Potted trees provide many benefits to the home gardener. Easy location changes mean optimal growing conditions for the tree throughout the year. Containers filled with sterile soil eliminate most disease and insect problems. Potted trees also add aesthetic appeal in small areas. Despite their many benefits, potted trees need special care during the winter. Containers provide poor root protection in freezing temperatures. They also tip easily in the wind, potentially damaging branches. Finally, potted trees may not be hardy in a given environment, requiring a different growing location when temperatures drop.
Avoid fertilizing from mid-summer on. This provides adequate time for your potted tree to harden off, preparing for winter weather. Continued fertilization encourages new growth and keeps the plant using all its energy stores too late in the season.
Place containers in protected areas outside, away from cold northern winds. The south side of the house or other structure provides the best protection in most landscapes. Alternatively, put them in a greenhouse or wrap the pots in insulating material, such as blankets, during the freezing weather. Remove such coverings daily to avoid tree damage from reduced sunlight. Ensure proper pot size, aiming for pots that are equally tall and wide to provide optimal root protection from winter temperatures.
Take potted trees indoors during the winter if they are not hardy to your area. This may include plants such as citrus trees, a popular choice for potted trees. Acclimate trees slowly to indoor lighting conditions by gradually reducing the amount of daily light exposure over a period of two to three weeks before bringing them inside. Skip this process if you bring the potted tree in for only a day or two during freezing temperatures.
Locate indoor potted trees away from drafts and vents during the winter. Keep them near windows with good lighting and consider adding additional lighting in the room to maximize plant health. For potted trees that remain outdoors over the winter, reduce watering because trees need less water in cooler weather.