Q: Can I grow a mango tree in North Saanich, BC? I have a greenhouse.
Yes, it is possible to grow a mango tree in your greenhouse in North Saanich, but they do not do well in cold weather.
Kyle Exner of B.C. Greenhouse Builders Ltd. recommends keeping the greenhouse above 4°C (40°F) for active growth, as mango trees will go dormant around 4°C. Be careful to not let them go anywhere near freezing because this will damage them. If your greenhouse is cool, Exner advises taking extra measures to keep the mango tree warmer than the rest of the greenhouse. His advice for the best way to do this, because it can be tricky to keep the entire tree warm in a greenhouse with different zones of temperature, is to have two maximum-minimum thermometers in the greenhouse. One placed near the mango tree and the other near the centre of the greenhouse. Keep the heater close to the mango tree and monitor the temperature closely at the start of winter as well as during cold spells.
Exner also says it is okay to wrap the tree in a towel or blanket during cold spells to prevent damage. If it is preferable to move the tree into the house in the winter, Exner expects that would work if it is maneuverable and if light and humidity are accessible.
To produce fruit all year, Exner suggests keeping the greenhouse at a minimum 10°C (50°F) overnight with warmer daytime temperatures and a supplemental source of light in the late fall, winter and spring. Usual greenhouse growing methods are also important, such as good air circulation, and cooling and shading in the summer.