Bonsai Oasis

Caring for Your Bonsai In All Seasons

There are many circumstances and dilemmas concerning bonsai growth and care that must be taken into account as the seasons change. There are certain specific things that any bonsai grower must do to insure the bonsai will survive the seasons, mainly because the bonsai itself is not in the ground. If the bonsai was grown from a forest tree, it has to live outdoors, except for short periods when the grower may bring them inside to view them or show them off.

These should only last a short time, meaning only two or three hours, and good ventilation is required if one is to bring them in during the summer time. Cool nights, sunny days, and daily mist or rain are required for bonsai in the summer time. Unfortunately, not all climates offer these conditions, so the bonsai grower must supply them by his or herself. Extremes in light, rain, wind, and temperature should be avoided. Daily watering is necessary, but overwatering can be very harmful; be careful that they don’t become waterlogged.

For the best drainage conditions, place the bonsai on a slatted sand in your garden. Three to five hours of direct sunlight are required daily, but an area that is shaded in the afternoon is recommended. Bonsai growers should use the autumn to prepare their plants for winter. The growth of the plants needs to be slowed; less frequent watering as well as discontinuation of fertilizer application will cause this to happen. Pruning or cutting any branches is discouraged after Mid-August. Bonsai plants can easily die in winter due to low temperatures and dry winds. A protective greenhouse, cold frame, or pit may be required if the temperature ever drops below 28° Fahrenheit. Cold frames are very useful for bonsai plants; they are small boxes that will protect the plant during winter.

However, even while they are in the cold frame, they still need to be watered while inside. It doesn’t need to be done quite as often, though, perhaps only every other day. Over watering is actually the leading cause of bonsai death, not desiccation. After winter is over and spring arrives, new bonsai can be started, old ones can be pruned, and training measures can be continued. The plants will continue to adjust to these practices during the remaining part of the growing season. Temperatures above 15¬∞ Fahrenheit are usually allowable for bonsai plants. Anything below this requires some form of protection. It seems obvious to simply bring them inside; however, this could be harmful to the plant. Depending on the temperature and circumstance, however, this may be necessary.

It is important to remember that a period of cold dormancy is required for any woody plants. The plants may die if they do not go through this important period.

Temperate climate plant species have evolved to go through this dormancy period in order to survive the winter. The plant’s biological clock tells it to slow down its activity and prepare itself for the freezing temperatures of winter. There is no reason to force a plant to change its dormancy cycle. During cold temperatures, placing a plastic film or a tarp over the plant is helpful. This is best done during the night, and during the day it should be removed.

It is also sometimes recommended to put the bonsai in the ground during the winter, since the ground will not get nearly as cold as the air.

The best way to do this, experts say, is to keep the root balls in the pots and bury them in the ground up to the rim of the pot; then, the pots can be covered with mulch, usually dead leaves. However, you can forego the leaves if there is consistently a large amount of snowfall in your area during the winter. The advantage of wintering bonsai in the ground is that they will go through their cycle naturally in time with outside conditions. Other wintering methods such as unheated garages, sheds, cold frames, window wells, or cold rooms often do not achieve this result.

These other methods are obviously much more convenient as they don’t involve digging or mulching; however, they do tend to warm up much more quickly when spring arrives, and the tree’s natural cycle will be interrupted: growth will resume before temperature and outside conditions are truly ideal.

The root balls, regardless of the method used, ought to be very well moistened before the tree is put away, and checked on a regular basis, perhaps weekly, to insure that they will not dry out. In the event that they do dry out, the tree must be watered. It is also recommended that the tree faces either north or east in whichever wintering spot is chosen, and that the spot is in the shade for the majority of the time. When the trees begin to grow, however, they will not be able to withstand the warmer temperature of spring. Frost resistance is increased during the fall, but frost resistance is decreased during the spring.

While the closed, swollen buds will still be able to withstand short, mild frosts, when the leaves unfold and the buds open, they must be returned to frost-free shelters so that the frost will not cause any serious damage. Full-size deciduous trees always lose their leaves in the winter. Bonsai are simply miniaturized versions of the full-sized deciduous trees, and so it will also lose its leaves. Again, this is completely normal. Just as with full-sized trees, they will grow back in spring.