Answer: Without knowing which plant you are growing in topiary form it is a bit difficult to be specific, so here are some general pointers. During the winter, most plants used as topiary will appreciate a cool, bright location with ample humidity. The soil should be kept moist but not sopping wet, and fertilizing should be reduced or stopped during the winter months. The plant will naturally slow its growth for the winter and pick up again in the spring. When this happens, fertilize more often according to the label instructions and increase the watering proportionately. When the plant is in active growth you will need to trim it back lightly but frequently to maintain the topiary shape.
I located two sites on the web that may be able to offer you more information and guidance.
The Samia Rose Topiary is in Encinitas, CA. Information about their classes can be found on the web, by phone, or email. (800) 488-6742 http://www.srtopiary.com/classes.html E-Mail: firstname.lastname@example.org
A complete link to larger shrub topiary is found at http://www.geocities.com/RainForest/Vines/8433/links.html
This site also offers an email address and may help you locate the kind of classes you are wanting. Good luck!
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