Two questions regarding Jubilation Gardenias:
1) When do I start pruning them?
2) How do I prune them to get the lower full branches?
I just purchased 5 Jubilation Gardenia bushes. I have them planted in my front bed. I eventually want to prune and shape these bushes but I’m unsure of when I should initially prune them and when I should start shaping them. Also, how do I prune them to get the lower, fuller branches so they’re not top heavy and bare at the bottom? They are about 1 – 1 1/2 ft tall. They top out at 4 ft and with a 3-4 ft width.
This article will help you understand the general needs of gardenias: https://www.gardeningknowhow.com/ornamental/flowers/gardenia/when-to-prune-a-gardenia.htm
The variety information on 'Jubilation' indicates they should be pruned in the spring.
To develop branching on the lower part of the plant, you're going to want to keep the top and sides trimmed, both to let more light into the lower areas, and to encourage branching on the lower branches. This article will give you a start in understanding pruning and shaping: http://pubs.ext.vt.edu/430/430-459/430-459.html