Dawn Redwood Bonsai Care Guide
Perhaps one of the most fascinating of bonsai specimens, up until the 1940s Metasequoia glyptostroboides was only known by its millions-year-old fossils. The majestic tree was presumed extinct until a rogue cluster was discovered in China and eventually seeds shipped all over the world, resulting in a renewed surge of Dawn Redwood population, bringing back to life a beautiful species that the world had thought died with the dinosaurs.
These deciduous conifers grow upwards of 100 feet tall and 25 feet wide in their natural habitat. The species makes a striking bonsai, not only because of its beautiful taper but because it is literally a living relic of the dinosaur age, sure to become a favorite conversation piece.
The trunks of this tree are straight and tapered with grooved, reddish bark. They boast unique, feathery, lacy-needled foliage that turns from light green to yellow to bronze before falling. Its branches are formed into a graceful upsweeping pattern.
Although the Redwood enjoys humid heat, it is hardy in most North American zones. It will need to be brought into the garage or house during frost, allowing it to go dormant without letting the roots freeze. This bonsai can be an indoor or outdoor specimen, as long as it gets plenty of sunlight. Outdoors a "dappled sun" effect is best, which can be achieved with a lattice or screen.
Metasequoia is not drought-tolerant and particularly in hotter climates will need attention to moisture. The soil should be well-drained but not permitted to dry out. The species is hardy but the foliage is rather fragile and if the leaves are allowed to yellow and dry the tree may die. In order to ensure that the soil is moist enough you can dig an inch or two into the pot with a finger.
Feed with a half-strength balanced fertilizer every three weeks throughout the spring and summer. No fertilizing is necessary in the fall and dormant season.
This bonsai is typically trained in the upright formal style, due to its straight trunk and evenly growing foliage. This majestic, historic tree looks especially stunning as part of a clump, forest, or slanting arrangement.
Aggressive trimming of foliage, particularly at the top, is necessary in order to maintain the tree's triangular shape. The foliage grows profusely as do the branches, so regular pruning is needed to keep the larger ones from becoming too big for the tree. Regrowth is vigorous and dense, so don't worry that you will ruin your tree by trimming frequently.
Wiring should be done during the dormant period. Perform the bends gently and leave wires in place for about 3-6 months. They should be monitored regularly to avoid cutting into the bark.
Chinese Elm's can be propagated by seed or cuttings. To grow from seed, be sure to collect the cones from a tree that is at least 20-30 years old. They can be gathered when they fall off the tree and kept in the refrigerator. Once they start to open, shake the cones in a large coffee can, in order to free the seeds. Stir the seeds into an organic soil mixture and spread into a shallow bonsai container, covering with about ¼" of fine gravel (this keeps the soil surface dry and discourages fungus as the plant is establishing). Place the pot in sunlight for two weeks and wait for sprouts to grow. The seedlings will need to be protected from frost.
For cuttings, allow the tree to grow over the course of the year, then in early spring trim to your liking and put the cuttings into water to soak for a couple days. Pick the best cuttings and plant them in a community box with rooting hormone. In mid-June transplant the surviving cuttings into single containers, allow to grow for a season then transplant to small pots the following spring. As your fledgling plants grow, continue trimming so that a good shape is achieved from the start.
This should be done about every other year, depending upon root growth. The roots of the Elm grow quickly and should be trimmed down to a fist-sized ball. This species does not have naturally occurring surface root spread (nebari), so to rectify this you can wire a piece of slate under the roots and spread them out gently by hand before placing in a new pot.
Insects/Pests & Diseases:
Particularly if kept as an outdoor bonsai the Metasequoia will naturally develop defenses to pests and disease through the normal temperature and environment changes that encourage its hardiness. If you do notice insects, the plant can be sprayed with a gentle dish soap and water mixture. It's always better to begin pest control with non-chemical methods.