing but kale salads, we were all salivating over dinner tonight with the return of a nice crispy lettuce salad. Next week we should have arugula ready to go before we finish out the season with some welcome loose-leaf salad mix. I had also planted a good crop of spinach, but unfortunately the seeds all rotted in the soil during our really rainy August. I had a total of eight plants germinate (out of about 5,000 planted), so unfortunately we’ll have to wait until next spring to try spinach again.
One experiment that I’m looking forward to is overwintering spinach. This spring I made some much-needed upgrades to our greenhouse (where we start nearly all of the plants that end up in the garden and eventually in your CSA box). I needed a heat system of some sort to help keep things alive and happy in the frigid nights we still often get in April and May, and I was looking to do it for as little money as possible. After researching the options for greenhouse heat, I was most struck by the idea of compost heating. Since I need a lot of compost for the fields anyways, this is a way to both make compost and utilize the heat by-product.
Back in early April I made a large compost pile out of old straw, grass, alfalfa, wood shavings, dirt, kitchen scraps, and several hundred gallons of water. The whole pile is fifteen feet in diameter, six feet tall (at the beginning of the year), and surrounded by straw bales to help keep the heat in. The compost shrunk to about 3-4′ in height after the contents broke down, and the end result is compost of very high quality that I didn’t need to turn.
But the insight I gained from research is harnessing the heat by-product of the compost pile. My pile hit 130 degrees inside (at which point my thermometer ceases to function until it falls below that mark) even on a 40 degree cloudy day in April. What other folks have developed is a system that circulates water through the compost pile, sharing some of the heat naturally produced by micro-organisms breaking down compost. So I connected 800′ of radiant floor tubing and ran it in circles all through the compost pile. One end of the tubing has a pump that pulls the water out of the compost pile (at 90-100 degrees) where it runs through more radiant floor tubing in the greenhouse. After stretching for 600 feet in the greenhouse, the water inside is now around 70 degrees and gets forced through the beginning of the coil in the compost pile. This endless loop ensures piping hot water around the clock. The only carbon emissions come from the simple pump, which doesn’t draw much in energy. Certainly nothing compared to a propane water heater or an on-demand electric heater.
Even after all of my research into the process, I could hardly believe it when it worked. It’s hot water, heated in just seconds, with no carbon footprint. And it also works in the greenhouse. The hundreds of feet of heated tubing make a huge difference in the greenhouse at night. On one April night when it dipped to 22 degrees outside, the greenhouse air temperature stayed above 55 degrees with no heat source besides water that had quickly passed through a compost pile.
Now that I have the system set up, I’m hoping to experiment with winter production in the greenhouse. The only downside is that the materials I used are fully composted by now and are no longer producing heat. But assuming I get my act together and get another pile built, it’s likely I could provide heat for the greenhouse all winter long. If so, I can plant spinach and kale right into the dirt flooring of the greenhouse (the heat tubing coming from the compost pile passes just below the surface of this soil, so it’s extra toasty) and harvest greens all winter long. This is still theoretical, but it’s definitely an exciting option for year-round production even this far north. I’ll let you know how it turns out!
Expected next week: Cabbage, arugula, onion, broccoli, rutabaga, sweet pepper, garlic, and tomatoes.
Curried Celery Soup: https://foxandfawnfarm.com/2014/07/16/curried-celery-soup/
Humble Vegetable Casserole: https://foxandfawnfarm.com/2010/07/16/humble-vegetable-casserole/
Bok Choy Yuke: https://foxandfawnfarm.com/2012/06/21/bok-choy-yuke/