Bonsai Maintenance Instructions

The best comparison to illustrate why some plants live in different settings, climates or conditions is to compare tropical plants to all other plants.

Tropical plants generally thrive between 60 and 90 degrees.

There are plants that live in sub zero weather and those who live in 100+ weather.

Temperature is one of the factors that tell us which plants live inside or outside. Water, sunlight and humidity requirements also tell us if they will live indoors or outdoors.

There are some who believe and state that there is only one true species of bonsai trees who will live indoors. 

The reason this is wrong is that there is no plant or tree which lives in a climate or environment which no other trees will live in.

All tropical plants from around the world live in “tropical weather”. Temperatures, sunshine, water and humidity are virtually identical in all tropical climates.

Tropical plants need protection from too much heat, cold and not enough humidity. So in non-tropical climates they live indoors more easily than outdoors and still require a bit of extra care.

Some tropical zones reach 100 degrees with 100 % humidity and the plants do just fine.

However, 100 degrees with low humidity kills plenty of topicals or indoor plants all around the world.

General living conditions for tropical plants are the same general needs of plants that will live indoors.  (there are some

 exceptions within each category.)

The five general needs to keep a plant or bonsai indoors are these:

 temperature, sun, water, humidity and food.

1-Temperatures in most homes hoover around 70 degrees which is perfect for Tropicals or indoor plants. Tropical plants generally thrive between 60 and 90 degrees.

In my nursery I turn on the heater for my tropical bonsais at 45 degrees. They don’t die nor do they thrive. When it warms up, they start blooming and growing beautiful new growth.

2-Sun requirements are impossible to give an answer to “how many minutes of sun are required each day?”. However some general guidelines help tremendously. If your tropical bonsai is in a room with no windows or no light it will die. If the room is dark and dingy, it will die slowly. LOTS OF LIGHT is the proper setting with one limitation. Do not let the sun beat on the leaves when outdoor temperatures are over 68ish degrees. Due to global warming, and a diminishing ozone layer, our tropical plants’ leaves

are burning at around 68 degrees. For over 40 years I’ve instructed people to not let direct sun touch their tropical plant leaves when outdoor temperatures are over 70 degrees.

3-Water tropical plants and tropical bonsais like it’s raining. Water the leaves, stems and trunk every time you water. If you live at the coast or moderate climates where temperatures do not get over 80 degrees water every 2 or 3 days. If you are in Sacramento, Modesto or Arizona weather you should water lightly every day and create humidity for your tree.

4-Humidity:  If you are in Sacramento, Modesto or Arizona weather you should place a spray bottle near the tree and spray it 2,4,6,8 times each day. You may create a humidity tray by placing small decorative stones in a one or two inch deep tray, platter or dish. Place the bonsai on the stones and keep the tray filled with water. As the water evaporates it humidifies the tree a bit. I highly recommend placing the tree on the counter of your shower room when you shower. Tropical plants live and thrive in very high humidity.

5-Fertilizing your tropicals is important. Most tropical bonsais that bloom need acid fertilizer (a measurement of potential hydrogen). Simply buy “acid” food with phosphorus. Phosphorus is for blooming plants. The indoor or tropical bonsais I make that require acid loving food are the Fukian T trees. The ficus take a general purpose indoor plant food generally.

Some junipers do well inside or outside due to their extremely durable nature.

When planted in the ground they withstand below zero and above 100 degrees. They live fine with no water for the entire year, they survive under snow and sub freezing weather in the mountains.

Indoor Juniper Bonsai Care: No humidity is required for a juniper because its’ natural habitat is dry arid weather. When watering a juniper bonsai, when living inside, you do not water until the surface of soil is dry to touch or dry looking. Remember that the complete soil ball below the surface is always damp or wet or the roots will continuously die little by little. When the soil surface is dry take the tree to a sink and flood it until you can count 10, 20, 50 drops pouring out the bottom holes. This ensures that the soil is drenched thoroughly. This also flushes the soil of many of the impurities we have in our water: salts, bleaches and harsh minerals. This process takes the soil 4 or 5 days to dry out enough to water again in weather like San Jose, Napa, Oklahoma… At the coast it may take 4-6 days to dry out enough to water. In dryer, more arid climates it may take 1 day, 2 days or 3 days to dry enough to water again.

Sun requirements for your indoor juniper bonsai are as follows. As much light as possible is great for the tree. However, due to the fact that a bonsai is in a shallow pot with a relatively small amount of soil it heats up much more quickly than if it were planted  in the ground. This means that you do NOT allow the sun to beat on your juniper bonsai when outside temperatures are above 80 degrees. If your bonsai is in a room with poor lighting it will die !!!

Feeding your juniper bonsai is important. I prefer using a liquid fertilizer that you place a few drops in water, then water the soil. Most brands carry a liquid indoor general plant food. Follow the directions well. If you use a very low % of nitrogen like fish emulsion (around 1-2% nitrgen) you may feed it every month. If you use something a bit stronger like 10% nitrogen then 3, 4 or 5 times a year is adequate. Anything stronger than 10% I don’t recommend.

Outdoors there are basically plants that do well in sun, others in shade and others who do well in partial sun and shade. All junipers do well outdoors in sun. I try not to let the sun beat directly on the juniper when temperatures are over 80 degrees due to the fact they are in a small pot. In the ground they handle over 100 degrees. Many other varieties of bonsai take this same sun condition: manzanita, pines, redwoods, pomegranate, citrus, roses, cottoneaster, chinese weeping elms (These are varieties I produce.) Bonsai which grow primarily in shade are all tropicals, azaleas, rododendron, camellia, japanese maple, trident maple. (These are varieties I produce.)

When watering these outdoor types of bonsai trees water thoroughly every other day when below 70 degrees. Water every day when 70 or above. When over 80 degrees I recommend watering every day and keep all of them in the shade due to being in small pots which heat up and dry out quickly.

There are so many varying conditions which affect the life and health of trees and bonsai: wind, soil drainage, elevation, sun, type and freqency of fertilizing,  These suggested guidelines come from over 40 years experience and a degree in ornamental horticulture in 1975. So, my recommendations are sound, proven and consistent. However, there are factors which can change from region to region, climate to climate.

If you have questions for the care of your bonsai trees please feel free to text me at 707-342-3897

Bonsai of Napa Valley