Here at the Garden we don’t see a reason to call it quits just because it’s cold outside.  We have some experience, structures, equipment and techniques in our arsenal to help us extend the growing season, and they have been so successful that we now can garden all winter long.  One technique is simply growing crops that are tolerant of freezes, and so we are utilizing the outside beds to grow winter cover crops of rye and vetch.  In the more substantial shelter of the hoop house we have delicious cool season vegetables like Kale, cabbage and kohlrabi seedlings planted and growing.  The hoop house is not airtight and loses heat at night, so we also have sheets of frost cloth that we drape over the rows in the evening, adding an extra layer of insulation till the sun comes back up.   The greenhouse however is where most of our growing power is happening this winter.

In the greenhouse, the lettuce tables and the Aquaponics array are the current growing champions; they are producing the most out of everything at the garden right now.  The lettuce tables are frames of 2×4 lumber with fine gauge wire stapled to the bottom and are filled with a few inches of soil.  The lettuce seeds get sprinkled on top, lightly covered and watered in.  They are placed above warm growing mats, which speed germination, and we can harvest delicious baby greens in as little as 5 weeks, and have done so several times already.

The aquaponics array is a project we have been experimenting with for about 6 months.  It is a mixture of Aquaculture, the raising of fish, and Hydroponics, the growing of plants without soil. The system could have a whole blog post to itself, but a simple way of explaining it is the plants and the fish grow in the same water, with the fish providing the fertilizer for the plants, and the plant roots cleaning and filtering the water for the fish.  There are many different plants growing the in the system, including lots of different types of lettuce, strawberry plants, kohlrabi, and watercress.   While none of the fruiting plants have produced (yet), we have harvested greens and watercress several times.

Also coming along in the greenhouse are some cool weather seedlings, currently growing on warm mats next to the lettuce tables, and we will grow them in small pots till the late winter months, when it tends to warm up around here and we can pop them into the ground for an early start on the spring season.

Growing all these plants would not be possible in the winter if we didn’t take advantage of free heat in form of the sun, and the greenhouse does a good job of letting the heat in and holding it there.   Even on cold days when the sun isn’t shining it stays a little warmer than the outside, and on sunny days it can be 30º or higher than the outdoor temperature.   We also have a couple of 50 gallon barrels, painted black and full of water, that absorb the heat of the sun during the day and let it out at night, a concept known as passive heating.   Besides the plants, something else that benefits from the warmer temperatures in the greenhouse is the composting worms.  They live in a cedar-lined trench underneath one of the lettuce tables, and stay very busy composting coffee grounds donated by local coffee houses, juicing scraps donated by a local smoothie boutique, and our own leftover garden scraps.  Worm castings are garden gold, and we will collect from the bin to make our own sprouting mix, kick-starting our seedlings that will be planted in just a few short months.

All of our tricks and techniques that we use at the Garden can be adapted to use at home, so if you are interested in trying something for yourself, come and chat, hang out and learn something new!