Week 51 in Your Vegetable Garden

 Thinking About A Greenhouse?

Sitting in front of a fire in the fireplace while the snow rages outside is one of life’s special luxuries.  But for me, another special experience in the depth of winter is to be repotting some geraniums in a greenhouse or conservatory while the snow piles up outside.  Whether you have a greenhouse, a sunspace, or a conservatory, the winter is when that space gives much joy while easing the stress of the day.

If you do not have such a space, but are thinking about getting one of these structures, you need to take your planning very seriously.  It is not an easy decision from any perspective.  You need to be clear about how you wish to use the space.  In most cases, we are talking about investing a substantial amount of money so you want to be right the first time.

The first question is whether this sunny space is primarily to grow plants or is it a space for people to enjoy.  The space for plants is usually called a greenhouse.  You can spill water or potting soil on the floor and not worry about it.  A greenhouse can be allowed to get as cool as 55 degrees at night.


Nancy's Conservatory


A space primarily for people is called a sunspace or conservatory.  You can still grow plants in these spaces, but the design must address the comfort of people so temperatures do not go much below 68 degrees at night.

A greenhouse that is easy to manage and somewhat economical to heat is attached to the house is some manner, thereby sharing some of the heat from the house.  I used to have a lean-to greenhouse made from old wooden storm windows attached  to the house with the cellar door inside.  I built another greenhouse that sat on the second story over the family room and was heated by the wood stove in the family room.  I used those greenhouses to overwinter plants from outside like geraniums, impatiens, and rosemary.  I grew lettuce  and swiss chard for winter salads, and grew orchids under the benches.  In the spring, I started all my seedlings in the greenhouse.  It was closed down for the summer months.

A sun space is designed first for the comfort of people. It can’t get too hot or too chilly.  A modest sun space will cost from $5000 to $15,000.  The English conservatory is catching on in this country.  It is simply a fancy sun space which will cost from $20,000 on up.

Nancy’s 8 x 13 foot conservatory by Canterbury is used to hold her collection of tropical plants over the winter.  As you might expect, there is no space left for people in this room.  Throughout the winter however, we have fuchsia, impatiens,  bougainvillea, and crown of thorns in continual bloom; talk about a pleasant place to watch the snow fall.  Clipping fresh rosemary for spaghetti sauce all winter is another benny.

At night and when the sun is not shining in the winter, the south facing space is heated with a thermostatically controlled electric heater.   When the sun is shining, vents are opened to release the excess heat.  Having a greenhouse or a conservatory does take daily attention to keep the plants from cooking or freezing.

I have a friend with a modest conservatory that has in its center a sunken hot tub.  In one corner is a small table where he and his wife have morning coffee all winter.  Three sides of the space are filled with all manner of flowering and foliage type tropical plants.  He has rigged a system of fans with a thermostat so in the winter when the heat from the sun reaches 80 degrees, the fans move that heat into the house.  In the summer they move the heat outside and pull some cool air from the house into the conservatory.  Sitting in the hot tub, surrounded by a jungle of beautiful plants while the snow is blowing outside must be a special treat for sure.


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