The ancient giants of elms are plants that are hard to imagine in miniature form. But thanks to complex multi-year formation and careful care, these trees can be found today among indoor plants as well. The art of bonsai creates true living works of art out of elms. It is not easy to grow them in living rooms, but with diligent care elms will become the pride of any collector.
small-leaved elm - indoor mini version of an ancient Chinese legend
In nature these giants, impressive both in beauty and size, are admired for their mere appearance. Even in garden form, elms are luxuriant woody only for very large plots. Not surprisingly, elms that can be grown at home always seem like a small wonder, a plant truly exclusive. "Tame" the ancient beauties helps the art of bonsai, while preserving the key features of these trees - a beautiful silhouette and unusual foliage.
Spread only one species - small-leaf elm (Ulmus parvifolia). The genus belongs to the Elm family of the same name. In indoor culture, small-leaved elm is also known as Chinese elm, elm caragash, birch bark. It is an endemic of Southeast Asia, most widespread in China.
Wall elms appear to be ancient and very old trees in miniature. It is perhaps difficult to find another plant that shows such a pronounced aged effect as the elm. It is the fine-leaved elm that allows beginners to succeed and masters of bonsai to show their skills and create the most fantastic silhouettes and curvatures. The height of such small-leaved elms is limited to 15-80 cm, which with their "initial" size of up to 25 m looks like a fantastic miniature.
The main feature of elms that made them irreplaceable plants for bonsai is their uniquely thick branching and small leaves, which allows forming mini-copies as close to natural plants as possible in decorativeness. The gray, smooth, beigeish-brown bark with red young twigs emphasizes the complex structure of the tree. With age, the bark not only cracks but also peels. Scars remain in place of severe wire tightening, sometimes created on purpose for greater naturalness.
The leaves of the small-leaved elm are indeed very small: in room culture, they rarely grow more than 2 cm. The impeccable ovoid or oval shape, solid edge, dark but not pale green coloration and bright luster emphasize the beauty of elm greens. The leaves on the shoots do not sit densely and the twigs are perfectly visible underneath, which allows you to fully appreciate the beauty of the silhouettes and lines. Almost always elms shed their leaves for winter which considerably reduces their decorativeness, but the dormant period of elms lasts only till February when new shoots start to develop actively. And in room temperature elm can keep its leaves till the growth of new shoots, then it quickly and rapidly renews itself (in fact, in warm wintering the plant behaves almost like an evergreen).
The period of elm flowering in room culture is determined by its "habits" and temperature regimes. Usually elm blooms in late summer or fall. But if the wintering temperature is inadequate, you can not wait for flowering, observing it in a different timing from the traditional. Small-leaved elms bloom very beautifully. Tiny, graceful flowers, which you want to look through a magnifying glass, seem precious in combination with small leaves. And when after flowering gradually mature much broader fruits, the plant is at its decorative peak.
Home care for fine elm
Fine elms are not the most difficult bonsai species. It is believed that this plant puts up well even with improper care, but such a statement is not quite true. For elm you need to guarantee not too hot conditions, and consistently bright lighting, and constant access to fresh air. The plant does not like overwatering. But it is not easy to choose a comfortable mode of watering, and often elm prepares unpleasant surprises, then dropping leaves, then surprising with its sluggish appearance. Therefore it is better to have this bonsai for flower growers with experience, for those who can assess the problems and take corrective measures in time.
The most difficult thing in growing elms is the right choice of plants. Most bonsai trees derived from the small-leaved elm are outdoor plants, wintering in the cool and decorating terraces and gardens. These elms, native to the Japanese mountains and northern regions of China, are the ones with bronze young and autumn leaves that fall at the end of the garden season. Only elms native to southern Japan, southern China and Taiwan are considered indoor elms, which are more heat-loving, dropping or partially dropping their leaves only in the cold of winter, not showing off their spectacular autumn coloration. By specifying the origin, you will eliminate the risk of buying a less room-adapted outdoor bonsai.
Lighting for small-leaved elm
The level of light directly affects the ornamental quality of elms. And it should be kept stable throughout the year without exceptions. Elms are light-loving plants, but it is better to protect glossy leaves from direct sunlight. To maintain the usual mode in winter, plants should be moved to lighter places and windows, or additionally extra light. Elm does not like full artificial extra light, but extra light is good for the plant while keeping the leaves.
Fine elms are perfectly adapted to more sparse light only in nature, in bonsai form they are super-sensitive to insufficient light.
Small-leaf elms tolerate temperature variations well, which in principle is not the case for most of their competitors used to produce bonsai. But this adaptability and resilience has its downside. Elms don't really like the heat and do better in cooler rooms, even in the summer. In heat, the leaves of the plant become unpleasantly sticky, the plant as if it attracts dust to itself, and can even drop its leaves. Keeping it below 5 degrees Celsius the room elm in bonsai form will not withstand, but otherwise any temperature up to 22 degrees Celsius is fine for it. In winter it's desirable to lower the temperature by a few degrees, but elm can put up with the usual temperatures as well.
It's considered that the shedding of leaves depends directly on the wintering temperature, in warm rooms the leaves can be kept until the crown renewal in spring, but in fact this factor is rather conditional: the shedding or keeping of leaves is also affected by the origin, growing area of original mother plants, and the features of temperature regimes at the early stages of bonsai formation. When buying it it's always better to clarify this parameter, as well as the minimum temperature that a bonsai elm can withstand (elms from northern China, outdoor and even bonsai can withstand frosts down to -5, unlike room elms).
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The most difficult thing in selecting conditions for fine elm is sensitivity to stagnant air. Not only is it better to move elm throughout the warm season (when the temperature is above 8-10 degrees at night) to fresh air, on a balcony or even in the garden, but also to put it in a place where the plant will have an opportunity to enjoy frequent airing.
Watering and air humidity
E elm needs very careful watering. The plant does not tolerate overwatering, overwatering, stagnant water in the pallet, but it likes quite high humidity of the substrate. When watering, water in small portions, checking how moist the substrate. Between these procedures for elms need to dry the soil almost halfway. In winter, watering is reduced, the humidity of the soil should be low, not average, the soil should remain dry all the time, regardless of the air temperature.
To the humidity of the room elms are undemanding. Only if the plant is in heat, it is better to provide a strong increase in humidity.
Feeding for bonsai elm
Unlike many of its competitors, popular as bonsai, elm likes fertile soils and is quite demanding of feedings. The plant is not fed with special bonsai fertilizers, but with ordinary universal fertilizers for houseplants, alternating them with organic fertilizers if possible.
Fertilizing is carried out throughout the year, even in winter. For elm the classical frequency of these procedures - once every 2-3 weeks - is suitable. During the dormancy period, the frequency of nutrition is reduced to once a month. Reducing or stopping feeding in August or September allows for brighter, not yellow, but bronze colors of the fall leaves, but resort to this trick only for future cool overwintering.
In room culture, elm needs not just pruning as desired, but regular shaping and restraint. The plant withstands radical pruning, especially if there have been lapses in regular treatments and the plant has become too elongated or dilated and has lost its beautiful silhouette. Elms are pruned from spring to fall, guided by the growth rate of the plant itself, but such regulation is acceptable only for young shoots. Old and thick twigs are only trimmed in late fall or during the winter. For elm, each shoot is allowed to grow no more than 4 internodes, then it is shortened to the first or second leaf.
Silhouette, direction of growth, curvature of branches and trunk are controlled by stretching and wrapping with wire. On elms, wrapping and restraint is not traumatic, so it is carried out at its discretion during active growth. Wire or stretching can be used during dormancy, from November until March.
Transplanting and Substrate
Elms, even when very young, are not transplanted annually, but every two years. Mature plants are transplanted as infrequently as possible, waiting for signs of lack of free soil.
Fine elm in bonsai form can only be transplanted in spring.For this plant, as with fertilizer, it is not necessary to look for a special bonsai substrate. Elms are grown in a universal substrate - light, loose, nutritious and of good quality.
Root pruning is mandatory when transplanting for any Chinese elm. Elm's roots are very thick and tangled. They are pruned, restraining their size, growth, and giving them a nice shape.
Diseases and pests of fine-leaf elm
Pests of fine-leaf elm are considered atypical for indoor culture. The greatest danger to bonsai are sting beetles and graphiasis, which are almost impossible to control in houseplants. Almost always infestations occur before purchase. It is much easier to cope with red root mites, rust, caterpillars, which are treated with standard insecticides and fungicides. © Etsy Studio
Propagation of fine-leaved elm
Wall elms are propagated only by cuttings. Regular pruning allows you to get rooting material all the time. Elm cuttings are traditionally treated with growth stimulants, planted in a nutritious moistened substrate at an angle, and rooted in warmth under a hood. Rooting is not a quick process, but the young plants develop very actively. Formation begins after the elm forms the third pair of leaves. Cuttings are deposited in individual containers with control of the size of the root system immediately after rooting.