Eliminate Floppy Perennials
Flopping perennials can ruin the beauty and enjoyment of your garden. Take note and prevent future problems with a bit of proactive care.
Make sure the plants are receiving the growing conditions they prefer. Insufficient sunlight, excess water, and too much nitrogen fertilization can cause plants to flop. Move plants to the right growing location and adjust care as needed.
Older plantings and overgrown perennials will often flop. Dig and divide to stimulate sturdier growth. Some perennials like asters and mums benefit from regular pinching to keep them compact and sturdy. Pinch these plants back to 6 inches throughout June. Russian sage should be pruned back to 4 to 6 inches above the ground in early spring. If plants still flop, cut them back halfway in June.
Autumn Joy sedum is another plant that tends to flop when grown in shade, wet or overly fertile soil. Prune plants back halfway when they reach 8 inches in height.
A bit more information: A cool wet spring can result in unusually tall perennials that are more likely to flop. If these perennials are normally compact and produced a great floral display you may need to take no action to correct the problem next year. A more “normal” spring should result in more typical growth.