Tropical Bonsai Tasks in April:
With the coming of warm spring weather, we should be thinking about moving our indoor plants outside.
Indoor plants will benefit greatly from spending the summer out of doors. After spending the winter in our often too hot and dry homes, these plants will rejuvenate in an environment close to their native habitat. However, they should not be moved out until your are sure that the temperature, both day and night, will not drop below 50 degrees. When locating these plants out of doors, the transition should again be gradual as when we take plants out of winter storage. Place them out of winds and do not subject them to strong sunlight all at once. Try a north or east exposure where they will get morning sun and not the bright afternoon sun, for the first few weeks. Gradually move them into full sun and afternoon partial shade. Once they are acclimated to the outdoors, you may repot those that need to be. I usually repot tropical bonsai in late May. You should have switched to your summer feeding program when you observed new growth. Your trees should also be included into your regular watering schedule. Be on the look out for insects and diseases. Do not begin trimming and styling until late May or early June.
More on that next Month. A popular plant for both outside and indoors is Boxwood Buxus sp. Boxes are densely branched shrubs native to Europe and Asia. Most boxes are grown as hardy bonsai and are so down to zone 6. However, more and more boxwoods are being grown as bonsai indoors. It is evergreen and makes an excellent all year bonsai. Box is popular because of its tiny leaves and flowers and it’s tolerance for extensive pruning. Boxwood can be kept very small because of this and is a great species for mame bonsai. It does equally well in sun or shade and its indoor light requirement is only 800 lux. Although somewhat hardy, they should be protected from frost and cold winds. I have boxwood growing in my gardens and doing very nicely. As all plants grown indoors, they enjoy spending summers outside in the fresh air. Watering should be moderate, but it does not like wet soil. Freely draining soil is a must. Allow them to dry somewhat between waterings. Box dislikes acid soil and adding an occasional dose of lime to the soil is recommended. Feed with a bonsai fertilizer weekly during summer and monthly during winter if you are growing them indoors. One application of organic fertilizer should be given during active growth. Growth on boxwood can be very slow. Box can be wired at anytime and is tolerant of radical treatments. Most are styled by the clip and growth method. Control shape by thinning and pinching of unwanted new growth. Box should be repotted every two years with spring being the best time. As boxwood is a broadleaf evergreen, there is more leeway with appropriate times than with deciduous species. Avoid potting in very hot weather. Boxwoods are very disease resistant but are sometimes bothered by mites, leaf miners, blackfly, greenfly and red spider mites.
Buxus harlandii (harland box) is perhaps the best variety for indoors.
Buxus microphylla (Japanese box) has leaves under 1” and is hardy in zones 5-8.
Buxus microphylla ‘compacta’ (dwarf boxwood)
Kingsville and Morris Midget are recommended.
Buxus microphylla ‘koreana’ (Korean boxwood) is the most hardy and is grown in zones 4-8.
Buxus sempervirens (common or English boxwood) This is a very long lived plant and grows in zones 6-8. Boxwoods from colonial days are still alive in Virginia.
Although junipers seem to be the choice for beginners in the bonsai hobby, I would whole heartily recommend that you take a look at the boxwood. It is as tolerant of abuse in care and management as junipers and gives you a leaf and flowers instead of needles. It can be grown either indoors or out. And, if you’re into miniatures, this is the tree for you.
