The Garden Corner by Sharon Allen Apologies
First of all, to those of you who purchased plants marked "Catsfoot" from the spring plant sale I apologize! You probably realized by now that they are plain ordinary snapdragons. I should have guessed that they were mislabeled when the leaves did not match the reference books' descriptions.
The mistake was not clearly evident until they bloomed, and of course I had planted them in all the wrong places. Perhaps the mislabeling occurred from their closely spelled botanical names (Snapdragons are Antirrhinum and Catsfoot is Antennnaria).
This time of the year we all feel like flopping in the heat, unfortunately plants that flop can become eyesores in our lovely landscapes. Several of the reasons that plants flop include: high humus levels in the soil, excessive moisture, too much shade, and/or planted too closely. While none of these attributes are negative, they can cause some plants to grow too tall too fast.
One way to combat the "flops" is to analyze your site and put plants in that like the available conditions. Another way is to divide the plants in the spring, making them smaller and less likely to flop.
The other method for controlling the "flops" is trimming the plants back early in the season. Since pruning perennials is not an exact science, experimentation is required. Effects may vary year to year depending on the weather, health of the plants, and soil conditions.
An extra dose of water and compost will help plants recover. Don't worry if you pruned something that you should not have. The worst that could happen is that the plant skips a season of bloom. Leave it alone the following year, and it should bloom for you once again.
Bloom time is delayed in perennials that are pruned. This can be a desired effect if you want, for example, your purple coneflowers to bloom when the blue asters do.
Plants to prune for height and bloom time include: Aster, Balloon Flower, Bee Balm, Dianthus, Gaura, Mallow, Penstemon, Purple Coneflower, Russian Sage, Shasta Daisy, Sneezeweed, Spike Speedwell, and Willow-Leafed Sunflower.
Plants not to prune to change bloom time include: Astilbe, Bear's Breeches, Bergenia, Bleeding Heart, Coral Bells, Hosta, Oriental Poppy, Peony, and Siberian Iris.
Pinching (removing the bud at the tip of the plant) can be done with your fingers. You may pinch your plant back again in a few weeks if the plant isn't short enough or if the flower buds are forming earlier than you would like. Cutting back is a bit more drastic than pinching in that you remove more of the plant.
I usually cut the stems back by about half. Sometimes I only prune half of the stems, extending the bloom time.