What Are the Dangers of Growing Cactus With Non-Vented Propane Heaters?

Emissions

• Non-vented propane heaters differ from outdoor or patio heaters in that they do not emit carbon monoxide. Despite this, the National Fire Protection Association recommends that you install a carbon monoxide detector near a non-vented propane heater. The detector will help you determine if there is a harmful carbon monoxide leak in your heater. Although carbon monoxide is not harmful to plants, it is fatal to humans who garden in the enclosed confines of a greenhouse.

Tipping

• Propane and other fuel heaters pose a fire hazard if they are tipped over. Tipped propane heaters can spill flammable fuel throughout your greenhouse. If this fuel is ignited, it can spread quickly and cause a fire that can destroy your greenhouse and all of the cacti inside of the structure. To prevent this, you should only use a propane heater that has an automatic shutoff valve that will turn the machine off if it is tipped over. You should also avoid placing your propane heater in the walkways of your greenhouse.

Electroshock

• Although some cacti grow in an arid environment such as the desert, others grow in the treetops of a tropical rain forest. These cacti may not do well in a dry environment. The presence of a heater in the greenhouse will draw the moisture out of the air and will require you to re-humidify the air with mist or a humidifier. Additionally, tropical succulents may require more water than their desert counterparts. When providing humidity or water, you must take care not to cause an electrical hazard by allowing water to form puddles or mist too close to the heater. An electrically-powered propane heater will present an electroshock hazard if it is allowed to sit in water.

Burns

• The walls of a propane heater, as well as the air directly around the heater, may become incredibly hot. Although you need to keep the heater out of walkways, you should also keep it about 3 feet away from walls and plants. If a plant or the wall of your greenhouse is allowed too close to the heater, it could cause a fire hazard. Greenhouse walls made of plastic can melt if they come into contact with the walls of the heater and cacti may catch on fire.