I live on Vancouver Island and am looking for a good reference book on the care and maintenance of perennials/shrubs/trees,etc. once they have been planted. I can find lots of reference material on how to plant but cannot seem to find a good source on how to actually care for plants once established, particularly when they suddenly stop doing well and need to find out what has gone wrong. Would appreciate some suggestions on a book I can cozy up with on the couch on a rainy, cold, blustry day when I can't get into the garden. Thanks!