Question: Help! My Italian cypress are drying out and dying mostly from the top down. They have their own bubblers for water.
Major reasons for Italian cypress to die back: too much water — water deeply once three to four weeks in winter and no more than about once a week in summer. Too little water — sometimes people put these trees on just a few minutes of water from their drip irrigation system. Water should be applied so that it wets the soil 24 inches down to an area at least four feet in diameter around the tree. Depending on how quickly enough water from your drip system is applied, this might take up to several hours of watering .
Spider mites — this starts in hot weather, because that’s what they like. They’re usually a problem on trees that were under-watered. Spider mites like dirty foliage. Wash trees with a high- pressure hose nozzle after dust storms or a couple of times a year just to keep them clean. Periodic soap and water sprays are not a bad idea, either.
Borers — several people have reported borers in Italian cypress, but this has never been a common occurrence in the past. I could not find it reported anywhere else, either. Usually a soil-applied insecticide for borer control applied around the roots would be recommended if this were the case. Get your irrigation under control, and that should solve most of the problems.