Zelkova Bonsai

The Japanese Zelkova, also known as Zelkova Serrata or Zelkova Schneideriana, is a type of bonsai tree that is native to the Eastern China, Japan, Korea and Taiwan.

How to Identify

The Zelkova tree is a beautiful, medium-sized species that can grow up to 100 feet tall outdoors. It is characterized by multiple limbs and stems sprouting out of a short, round trunk. These sprouting stems create a round, almost dome-shaped top.

The flowers bloom in the spring and can be identified by its egg-shaped buds with many overlapping petals. The flowers are a yellow-green color and can be found growing in groups along newly sprouted stems. The leaves are distinguished by their oval, serrated edges. The leaves are smooth on the underside, however, on top they are rough to the touch.

The twigs and branches are slender and the bark can be a gray-white or gray-brown color.

Growing a Zelkova Bonsai Tree Indoors

Although the species can grow up to 100 feet outdoors, these trees can adapt to be an indoor plant. When choosing to grow your bonsai inside, look for location in your home that includes the following:

  • Sunny Windows
  • Well Lit
  • Cool Position (Do not let the bonsai “bake” in the sun)
  • Higher Humidity Levels (You can accidently dry out your bonsai)

Watering Your Indoor Zelkova Bonsai

Your indoor tree compost should never dry out – the soil should be kept evenly moist at all times. Be sure to monitor your plant’s moisture levels and do not make watering an unnecessary routine. Over watering the tree can result in root rot, drooping leaves and even plant death.

Indoor Feeding

During the winter months, your Zelkova bonsai tree will only need to feed once a month. During the spring and summer it is a good idea to schedule balanced feeding sessions every week. Zelkova trees do not need to be fed when out of leaf.


For the first 10 years of the tree’s life, you will need to repot once a year – usually in the Spring when the buds have full extended. After the first 10 years, the Zelkova Bonsai will only need to be repotted when necessary.

Growing the Zelkova Serrata Outdoors

The tree is a great species for outdoor cultivation. The acclimatized plant is actually very frost resilient. It is important to remember, however, that temperatures below 5 degrees Celsius can result in damages to the branches, roots and overall health of the plant.

Watering Your Outdoor Zelkova Bonsai

Outdoor watering periods for the species are very similar as to the indoor watering periods. It is important to keep compost moist and avoid letting the tree dry out. Because you have chosen to grow your tree outdoors, be sure to pay attention to high temperatures, sun exposure and strong growth. You may need to water your tree more often during these conditions.

Feeding (Outdoor)

Outdoor feeding of Z. Serrata is a little different than indoor feeding. It is important to feed your tree high Nitrogen on a weekly basis for the first month after the buds open in the Spring. After that, use standard feed every two weeks until late summer.

Repotting the Outdoor Zelkova

Outdoor Z. Bonsais can be winterized during the winter months and repotted in basic soil mix after Fall.

Caring for the Soil

When choosing a soil for your indoor or outdoor bonsai Zelkova, look for something with a sandy, soil potting mix. It is important to enhance this basic soil weekly in the Summer and Spring with a balanced liquid fertilizer. Fertilizer will only need to be applied once a month in the Winter. Once the leaves have dropped, do not fertilize or try to enhance the soil.

How to Shape Your Tree

The most common shape Zelkova bonsai tree owners want to achieve is a dome or “broom” shape. Follow these steps in achieve a broom shape:

  • Ensure trunk is straight
  • Allow trunk to grow to desired thickness (personal preference)
  • Remove tap root
  • Cut the trunk above branch diversion point
  • Allow branches below diversion point to grow
  • Prune branches back until there are only a few internodes remaining
  • Allow branches to grow out again

By following the simple pruning steps listed above, a broom or dome shape should be achieved. It may take a few rounds of pruning to get the full broom shape you are looking for.

Avoid These Common Mistakes

The Japanese Zelkova Bonsai is a beautiful tree and should be cared for by a bonsai enthusiast who has time and patience on their side. Avoid these commonly bonsai mistakes when taking care of your plant:

  • Do Not Under-Water It. As previously mentioned in this article, it is very important to keep compost and soil moist at all times. Lack of water can kill your tree quickly. When going out of town, be sure to entrust a friend or family member with the responsibility of caring for your bonsai plant.
  • Do Not Keep Your Tree in the Dark. An indoor Zelkova should be kept on a windowsill or in a room that receives a lot of natural sunlight. Your outdoor Zelkova Bonsai should be planted in an area that received plenty of sunlight. Keep in might other trees and plants nearby – your plant may end up competing for sunlight with other trees in the future.
  • Do Not Over Water the Zelkova Serrata. As under-watering can be detrimental to the tree’s health, over-watering can be just as harmful. Soggy roots can lead to root rot and death of your indoor or outdoor tree.
  • Do Not Over-Shape. Shaping your Zelkova Bonsai is harmless to the tree, however, you should only make major changes to the shape once a year. Regular pruning and trimming is fine throughout the year as long as it’s not overdone.