Kate graduated from Sonoma State University with a Bachelor of Science (BS) degree in biology. She currently resides in Sonoma, California.
What Is Bonsai?
Bonsai is a special Japanese art form that is used to create dwarfed trees that resemble real trees but are small enough to keep in houseplant-sized pots. These trees have been used for centuries as part of the décor in many traditional Japanese homes. In recent years, bonsai trees have gained mainstream notoriety as aesthetic accents in modern homes.
If you are a first-time bonsai owner, you will definitely want to brush up on the specific care requirements for these unique plants. In this article, we'll go over basic guidelines and care instructions for growing and maintaining your bonsai tree.
Quick Bonsai Care Summary
- Lighting: Five to six hours of direct sunlight per day are recommended. This requirement can change based on the variety of bonsai and if the light received is direct or indirect.
- Watering: Water when the top 1–1.5 inches of soil are dry. Water enough to soak to the bottom of the pot. Never allow the soil to dry out completely.
- Soil Conditions: Use a conifer blend or other bonsai-specific potting soil.
- Repotting: Repot every one to five years depending on the bonsai. Pale yellow leaves indicate that it's time to repot.
- Fertilizing: Use a fertilizer specifically formulated for bonsai trees. Fertilize year-round for an indoor tree.
- Pruning and Trimming: Regular light pruning is recommended.
The above information is for general reference purposes. Each of these aspects of care will be discussed in more detail below along with more specific recommendations.
Bonsais need approximately five to six hours of direct sunlight each day. If your tree is in a location where sunlight is not very intense, you can increase the number of hours (up to 16 daily) that your tree receives sunlight to compensate. If you move your tree from an area with low light to an area with more intense, direct light, do so gradually to avoid damage to your tree. Avoid artificial (incandescent) lighting, as this will not provide the full spectrum of light needed for your bonsai to develop properly.
Since environmental factors change continuously based on the season and time of the day, regularly changing the location of your tree may be the most appropriate approach in terms of balancing lighting, humidity, and temperature depending on your situation.
One of the most challenging aspects of the care and maintenance of bonsai trees is establishing when and how you should water them. It’s important to note that water requirements generally depend on several factors.
Factors That Influence Watering Requirements
- Number of hours of sunlight exposure
- Specific bonsai variety
- Soil conditions
- Tree size
Since there isn’t a general formula for watering frequency, you should always monitor the condition of the topsoil. If the top 1–1.5 inches of topsoil feel dry, it is probably time to water your plant. This can be done once every day or once every few days depending on the above-mentioned factors. Over time, you will come to understand what your bonsai requires.
General Bonsai-Watering Guidelines
- Regularly monitor the dampness of the plant's soil by pressing your finger into the dirt, taking care not to damage any roots.
- It’s recommended to water the plant during the morning hours.
- During the summer or warmer days, your bonsai will require more water.
- Water no more than once a week during the winter—too much water isn’t good during the dormant season.
- If sunlight exposure decreases, watering requirements will also decrease. If sunlight exposure increases, watering requirements will also increase.
- Water the tree at regular intervals during the growing season so your bonsai can adapt to the watering schedule.
It is very important to choose bonsai-specific soil for your tree. Consider a soil mixture such as a conifer blend that has the correct texture as well as a uniform distribution of ingredients.
Good potting soil is one that encourages maximum aeration and water drainage. It will allow standing water in the soil to drain out while still retaining some moisture for the plant. Remember to use soil that has an appropriate pH value, preferably in the 6.5 to 7.5 range.
In order to provide an environment that triggers the tree’s growth and development, it is necessary to repot your plant regularly. The most ideal time to transfer your bonsai to another pot is immediately after winter. This is because they store a lot of energy in their roots during the dormant season and can use it for growth as soon as summer begins.
Generally, repotting is necessary every one to five years. Faster-growing and younger trees will need repotting more often (about once a year), whereas older trees will require it less often (closer to every five years).
Signs That You Should Repot Your Bonsai
- The plant’s leaves begin to turn pale-yellow and young ones emerge.
- Bud formation on the stem is observed. If this occurs, prune the plant’s roots prior to repotting.
These decorative plants are normally grown in small pots and therefore rely more heavily on fertilizer than many other house plants. Generally, potassium, nitrogen, and phosphorous fertilizers are good for bonsai plants, as these are responsible for the green color of the leaves, root development, and flowering. It’s advisable to buy a bonsai-specific fertilizer from a reputable distributor.
Bonsai Fertilizing Tips
- For outdoor trees, fertilize during growing periods.
- Indoor trees require regular application of fertilizer throughout the year.
- Regulate nitrogen usage during summer and dormant seasons.
Pruning and Trimming
While some people prefer to call experienced gardeners for the pruning, shaping, and wiring of their bonsai trees, these are things you can easily do yourself. Even though maintenance pruning can be done at any time of the year, structural pruning is best done when the plant begins to grow after the dormant period. Remember to use sharp pruning tools in order to avoid inflicting damage to your tree.
In order to get the best shape for your plant, only cut off branches and shoots that seem to have extended beyond the desired canopy. For better results, structural pruning should always be followed by accurate wiring.
This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.
Questions & Answers
Question: Can a Japanese Holly Tree be grown indoors?
Answer: A Japanese Holly Tree is a popular type of bonsai that is often sold as an indoor plant. Yes, it is possible to be successful growing a Japanese Holly indoors, although these plants very much prefer to be grown outdoors.
Although they do seem to do surprisingly well in low light conditions, they have a strong need to be outside and experience the seasonal changes. Specifically, the Japanese Holly needs to experience the cold of winter to really flourish during the remainder of the year.
So yes, it is possible to grow a Japanese Holly Tree indoors, although it is fairly difficult. If you do attempt this, consider placing the plant outdoors during the winter so it gets that exposure it needs. This plant is fairly hardy and will handle cold winters well, although severe frost can still cause damage so it should be taken indoors if frost is expected.
Joey on July 07, 2020:
I live in central New Mexico. What temperature range is ideal for bonsai juniper? Thanks!
Chyiann on February 28, 2020:
Thanks my tree was so sad
Jon-Paul on January 25, 2019:
I've just watched "The Karate Kid" where Mr Miyagi prunes his miniatures and I thought 'I could take pride in something like that so I'm gonna follow you're tits and see how my first "little tree" turns out!
Some are worth thousands too..... Crazy. Thanks for the info Kate.
I'll let you know how I get on.
Ashlee on May 12, 2018:
I’m not really sure how to take care of this bonsai tree I just bought
Kate Daily (author) from California on December 19, 2017:
Thanks Linda! They can be tricky at times. If he ever wants to try again, you should make sure he knows that keeping it alive really is possible! Lots of good information out there now a days.
Gail Kowal on December 11, 2017:
I appreciate the work that went into this article. I love Bonsai Trees and have been thinking about buying one. I sense there is much more to learn on the topic. Thank You.
Kate Daily (author) from California on December 06, 2017:
Thank you Linda!
Linda Crampton from British Columbia, Canada on December 03, 2017:
I think Bonsai trees are fascinating. I gave one to my father as a gift once, but he wasn't able to keep it alive for long. I think this article would have been very helpful for him.