I want to develop the back of our yard into a new garden, but it is a hillside. Do you have advice for planting on a slope?
Answer: Hillside gardens can be beautiful and dramatic. They are especially effective when the slope faces a viewing area—for instance, if the garden slopes from the front of the house to the street, or if a back porch or deck faces a slope at the back of the yard. Although the slope presents some maintenance challenges, a hillside garden can actually be easier to tend than a hillside planted with a lawn that would be difficult and dangerous to mow.
It can be a little tricky to garden on a slope, but with the right preparations and plant choices, you will be successful.
General points to remember:
1. A slope offers nowhere to hide. All the plants will always be in view. Stick to plants that look good throughout the growing season—for instance, stay away from spring ephemerals that die down after their early bloom—and include some evergreen plants.
2. Include a path to the top, which will allow you access to maintain the plantings and visitors a chance to look at the garden and surroundings from a different point of view.
3. On a very steep slope, you may need to include stair steps instead of a path—and have a series of terraces for planting built into the slope.
4. Work with any existing stones on the slope, rather than trying to remove them. The same goes for shrubs and trees. Such stones and large plants may be holding the slope in place; removing them could trigger a landslide.
Preparing the slope for planting:
1. Remove any existing weeds or other unwanted plants (keep in mind #4, above).
2. Amend the soil and add topsoil if necessary.
3. On steep slopes, lay weed-blocking fabric before planting. Cut holes in the fabric through which to set the plants.
Since a slope can make routine maintenance such as watering, weeding and deadheading difficult, keep the planting simple and choose plants that will thrive in the site's conditions and the local climate with a minimum of care. Groundcovers and clumps of easy-going perennials will make the hillside garden both attractive and low maintenance. Daylilies, sedums, mums, asters and Shasta daisies, Siberian iris, bee balm and yarrows are a few perennials that typically do well on a hillside.
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