Crossville Chronicle, Crossville, TN

October 14, 2013

PLATEAU GARDENING: Planning a privacy screen 

By C. Rae Hozer
Chronicle contributor

CROSSVILLE — Finding the right plant and putting it in the right place isn’t always as simple as that age-old gardening advice sounds. A plant’s hardiness along with its sun, soil and moisture requirements determine how well suited it is to your site. When planning a new feature for an existing landscape, trees and shrubs already growing and thriving there are proven matches for conditions. What you need to know are characteristics like the mature size for existing plants because that affects how many other plants will be required to finalize the design and their most effective arrangement. 

A recent reader email with two photos attached asked for help identifying an evergreen growing in the backyard of the home they had recently purchased. The homeowners wished to add a privacy screen along the property line behind their house where the pictured plant was growing. It was described in the email message as a pine (either a bush or small tree). They liked the looks of that evergreen and were considering the purchase of 8 to 10 more from a local nursery. Being new to this climate and unfamiliar with many plants of the area, they had asked friends and neighbors, but no one they consulted could name the species. They wondered if I could look at the photos and name the mysterious evergreen. 

Landscape design considerations in this case: A screen is a group of plants arranged in a way that either blocks from your view sights or structures you find unappealing or that prevents others off-property from having an unobstructed look at the house and backyard. A good, well designed plan for one should consider how much area you are working with to help estimate how many plants at maturity will fit in that space, the current landscape style (or the look you or wish to create) and weigh the amount of time required to keep the plantings looking good against the hours and/or money the owners are willing to put into future maintenance. Those factors and the growing conditions help determine which are the best plants for the job, how many are needed and how to best arrange them.

Plant materials used should be tall enough to block the line of sight as desired but not so high and dense they keep the backyard in shadows. If the foliage is evergreen there will be a fairly uniform look year round. Deciduous varieties could be selected for ornamental features such as flowers, berries or other fruit, variegated leaves or unique and interesting branching and stems that produce seasonal variety. The screen could take the form of a hedge using the same plant species as the existing unknown variety of needle evergreen. Another option would be a border containing a mix of compatible plants — the existing evergreen as well as other shrubs and perhaps a clump or two of ornamental grass.

Typically plants in "formal" or "classic" style hedge are of one species, closely planted in a single line and sheared to create a geometric look. All that pruning is a lot of work. Bad pruning techniques commonly cause loss of foliage on lower branches which get too much shade. When sheared properly the top of the hedge will be narrower and the base wider so sunlight reaches all the branches. When needle evergreens are planted too close together and branches overlap there is a similar problem. The lack of sun causes bare twigs where needles drop. A more informal style hedge or screen can be achieved using a border planting containing a mix of plants selected to fit the space (when mature) with little or no trimming required. An advantage of an informal, natural looking style is that less pruning is necessary which means less time and money spent on maintenance.

• • •

Plateau Gardening is written by Master Gardeners for gardeners in Tennessee’s Upper Cumberland Region.  Contact UT Extension Cumberland County at P.O. Box 483, Crossville, TN 38557 (484-6743) for answers to horticulture questions, free publications and how to become a Master Gardener. Send email comments or yard and garden inquiries to Master Gardener Rae, MGardenerRae@frontiernet.net.