Juniper Bonsai

Dr.Bonsai

Hello Jack,

Thank you for your question regarding your juniper

JUNIPER HEALTH:
If the tips of the juniper are lush and green, the tree is healthy. If the tips wither, yellow or brown, it is a sign that something is not right. Usually this is either over/underwatering or lack of adequate light.

As a juniper grows, the tips should remain green. However, you may notice that further along the branch (moving closer to the base of the tree) the scales will brown as part of the natural process in which the branch matures, needles are shed and bark develops.

GROWING TREES INDOORS
Juniper can adapt to indoor culture, but proper watering may be difficult to learn. Poke your fingertip into the soil about 1/2 inch and see whether the root ball is still damp. Some growers keep a small piece of chopstick stuck in the soil and can withdraw that and check the moisture condition of the soil. The roots need air as well as moisture, so it's important not to keep them drenched for excessive periods or they may suffocate and rot.

LIGHTING
Most home and office lighting is not designed to maintain photosynthesis. Your tree will be dependent on available natural light. A "gro-light" may be of some use, but it will need to be placed VERY close to the plant to be of any benefit, because light intensity falls off with the square of the distance. This means that a light placed at 6" will have the power of 4 equivalent lights placed 12" away.

R&R
When the weather becomes favorable after the frosts subside, your tree will enjoy a vacation outdoors where it can benefit from natural light and ventilation.

CHECK THE SOIL!
Some imported trees have a variety of gravel, rocks or figurines actually glued together on the surface to hold the product together in shipment, and that glue can obstruct the soil-air interchange and suffocate the roots. Moss, too, should not cover more than 1/2 of the surface of the soil or it can become a problem.

If it is established in its container you can even ease the tree (soil, roots and all) out of the pot and check the condition of the roots (check for an objectionable odor indicating that rot may be present).

FERTILIZATION
Fertilizing a juniper is easy. For plants that appreciate a slightly acid soil (like pine, juniper, azalea and many flowering and fruiting shrubs and trees) you may use Miracid, a type of Miracle-Gro with a lower pH, available at your garden center.

Mix the fertilizer at approximately 1/2 the strength suggested for plants and apply during the growing seasons at 2-week intervals. You may either apply it by immersion or overhead watering.

It should be pointed out that underfertilization is rarely the cause of problems with trees.