Juniper Bonsai for beginners

This is a good primer on Juniper Bonsai from bonsaisite forums

Why Can't I Keep My Juniper Bonsai Inside?

Many bonsai vendors tell beginners that Junipers can be kept inside year-round. Unfortunately, this just isn't true. Keeping your Juniper inside permanently will result in your bonsai developing a sickly appearance over time and dying. If your juniper’s needles have turned yellow and are falling off, it probably died weeks ago.

Junipers need a dormant period (a state of growth where the plant rests and grows very little, if at all). Juniperus communis, or the Common Juniper, grow as far north as Greenland, Newfoundland, and northwest Alaska. In the Northern Hemisphere, the farthest south a Juniper can survive is Houston, Northern Florida, or in the mountains of Mexico. They are not a tropical or sub-tropical plant and should not be treated as such.

Some people who live in areas that receive heavy snowfall during winter, where temperatures frequently drop below freezing, might be advised to keep a Juniper indoors to protect it over this short period. To do this, you must simulate its natural environment. If you have an unheated room, it can be closed off from the rest of the house and the window left open. A garage can also be used. Remember to keep your Juniper away from any heat vents of any kind. Exposure to heat during a juniper’s normal winter will prevent the plant from going into dormancy.

If you are keeping your bonsai outside (probably the best option) and are afraid of it getting harmed by the winter weather, there are several things you can do to protect it:

1) place it in a flower bed and bury it until just the pot is covered with soil (this will insulate it from the cold)

2) place it in a sheltered area, i.e. under a low-hanging tree, or anywhere else where it will be protected from the weather such as a shade house.

3) make a frame for it and cover the frame with shade cloth so heat won't build up inside it and place mulch around the bottom edge. Generally if you live in a warmer climate (like USDA zone 6-7), you shouldn’t have to worry about winter protection.

If you keep you Juniper in a garage or closed off room, you should be careful how you introduce it back outside. Place the Juniper in a location that doesn't get much sun and out of the wind. Over a period of a few weeks slowly move the Juniper back to a more open location.

Why Did My Bonsai Die?

Your bonsai may have died as a result of negligence from yourself, or negligence before you bought it. The majority of bonsai sold in malls or by small-time bonsai vendors are sold only as a novelty and are only grown to look good at point of sale. These are commonly known as ‘mallsai’.

When you purchase a bonsai, make sure to get it from a genuine bonsai dealer, or at least someone how knows what they are talking about. They will be able to tell you how to properly care for your bonsai and can help you pick out a plant that is suitable for your location. They will also know what species of plant your bonsai is, which is the first thing we want to know when you are asking a question about your bonsai on the forums!

The worst places where you could buy a bonsai are malls, department stores or anywhere else where the people selling the bonsai know little or nothing about their care. These are normally mass-produced bonsai that have been shipped over from one climate to another. Placing the bonsai in a warm environment at this time can disturb its dormant period and send it into shock.

The manufacturers of these ‘mallsai’ may have placed tags that read "indoor bonsai" on the Junipers even though they are outdoor bonsai. They may place them in a pot that doesn’t have a drainage hole, plant them in the wrong type of soil, and place a layer of gravel on the surface and glue it down to stop the soil from falling out of the pot during shipping. The layer of glue and rocks prevent the water from getting to the soil and can kill the plant if not removed after purchase.

Juniper care

There are some basic requirements that need to be adhered to so that your bonsai can survive and grow well.

1) Your bonsai needs to be in good soil. Proper bonsai soil does not contain any peat material at all. This is because peat retains too much water. It also hardens if dried out and once this happens is very difficult to get wet all the way through again. The best soil to use is a loose, free draining soil. You need one part fine pine bark to one part small gravel (such as small aquarium gravel) for this. Otherwise, try to buy a bag of ‘bonsai mix’ from your local nursery.

2) Feeding your bonsai is important. Fertilize your Juniper with a weak slow-release fertilizer of 10-10-10.

3) Non-tropical bonsai should be primarily kept outdoors and need a period of rest each year during wintertime known as dormancy. The easiest way to ensure your Juniper receives a dormant period is to keep it outside.

4) Water your Juniper regularly, but make sure you do not over-water. How often you water depends on where you are, how hot it is, and what season. Watering could happen every day or it could happen every three days. If you are not sure on when to water your juniper, feel the soil by poking your finger in it. If it feels dry or nearly dry, you should water.

5) Lighting is important: Keep your Juniper bonsai in either full sun or partial shade.

6) Repotting your Juniper depends on how old it is and how long it has been in training. For a young bonsai – less than six years old, you ideally should repot every year. Repotting involves changing the soil (although keep it in the same type of soil) and trimming the roots. This encourages growth. If the bonsai is older, you should repot it every 3-4 years.