They are not heavy feeders. If you really feel yours need a boost, feed them in early spring and never later than July. Don t feed when planting, and only use fertilizers formulated for acid loving plants. They have a shallow, fine-textured root system, so don t go mucking around stirring up the ground under them. Because of their root system, however, they are easy to move and can be planted, in my area, anytime the ground isn t frozen.
Spring is best, with fall as a second choice where soil temps stay warm for a while.
Mulch is essential - keep it in place all year around to help keep the soil moist and cool for them. They want a highly organic soil and are not fond of heavy clay. In my garden, where heavy clay predominates, I have best results by planting high . If the soil is really bad or full of tree roots, I will scrape out a shallow depression and set the root ball in it, just about on top of the natural soil. If you don t have good rains once a week, you will need to water these plants, and especially when they are newly planted.