I’ve mentioned deadheading* over-zealous native plants and weeds occasionally in my past posts, but today I wanted to talk more about its importance for maintaining control not only over the look of a more formal garden, but also the biodiversity of a planting using native species. There are some native plants species which are more aggressive than others. For example, Branched Coneflower (Rudbeckia triloba), sunflowers (helianthus sp), (silphium sp) and goldenrod (Solidago sp), just to name a few, produce a lot of seed.
Perhaps the photos above can explain better than I can with my words to what I am referring. This small rain garden was planted with the intention of keeping it more formal, more like a specimen garden so visitors could see how native plants could be used in a formal setting and also to help them better identify individual native plant species.
Caretakers used to regularly deadhead most of the blossoms of the more aggressive species as they were setting seed in late summer/early fall. It appears now maintenance of the garden is not being done regularly or at least not so carefully, so some of the less aggressive species are being overtaken by the more aggressive Sweet Black-Eyed Susan (Rudbeckia submentosa). The biodiversity of the original planting is now in jeopardy as well as the original design.
SEED FOR THE BIRDS
It is important to deadhead the more aggressive plants in your gardens to maintain the biodiversity and the design of your garden. But, if you want to save the seed from the deadheaded plants for the birds wintering over, cut the stems long enough so you can tie them up and put them out on your patio or hang from your shepherd’s hook during the winter months. Once your garden has become overwhelmed by the more aggressive species it will mean a lot of hard work to get it back to some semblance of your original design and biodiversity.
*Deadheading in this case means to cut the seed heads off the stems of plants before the seed can ripen and spread throughout the planting. Deadheading also means to remove dead flower heads from plants to encourage further blooming. And, it can also mean to cut back the stems of plants to make them come back shorter and bushier. This works well for the taller, wet mesic prairie plants especially since they tend to flop over from their heavy blooms.
This is so relevant to what I am dealing with at home and at a church property where I volunteer. Thanks for writing about it. My prairie planting has less diversity now than it did five years ago. Now the grasses are more dominant. Also, I bought a sedge several years ago which was labeled Wool Grass but turned out to be Scirpus atrovirens, dark green bulrush. Since it was taller than I wanted next to my small water garden, I transplanted it to the creek that runs through my property. Boy, was it ever happy! It is pretty much a monoculture now on the side of the creek where the ground is low and moist. It has eliminated some bad weeds but also pushes out swamp milkweed and other blooming plants. I can’t get it out, but wonder if you know of any plants that could compete with it for space.