I am having a terrible time growing flowering annuals. I have large clay planters and haning baskets with a drip system. The problem is, sooner or later things get too wet and stay too wet and then the fungus strikes. I am thinking the problem is drainage. The water isn't draining properly. The reason I say this is because of the 13 hanging baskets I have, several are healthy and several are sick or dead. They all get the same amount of water from the drip system. The drip system runs once a day. In the summer it ran daily and now it is running every other day. Fungus has killed my vinca all year long...one at a time. Here is a picture of one of the hanging baskets. As you can see, there are no problems with this vinca.