Water is crucial for your plant to stay upright, metabolize, and to stay cool. Without enough water, pressure inside the stems drops, and the leaves will wilt. Water helps in transpiration, and in cooling the plant. Your plant knows how to adjust a little to its conditions, but remember that there is no single watering schedule throughout the year. In high summer, when the light is strongest, your plant will require more water; in winter, your plant will go dormant and require less. A good rule of thumb is to never let your bonsai get too dry. Feel the weight of the pot in your hands after a good watering. The pot should drain quickly, but it will still be heavy. Pick it up the next day -- when it starts to get light again, it is time to water. The pot should never feel too light. This means the soil inside is very dry, and your plant will not survive long in these conditions. On average, a medium sized pot will stay humid for several days indoors. If outside, it will need daily watering.
“I’m on vacation and can’t find a plant-sitter!”
In summer we all need to take a break, but your bonsai will thank you if you give it a good soak before leaving. If you are away for more than a week, you can place your bonsai in a shallow dish with about 1/2” of water. This will humidify the air and allow water to come up through the bottom of the pot. It should be fine like this for up to 10 days, but take it out once you are back and resume your normal watering routine.
Sunlight allows your plant to create the food it needs to put out new growth and store energy for winter. Each plant has their own requirements. Full sunlight means 3-6 hours/day of direct or very bright conditions. Partial sunlight means at least 3 hours of direct sun, and partial shade is anything from 1-3 hours. Southern facing windows, barring any close buildings or trees, will usually receive the most daily energy from the sun. East and west facing windows receive morning and evening sun, respectively. Morning sun is great for many of our partial shade plants, being more gentle on delicate leaves. If indoors, place your plants close enough to the window to receive plenty of light, usually within 5 feet. Larger windows of course will cast greater light further into the room. It is fine to move your plant around your home as necessary. If you want to place it in a windowless bathroom to keep you company, that’s fine, but remember not to leave it there for days. All of our plants like to be outside, too. If you don’t have a balcony or outdoor space, crack open the window to give them fresh air. Take them on a field trip!
Good air circulation is important for cell growth. A slight breeze will stimulate the leaves and branches, encouraging roots to become stronger. It also helps to prevent the growth of molds by evaporating any pooling water quicker, and prevents dust buildup on the leaves.
Most of our bonsai are outdoor bonsai, meaning they go dormant in the colder months of winter. Displaying your bonsai indoors is fine, 2 weeks or less, but they will need outdoor conditions to remain healthy. Opening the door or window and placing the bonsai on the windowsill will help, if you have no outdoor space.
In winter, keeping your bonsai indoors in a warm room during January and February is like staying awake for days -- you just want to rest. Our bonsai can tolerate freezing temperatures and can stay outdoors or in a cold room during the winter. Find a protected area that stays between 25° and 45° F. Protect the plant from strong winter winds by placing the pot in a box, planter, or other container without a lid. If inside a cold room like a storage room, placing your bonsai in a box gives it extra protection from getting damaged or knocked over. Your plant should not need much water or light, as it won’t be growing, but you should check up on it anyway. When the pot is very dry, give it a full soak of water. This protects the roots, helps the plant put out new growth in spring, and prevents the leaves (on conifers) from drying out. Check the plant in early spring for any new growth, and when the nightly temperatures are above 32°F, bring it back into the open. Only start bringing the bonsai into your warmer living space when there isn’t wide fluctuations in temperature between indoors and out.