You don’t have to be a gardening veteran to start growing bonsai, and you can even start with one of the numerous species that thrive indoors!
While many people tend to think bonsai gardening is for the tried-and-true plant experts, it’s not always the case. Instead, you just need to jump in and get growing!
There is no substitute for experience, so what are you waiting for? Get to growing your indoor bonsai tree already!
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Can Bonsai Trees Grow Indoors?
Yes! However, most bonsai trees are to be kept outside, where they are exposed to all four seasons. Despite their miniature size, bonsai trees are a lot like normal trees. They require similar conditions to thrive in nature or your home, so certain considerations must be made.
Only tropical and subtropical species are suited to the indoors, where they receive consistently high temperatures and regulated living conditions throughout the year.
How to Take Care of a Bonsai Tree Indoors
Caring for a bonsai tree is a bit more of an intensive task compared to caring for ordinary trees, especially when you’re dealing with tropical species.
Bonsai trees grow in small pots that possess restricted storage and a limited amount of nutrients, requiring you to pay closer attention to how they react to watering, feeding, temperature changes, and their container or pot.
Additionally, a tropical bonsai tree needs an indoor environment that optimally replicates a natural outdoor setting from where the bonsai is — direct sunlight, stable humidity levels, and high temperatures are all common factors that play into growing great bonsai trees.
You can consider this section as the Potted Exotics version of “Bonsai Care for Dummies.” It contains all the fundamentals for proper care of almost all bonsai species.
Do Bonsai Trees Need Direct Sunlight?
Bonsai trees require 5-6 hours of regular direct sunlight. Direct sunlight is extremely important in early spring and summer during the growing season. If full sun is not provided to most bonsai tree species, they will wilt, their foliage will weaken, and yellowish leaves will appear.
Can Bonsai Trees Grow in Shade?
There are numerous species of trees that prefer shade in nature. Bonsai trees from such shade-loving species will naturally prefer shade. However, indoor shade provides significantly less light exposure compared to outdoor shade. So, you should consider using artificial lighting for your indoor bonsai plants.
During the winter months, bonsai trees grow more slowly or go dormant.
Throughout the cold winter, you must ensure adequate indoor lighting for your indoor bonsai tree in order to maintain growth. This goes for low light tropical bonsai species, such as the Hawaiian Umbrella tree, too.
Is Too Much Sun Bad for Bonsai?
Not watering your bonsai regularly and abruptly putting it in direct sunlight may cause overheating and burning. You should immediately move your precious bonsai away from the scorching sun if you see yellowing leaves or wilting during full sun exposure.
Remember: Bonsai deserve a complete care package, and 5-6 hours of regular direct sunlight is enough light for almost any bonsai.
Can I Grow Indoor Bonsai with Grow Light?
Most deciduous trees and evergreen species do not need additional lighting during their dormancy period since they completely shed their leaves. But, tropical and subtropical species require further luminescent care when placed indoors, especially in winter when natural light is scarce.
If your bonsai receives too little light, it will quickly start to dwindle. Pests and insects will see this as a golden opportunity to swarm your precious plant and make matters worse.
The solution is simple; get yourself an artificial lighting setup consisting of fluorescent lights.
Since tropical and subtropical bonsai species require 12-15 hours of illumination per day, you can switch your fluorescent lighting system on for a few hours during the morning and after sunset, allowing the bonsai to receive plenty of light.
How Should I Water My Bonsai?
This depends on the bonsai species, but for indoor conditions, most will do fine with one watering per week! During the primary growing season, you may need to water every 3-4 days, but be sure not to water until the soil is dry 2 inches under the soil.
How Often Should I Water My Bonsai?
In a nutshell, never water your bonsai by a set routine! If the topsoil appears dry, go ahead and water it. However, never water when the soil is wet. This will eliminate the dangers of root rot from excess water in the root system.
To check for soil moisture levels, the best hack is to place your finger about two inches (one centimeter) deep into the soil. Or, you can equip yourself with a moisture meter and take your bonsai care game to the next level.
The best thing to do is carefully examine each bonsai; see how each reacts to watering, their water retention, and the time it takes for the topsoil to dry. Once you know their preferred pattern, watering your bonsai will never be a problem.
Can I Water My Bonsai with Tap Water?
The answer to this question depends on your tap water source. However, I generally don’t recommend using tap water, as it can contain chemicals like fluoride, which can be harmful to some plants. If possible, rainwater is the best option!
What is the Ideal Temperature for My Bonsai?
Similar to their full-grown counterparts, bonsai trees also require moderate temperatures that prevail in a natural environment. These temperatures range from 70°F to 85°F (20°C to 30°C).
Bonsai root systems are immensely sensitive to high temperatures. During the winter, you will have to ensure the root system doesn’t dry up.
A tropical bonsai prefers relatively warm temperatures, so it should be kept indoors where moderate temperatures persist year-round; they can also be treated as outdoor bonsai trees but should be brought indoors during the winter.
Ironically, tropical bonsai species are more susceptible to critically high temperatures compared to other types of bonsai trees.
Cold temperatures can also damage the roots, so you should shift your trees indoors during the winter. A typical indoor environment should be sufficient, as room temperature is ideal for both tropical and temperate species, given substantial natural light is received.
What is the Best Humidity for Bonsai?
Contrary to your home’s environment, which generally has low humidity due to heating or air conditioning, a bonsai needs relatively high humidity to thrive in an indoor environment.
The good news is that keeping humidity levels in check is almost effortless. All you need to do is place your bonsai on a humidity tray carrying water, mist the foliage a few times a day, and open a nearby window to let fresh air in.
Should I Mist My Bonsai Every Day?
You’ll get a mixed bag of answers to this question, but typically, I don’t recommend misting any plants other than air plants. This is because the only real benefit of misting is to clean the foliage or boost the ambient humidity, but the boost is extremely short-lived. When misting, you also run the risk of water settling on the leaves, which can attract pests, introduce disease, or lead to fungal growth.
Ideal Soil Types
What is the Best Bonsai Soil Mix?
The best indoor bonsai soil mixture consists of akadama, pumice, and lava rock in a ½, ¼, and ¼ ratio, respectively.
Further, the best indoor tree soils have the following qualities:
- Optimal Water Retention: Between waterings, the soil must retain enough water to provide the necessary moisture to the root system.
- Excellent Drainage: Excess water needs to quickly escape from the small container. Otherwise, your bonsai may suffer from a lack of oxygen or more complex problems like root rot! The last thing you would want to happen to your long-term bonsai companion.
- Proper Aeration: Aeration allows efficient exchange of gasses between the roots and bacteria. Tiny gaps between irregularly sized soil particles make it all happen.
What is the Best Fertilizer for Bonsai?
The general rule of thumb is to use a fertilizer with a high nitrogen content and an NPK ratio of 10:6:6 during the growing season (typically, this means the spring season).
A balanced fertilizing schedule should be adopted during the summer with an NPK ratio of 6:6:6.
During autumn, use a moderate fertilizer that goes easy on the nitrogen levels – think something along the lines of 3:6:6.
Where is the Best Place to Put an Indoor Bonsai Tree?
The best location for your indoor bonsai tree is right in front of a west or south-facing window to provide the most sunlight possible throughout the day. Even the slightest increase in distance from the window will result in a critical drop in light intensity.
Not sure what type of light you have in your home? Check out our article covering the basics of understanding the lighting conditions in your home!
Where is the Best Outdoor Placement for My Bonsai?
To truly cherish as much new growth as possible during the growing season (early spring to summer), place your bonsai in the brightest and sunniest place in your yard. You must account for the right temperature changes when deciding the outdoor location, but the most important thing is direct sunlight!
If your area is notorious for heat and ridiculously high temperatures, you will have to partially cover your bonsai with shade during midday. In this case, you can place it underneath a tree or next to a fence to provide lower temperatures.
Why is My Indoor Bonsai Tree Dying?
For many indoor bonsai growers, the first sign of color change on leaves or the first presence of pests will immediately cause panic! The good news is that if you can recognize the signs of severe problems before they get out of hand, you can begin treatment for the best chance of recovery.
The following symptoms could indicate a serious problem like pests or root rot, or they could just mean you need to make some small changes in your care regimen.
- Yellow Leaves
- Brown Leaves
- Wilting Leaves
- Visible Soil Insects or Ants
- Smelly Soil
Yellowing of leaves can occur due to overwatering, which causes root rot. During the heat of summer, underwatering also persists for bonsai trees. The fierce sunlight during the summer is also notorious for turning leaves yellow.
Browning of leaves is caused by overwatering, underwatering, and a lack of sunlight. Brown spots also accumulate on leaves after pests and spider mites attack.
Wilting of leaves is due to a lack of proper watering, sunlight, and unstable temperature changes.
Leaves are often lost because of repotting, stress, irregular watering patterns, and a lack of sunlight.
Root rot is fatal for a tree, and it is hard to cure as well. To prevent this menace, you will have to take extra care of your soil mix, ensuring it does not have improper water retention and a lack of aeration.