There are several ways to go about gardening outside during the winter if you are just a lil handy.
In the very cold climates you can increase the heat output by soaking grass clippings that you saved throughout the year, as well as using compost. Ive even seen some people run ducting from their dryer vents to help out a lil during the day. If you go all out and run a gasifier in a greenhouse to power lights and heat for deep winter growing you can supplement the heat like this lady did (though she uses no additional heat source).
Cynthia's Rabbit Warmed Greenhouse
Cynthia's greenhouse is located in North Central Idaho, in a mountainous
region that is probably a USDA class 3b or 4a for hardiness. Normally, the
last frost occurs in early to mid June while the first frost usually occurs
in early September. This is a region with a very short growing season.
Summer temperatures rarely exceed 80˚. Winter temperatures typically
reach -10 to -30˚ F in January.
In spite of this, using this greenhouse, Cynthia is able to grow fresh
produce most of the year. There is no heating in the greenhouse other than
the rabbits and the composting activity that goes on under the rabbit
cages. Using this greenhouse, she is able to begin planting things like
tomatoes, etc. in February or March. The greenhouse is located to provide
full exposure to the sun from the southeast and south. To the west, there
is a hill and trees which shade the evening sun somewhat.
With this greenhouse, it is possible to get 9-10 months of production on
about 500 square feet of growing space. Normally, in this area, the
growing season will only last 2-3 months. As an example, when visited in
December, she was still growing kale in the beds.
Cynthia's greenhouse is constructed as follows:
Overall dimensions: 14 ft. wide by 40 ft. long. Peak roof with wall
height of 8 ft. Roughly a 5-12 pitch on roof.
Construction materials: Rough cut 2x lumber for framing. East, South and
West walls and roof are formed using corrugated plastic sheeting. The
North wall is solid.
Rabbit hutches: total of 16 hutches. Two rows of eight each in the center
of the greenhouse. Hutches are 2 ft. by 4 ft. by 18-24 inches high.
Hutches are elevated approx. 2 ft off the ground and have screen bottoms,
allowing the droppings to fall through to the ground beneath. Droppings
from the rabbits are allowed to compost under the hutches. She then adds
this composted material to the grow beds in the greenhouse.
Grow beds: there are several grow beds in the greenhouse. One long wall
faces south. On this wall, there are three sets of grow beds, each roughly
18-24 inches wide, that run the length of the wall. One of these grow beds
rests on the ground. The second is elevated approx. 3 ft. above the first,
with the third elevated approx. 3 ft. above that one.
Another large grow bed is located approx. 2 ft. above the rabbit hutches.
It is 4 ft. wide by approx. 32 ft. long.
A fourth bed is located along the north wall, elevated about 6 ft. off the
ground. Like the ones on the south wall, it is approx. 18-24 inches wide
and 40 ft. long. There is a shelf below this grow bed for tools and
general work and storage space below that.
The framing for the roof extends over the center grow bed and provides
supports for climbing plants (such as beans, tomatoes, melons, etc.).
Fluorescent light fixtures are located over each grow bed and could be
potentially used for grow lights, although this is not done by Cynthia.
Ventilation: the only ventilation in the building are two man-doors in the
ends. She is able to keep the heat down in the summer simply by opening
these doors.
Composting: Cynthia allows the rabbit droppings to compost under the
cages. Media from the grow beds was originally sawdust, some sand, and the
composted rabbit droppings. She originally ordered in 1 lb. of red wiggler
worms to assist in the composting. She uses the composted material (and
worms) for all her grow beds. Very little additional fertilizer is used at
this point.
