I've been doing a little research on juniper bonsai this afternoon - as that is the species of my bonsai. The Bonsai Site offers the following insight:
Overview: Junipers (Juniperus) are hardy, non-flowering, evergreen conifers with now many new developed varieties that are easy to grow, prune and train. They are a rewarding family with responsive, fairly rapid growth.
Junipers generally have long, trailing branches and are able to be trained into many fantastic bonsai styles - all except broom. The branches usually respond well to wiring and reshaping, however the stiffness of some cultivars make it hard to shape the plant into anything but its natural form.
Other Comments: Most varieties of juniper are hardy and can remain outside the house - even during relatively harsh winters. (The tree can be brought inside during the winter, but generally you should not let the temperature exceed 15 degrees Celcius.) Protect the rootball from frost as well as recently trained or wired trees.
General Care: Pinch out the tips of new buds any time during the growth period.
Only conduct major pruning during the spring or autumn/fall, but not in summer. Maintenance pruning can be done throughout the season. Regularly pinch off the young shoots.
Fertilise (sic) in early spring.
One caution: Wear gloves when working with junipers, for the prick of the needles can produce an allergic reaction that causes an itchy red rash which can be very irritating.
The Juniper was voted the best plant for cascade style bonsai in our March '99 survey.
Interestingly enough, Indoor Bonsai for Beginners doesn't even list junipers in its A-Z of indoor bonsai species. While some believe junipers survive just fine indoors, others believe they definitely fall into the category of an "outdoor bonsai."
Hmmm. I wonder if I should pull my Anniversary Juniper from my office and replace it with - what the book defines as - an "indoor species" of bonsai. I would like to actually grow my next bonsai.
Speaking of growing bonsai, I've added a tree seed company to my list of bonsai stores. I linked directly to the Angelgrove Tree Seed Company page containing seeds for growing bonsai.
Also, if you're interested in growing a juniper, Bonsai Boy has a juniper bonsai starter kit for $24.95 + shipping.