Oil Lanterns That Heat a Greenhouse

Greenhouse Temperature

• If your greenhouse is located in a cold climate you may need to supplement the heat in the greenhouse to keep your plants toasty warm. Sunlight will warm the greenhouse during the day, however an uninsulated greenhouse will cool quickly once the sun goes down. Greenhouses temperatures should be maintained above 37 degrees Fahrenheit. If the temperature is allowed to fall below 37 degrees. Tomatoes and other delicate plants will be damaged.

  A passive solar greenhouse does not depend on an artificial heat source but rather uses water, concrete, stone or other heat collecting material to collect and hold heat. Many greenhouse owners further insulate their greenhouse with a 6- to 10-inch layer of wood chips. However, a sudden drop in temperature may cause concern. To offset possible plant damage, savvy greenhouse owners have traditionally used oil lanterns as an effective heat source. "Country-side," published by British Empire Naturalist's Association, reports that oil lanterns were used as early as 1907 to provide greenhouse heat.

  Today, although there are more efficient ways to heat a greenhouse, including heated underground piping, oil or gas heaters and electric greenhouse heaters, many greenhouse owners rely on oil lanterns to provide greenhouse heat during power outages.

Fuel For Oil Lamps

• Lamp oil, vegetable oil or kerosene may be used in the majority of oil lanterns. Never mix the type of oil you use in an oil lantern. If you wish to change the type of oil in your lantern, the lantern must be cleaned and the wick replaced. Kerosene is the cheapest oil to use in the greenhouse, however it emits an unpleasant odor. Smokeless and odorless kerosene, also known as British paraffin, is available for purchase online or from local home and garden supply stores.

Lantern Size

• Hurricane lanterns with a metal fuel tank and handle are often used as an extra source of heat in the greenhouse. Oil lanterns are available with various sizes of wicks and fuel tanks. Many oil lamps have a wick that is 1/2 inch wide. Three-quarter-inch wicks are also available. The size and height of the wick controls the size of the flame. Lanterns can be hung or positioned on their flat base. The Jupiter Cold Blast oil lamp by Dietz is an effective way to heat a small greenhouse when cold winter weather threatens to damage your plants. Oil lanterns are available with a 84-ounce fuel tank that will burn for up to 72 hours without refilling.

  Ceramic or brass wick holders are available to turn any bottle into an oil lamp. Tapers are available in sizes from 1/2 to 1 inch. A 5/8-inch taper fits a standard wine bottle. Ceramic or brass tapers are inexpensive. Keep a few on hand for when the temperature in your greenhouse drops, and you will have a readily available source of temporary heat.

Oil Lanterns Versus Oil Heaters

• Although heating your greenhouse with oil lanterns is effective way to keep frost out of an otherwise unheated greenhouse, oil heaters are easier to maintain and service if heat is needed for more than just occasional use.