Gardening is fun, exciting, and sometimes devastating. While Chuck and I were on vacation this year a devastating disease snuck into Midland and killed all of the impatiens.  When we got back from vacation Chuck had to replace all of the impatiens that he had planted.  I thought mine had missed the bullet but I had to pull them all out yesterday.  The disease is called downy mildew.  Downy mildew is spread by water and water droplets.  So when we have plenty of water the spores scoot around and spread their little fungus bodies all over the place.  When its dry like the recent drought we had the fungus forms an oocyte that can live in the soil for up to 10 years until conditions are right again for them to start spreading out.  The symptoms are leaves dropping off the plant until the entire plant succumbs.  If you look on the undersides of the leaves you will find small white specks.
     Next year there will probably not be any impatiens on the market with the exception of the Sunpatiens and New Guinea Impatiens which are immune to Downy Mildew.  Do not confuse Downy Mildew with powdery mildew.  A lot of plants are susceptible to powdery mildew which will not kill a plant unless it is a really heavy infestation.