Basic Bonsai Care

For Southeastern Pennsylvania

From early spring to early winter, you must be sure to water your Bonsai. It is a good idea to water it every day from spring to summer. Rain is a blessing when you own Bonsai! It means you can take the day off! You should never let the soil dry completely out. There are two ways you can water your Bonsai.

The first is for you to soak the entire pot in a shallow dish of water for about 20 – 30 minutes. The water should not rise above the soil level of the pot because this can wash away the soil. This way of watering your Bonsai is also good when you don’t have a lot of time. You can put it in the water and go. You should not leave it in the dish of water for more than a day, and don’t do this all the time.

The second way to water your tree is to shower it with a fine spray from a distance for about 15 minutes. You must be sure your tree is soaked through. If you just get the top of the soil in the pot wet, the delicate roots at the bottom will suffer! The reason you water it from a distance is so that you don’t wash the soil away with the force of the water.

Your tree is properly watered when the soil has darkened, the plant is heavier and water is dripping out of the holes in the bottom of the pot.

If your Bonsai is a specimen that naturally goes through dormancy every year then you must leave your tree outside! It will die if you try to bring it indoors in winter, and it will not be as healthy in summer as if you were to leave it outdoors.

Choose a location that gets several hours of sunlight per day (preferably morning sun). Too much sun could injure your tree because of the delicate nature of it. Also try to protect it from high winds by placing it near other foliage, next to a wall, etc. (High winds could knock over your Bonsai and will also dry it out very quickly. On windy summer days you may need to water more than once per day).

Your tree must be "winterized". There are several ways to do this.

Tropical trees (ficus, palms, and bougainvillea for example) can be brought indoors and kept in a sunny window. Be aware that dry winter heat affects your plants and they should be kept on a humidity tray or misted in addition to carefully monitoring the watering.

Deciduous and evergreen trees do best if you can prevent the pot from freezing but typically trees can handle down to 15° F. There are many different opinions on the best way to winterize your outdoor trees. I group them all together and cover the pots in mulch or leaves, leaving some of the branches exposed to the sunlight (you could even wrap a small towel or blanket around your tree if you only have one or two. Another way to winterize is to bring your trees in to an unheated garage or basement. The temperature should not go above 40° F as this may bring the tree out of dormancy before it is ready. Some people actually bury the pots of the trees in the ground leaving the trunk and branches exposed.

You can begin to bring your trees out of winter storage in March, and put them into storage around early December.

If your tree has wire on the branches, gently remove in about a month. The branch should hold the shape it was given when wired. To learn more about wiring there are many good books and web sites, which I will list at the end of this document.

Bonsai are kept small by constant pruning. You must prune back the leaves and branches several times over the growing season (spring to fall) and you must trim the roots once a year or every other year. As with wiring, pruning can be quite involved and to get good at the aesthetic part of bonsai, you should read more on this subject.

Basically, you can trim back most of the new growth on your tree, leaving branches and leaves that you like and removing ones you don’t. If you remove a branch, the energy that was directed by the plant to that branch will be redirected to the remaining branches, thereby increasing the strength and life of the remaining branches.

"Bonsai – Illustrated Guide to an Ancient Art" (Sunset Books)

"The Bonsai Workshop" by Herb L. Gustafson

Anything by John Naka!