Woodland habitat garden on the banks of Powder Creek
Powder Creek is situated in the bluff woodlands of St. Clair County, Illinois. The bluff woodlands create a unique ecology which can be distinguished from the Mississippi bottoms to the West, the once extensive tall grass prairie to the North-East, and the hardwood forests to the South. Locally, in St. Clair County, the bluffs are characterized by moderately steep ridges and ravines populated by woodlands peppered with remnant hardwood forests and related understory plants. The inherent beauty of the bluff woodlands creates an ideal location for building homes and subdivisions. Urbanization has led to the naturalization of many exotic plant species that compete with indigenous species. We know, thanks to research by ecologists like Doug Tallamy, that indigenous plants play a critical supporting role to a complex matrix of creatures and our preferences for certain exotic plants tend not to support much, if any, wildlife. As gardeners and garden designers, we have the authority to wield the trowel and the shear, in other words we are at the grass roots of a project that can yield great benefits to pollinators, and bird species.
The site at Powder Creek is located just East of the confluence of two sections of creek which skirts the house on three sides The proposed habitat installation zones stretch from the West side of the house (A), to the confluence and East along Powder Creek (B) until reaching the property line on the East side of the house (C). The homeowner is a dedicated gardener and has installed extensive gardens that mix ornamental species with native cultivars to great effect in a multilayered and naturalistic plan.
The project proposal focuses on the areas outlined for the express purpose of creating a series of habitat gardens that introduce a diverse set of indigenous understory and edge species using local forest remnants as a guide and genetic source. The restoration zones represent a significant percentage of the total lot. The proposal is not to cover every square inch of zones A,B,C, rather these zones represent the total areas of activity in which this proposal is focused. The proposed restoration design/planting plan would involve sketching out a strategic process that would remove certain species and "stitch-in" native plant material using a combination of fully fledged plants, plugs, and seed. In other words, the archetype for the project is an exceptional woodland understory not a conventional mulched garden bed.
Zone A is located on the West side of the house and skirted by Powder Creek. The area is part shade and currently dominated by ornamental ground covers, most notably Vinca (Periwinkle). Zone A presents the opportunity to remove a large percentage of existing ground cover and spontaneous tree saplings and install a mix of flowering edge species and woodland grass and sedge. It is important to note that by moving toward a more focused native plant palette is not to suggest that the goal is to eliminate the existing plants. Rather the goal is to carve out space to build a new plant community that is resilient enough to integrate with, and push back against existing plants.
Zone B is largely characterized by a swale in full shade and also features a utility ROW. Toward the creek there is a bit of dappled sunlight which might be enhanced with the removal of a few small trees. The plant palette could make use of woodland grass and sedge, ferns, indigenous plants that are "heavy lifters" but not showy, and spring ephemerals that take advantage of an empty deciduous spring canopy.
Zone C provides the best opportunity to get a variety of blooming natives as it the area with the most sun exposure. Currently there is a rather impressive and healthy looking stand of pachysandra located at the Eastern portion of the zone, a type of Japanese Iris that works well against the creek, Hibiscus syriacus (Rose of Sharon) and several recently planted Fothergilla. It does not seem worth the effort to try and eliminate the existing plant material, instead it will be best to take a surgical approach. In other words carve out areas to insert dense native plantings that can "push back" against established plants.
Powder Creek Native and Naturalized Plants
A Brief Look at St. Clair County bluff woodland species
The approach to plant material is all at once focused on underutilized and overlooked native understory species as well as ornamental naturalized species. Whereas we recognize the importance of using native plant species it is only realistic to accept that exotic species are here to stay. The proposal is not interested in plant purity, so to speak, rather the goal is plant communities. This means that the overall philosophy regarding plants is "if you can't beat em', join em'". Our preference is multilayered native plant communities that are resilient enough to integrate with existing ornamentals.
Habitat gardening differs from traditional bed planting in that it accepts a degree of wildness. Although it remains consistent with convention in that it remains focused on maintenance. But, how we maintain is an important distinction. Like conventional gardeners, we are still very interested in aesthetics. Design (color, form, texture,etc.) remains a primary motivation but our aesthetic goals are integrated into our goals to create habitiat. For example, Conventional gardener might experience some anxiety over a certain insect eating the hostas or a plant that is out of place in a neatly spaced and mulched bed, but habitat gardening aspires to these things. Insects and deer eating the plants is tolerated and encouraged, that's the point, and weeds become less noticeable because they no longer seem out of place within a more naturalistic framework.
That being said, habitat gardens still require maintenance. But perhaps maintenance in this case is best understood as management. The most critical time for new habitat installations is the first year when special attention should be paid to allowing the new congregation to become established. This means making sure plants have adequate moisture and are not being overly pressured by existing plant communities. These activities should probably be done on at least a monthly basis. After the first season, habitat gardens become significantly more autonomous and require only seasonal attention.