Shaded areas in the landscape may be difficult areas to grow turfgrass and vegetables, but offer an opportunity for a shade garden. Success in shade gardening is heavily influenced by plant selection and site preparation. It’s important to take time to count the number of hours of direct sunlight received by a site during the daytime, as well as when the sun shines on the space. For example, a site that gets 4 hours of morning sun and 5 hours of afternoon shade receives less solar energy than the opposite sun and shade combination. The morning sun site is often referred to on plant care tags and web sites as shade to part sun, whereas the afternoon sun site as sun to part shade. If no direct sunlight is received by the site during the day, it’s a little more straightforward; these sites are simply characterized by the term “shade” or “full shade”.
In addition to the direct sun consideration is when filtered or “dappled” sunlight is received. This is commonly the case when an overhead tree casts shade on the planting site, and patches of the area are in sun or degrees of sunlight during the daytime hours, but never in full sun or full shade. Of course, as trees grow, more and more sunlight is blocked gradually over time, requiring adjustments in plant material by the gardener.
Before planting, it is important to prepare the soil properly. Many of the plants that prefer to grow in shaded areas are native to woodlands where the soil is well drained and high in organic matter. Since shaded areas in the landscape often remain wet, a properly prepared soil will help minimize the potential for future crown and root rot problems. In most cases, best results will be achieved if preparation for the new flowerbed is started a year in advance. However, good results are possible if the process is started six months prior to planting.
The first step of soil preparation is to control any undesirable perennial plants. Once perennial flowers or groundcovers are planted, perennial weed control will be very difficult and labor intensive. Apply glyphosate herbicide to the flower bed before planting to help eliminate bindweed, dandelions, weedy grasses and other unwanted plants. Another approach is to “solarize” the site by placing clear plastic over the area for a period of 3 months which usually kills most weeds and undesirable plants.
The single most important factor of site preparation for shade gardens may be the addition of organic matter. Organic matter in a shade garden soil will improve drainage and more closely resemble the natural soil conditions existing in a woodland area. In general, an inch of organic matter should be added for every three inches of soil depth worked. If soil preparation is started a year in advance, either compost or aged manure can be used.
