Watering
Even though your bonsai is dormant and will not be actively growing, it still needs a small amount of water in winter. One way to water your bonsai in the winter is by placing it in an unheated garage or basement. You can also place snow on top of your bonsai in the winter, which will eventually melt and provide water for your tree. It is not necessary to fertilize your bonsai during the winter since the tree is not actively growing.
While you can provide water at any time, the best way to water your bonsai is to allow the roots to breathe. Overwatering your bonsai can cause the root system to become disrupted, preventing the proper absorption of water and nutrients. This can lead to rotting roots and other problems. You can move your bonsai into a new pot if it begins to show symptoms of overwatering. If you have trouble repotting your bonsai in the winter, you can give it ample sunlight.
After the winter, you can start watering your bonsai again. You can also spray the foliage with a spray to prevent the growth of diseases and insects. You can find various sprays at your local garden center for this purpose. It is a good idea to use one of these sprays if you are worried about disease or insects attacking your bonsai.
Winter care for your bonsai tree will depend on whether your climate is warm or cold. Deciduous trees will shed their leaves in the winter, but will regrow them in the spring. Conifers, on the other hand, need their winter rest too. While they do not require indoor storage, they need protection from sub-zero temperatures and drying winds.
Light
Winter is a tough time for bonsai trees, but these plants have adapted to survive cold temperatures over the years. Evergreens and deciduous trees will cease photosynthesis once the temperatures drop below freezing. Trees from tropical and subtropical climates will suffer less damage from winter weather, but they must be protected from harsh winds and extreme cold temperatures. The proper preparation for winter begins during the warmer months, when the tree’s leaves develop. To ensure that the tree is healthy and resistant to winter, it is important to feed the tree during this time.
It is possible to overwinter your bonsai trees outside, as long as the area is protected from strong winds. If you live in an area with a lot of snow, you can place snow on your tree to help it stay moist. It’s also essential to repot your bonsai tree in the spring. During winter, you can also start learning more about your bonsai tree, so take classes and join a bonsai club.
Another way to protect your bonsai from winter weather is to place a cover over it. A sheet of clear polyethylene, for example, is waterproof and will protect your bonsai from the elements. If you live in a climate with very cold winters, you can even use hay bales to protect your bonsai.
When you’re storing your bonsai during the winter, be sure to disinfect the storage area thoroughly. A good way to disinfect the area is to apply Jeyes fluid. This is an old nursery practice that has proven effective.
Temperatures
Temperatures for bonsai trees during winter should be kept below freezing to prevent damage to the tree. The low temperatures can damage the trees by bursting their cell walls and creating air pockets, preventing sap from flowing properly in springtime. These changes can cause tissue loss, ranging from tertiary twigs to entire branches. Some trees have adaptations to survive these cold temperatures, but there are others that do not.
Different bonsai species have different levels of cold hardiness, and it’s best to check with your local nursery for the USDA Plant Hardiness Zone of your chosen tree. Although this is a good starting point, you’ll need to be cautious because the temperatures that affect bonsai roots may fall below freezing during the coldest months.
A variety of maples are suitable for cold-climate bonsai. The Amur Maple is a popular choice and can tolerate temperatures as low as -49 degrees Fahrenheit. These trees will also grow quickly during warmer months. Another popular choice is the Field or Hedge Maple. Chinese Elm and Siberian Elm are two other good choices for cold-climate bonsai.
Although many tropical bonsai are hardy and can survive freezing temperatures, they still need some special care during the winter months. They should be protected and hydrated well to ensure that they continue to grow healthy. Even if temperatures are below freezing, bonsai plants still need plenty of sunlight to grow properly. A grow light is a great way to make sure that your tree receives the necessary light.
Sheltering
To protect your bonsai trees from extreme temperature changes in winter, you can use a cold frame or greenhouse. This will minimize the fluctuations in temperature, protect them from big drops in temperature at night, and keep them from drying out in strong winds. You can also cover the pots with styrofoam, which will help keep the roots protected. You can also place your trees in the ground, but ensure that the ground is relatively dry, as it can cause the roots to dry out.
Before overwintering your bonsai tree, make sure that you provide it with sufficient water. Winter winds can dry out the foliage of evergreen trees and evaporate water from their leaves. The soil may also freeze, preventing water from moving up to the leaves. As a result, the leaves become desiccated and eventually die. These effects can be exacerbated by bright sunlight. To avoid this problem, water your bonsai trees regularly, before storing them in a warm, sunny place.
If you do not have a greenhouse or outdoor greenhouse, you can bring your bonsai indoors when winter begins to become severe. When temperatures are mild, bring them back outdoors to their sheltered spots. During the colder months, you should be aware of late frosts and keep the branches warm. Also, if you have a greenhouse, you can open the doors to keep the winter air from damaging your bonsai.
Some bonsai trees can tolerate low light indoors for a few months during the winter. Others will go dormant and slow their growth. One of the best species to grow in low light is the Hawaiin umbrella tree.