Maybe it’s just me but every year at about this time, I get mad at poopy petunias and their daily need for water. The “thrill is gone” and this chore is just another task on my to-do list. If you can resist pitching your pots and instead trim them hard and feed one last time, you will have lush healthy blooms when the weather cools down. Think September, when you will once again enjoy siting outside on your deck or patio.
Another problem that crops up in late summer is powdery mildew. As the name implies, powdery mildew looks like white or gray powdery spots on plant foliage and stems. Although it won’t kill your flowers, it is rather unsightly. There are organic and conventional sprays for this nuisance but powdery mildew will go away when drier, less humid weather prevails. Trimming leggy, tired growth will encourage new clean foliage and flowers.