British Columbia: Best time to prune Yew in Surrey, BC

I just bought (June 27) 24 brown's yews from Cedar Rim Nursery in Langley and I'm getting ready to plant them along an ugly chainlink fence next to my home in Surrey. I want to train the plants into a formal hedge about 24" wide X 60" tall. I've dug out an area that is 52' long X 42" wide X 14" deep. I filled the long hole with a garden mix soil. I plan to space the plants about 27" apart. The 3 gallon potted yews are 3' tall. Most of the growth is at the top with not much at the bottom. Should I prune these plants soon after transplanting them into the ground to encourage more bottom growth? When should I be pruning to get these plants off to a good start. I also plan on putting a few handfuls of bone meal in the planting hole before filling with soil and watering in. Does this seem to be the correct way to plant these yews?