Figuring out what to grow in the shade is challenge enough. Throw in factors that affect southern gardeners, and the topic becomes as thorny as wild blackberry. Shade varies at different times of day, and gardeners need to take this into account. Shade changes from season to season, too, even within the same yard. In "Southern Shade: A Plant Selection Guide," landscape expert Jo Kellum takes the mystery out of the murky parts of the yard. Some plants desire rich, moist soil, decaying leaves, and just a bit of sunlight that filters through leafy tree canopies. Others need shade all day long. Still others thrive in morning shade followed by afternoon sun or the reverse. Sometimes the soil beneath trees can be notoriously dry where tree roots absorb all the available moisture. Jo Kellum lets gardeners know what to grow in the gloom and illustrates her choices with over two hundred color photographs. Homeowners need advice about landscaping workhorses for the shade-trees, shrubs, groundcovers, and vines-in addition to annuals and perennials. Unfortunately,"shade gardening" seems to apply mainly to dainty plants that don't solve the problem of how to fill a wet, shadowy spot or how to block the view of the neighbor's air conditioning unit. "Southern Shade" helps the gardener pick the right plant for the right kind of shady area. There are recommendations for little flowers, big trees, and everything in between. Jo Kellum's advice is simple enough for beginners yet complete enough for professionals. It makes an ideal companion when shopping. For those facing both shade and sun and looking for ideas suitable for sunny spots, Kellum has also written "Southern Sun: A Plant Selection Guide." Jo Kellum is a landscape architect, writer, and photographer based in Signal Mountain, Tennessee. She has authored regional editions of "Landscaping 1-2-3" for Home Depot Books and gardening and landscaping titles in Ortho's All About series. Her work has appeared in "Southern Living," "Landscape Architecture Magazine," "Country Gardens," "Renovation Style," and other magazines.