Agricultural Sciences

Trees, shrubs, flowers allow gardeners to 'paint' a landscape

University Park, Pa. -- Many homeowners live in envy of those neighbors who seem able to turn a few trees, flowers and even rocks into an inviting outdoor scene. But you, too, can do it by following a few basic guidelines, according to a horticulturist in Penn State's College of Agricultural Sciences.

New or veteran homeowners hoping to enhance the look of their properties can use sustainable practices to express creativity, create habitat for wildlife and define special-use areas with year-round interest, said James Sellmer, associate professor of ornamental horticulture.

"If you consider your landscape to be like a painting, then you can picture trees, shrubs, groundcovers and herbaceous flowering plants as the 'paint' and 'color' elements that bring life, vibrancy, depth and structure to the masterpiece," he said.

"You can place trees to provide shade for seating areas and to reduce heat on the house with placement on the south and southwest areas of the property. Similarly, conifers can provide a windbreak against cold winter winds on the west, northwest and northern side of most properties."

Sellmer highlighted the basic components of garden landscaping:

-- Flowering trees and shrubs. These provide excellent structure for defining rooms in the landscape, such as entertaining areas, composting and work areas, play areas and vegetable gardens. They also provide focal points of interest if well placed and well chosen. The interest can change from season to season and from spot to spot in the landscape.

"Place your trees well away from sidewalks and sewer lines to avoid disruption in years to come when their root systems mature," Sellmer said. "Small flowering trees potentially can be placed under power lines, but you don't want shade trees growing into the lines, putting the trees at risk of being topped by the utility company. Do not plant them directly in front of windows unless you really just want to obscure the view out."

He warned against choosing plants not suited to the location's soil pH and hardiness zone, as well as those that will grow to a mature height and width greater than the area where they will be planted, which means severe pruning will be required down the road.

-- Perennial and annual flowers. Flowers can help add depth and ever-changing interest to plantings. Herbaceous annuals provide "punch" in the landscape. They can be used to highlight an opening to a path through the garden or lawn. They also can be used to attract attention away from a less attractive area.

"Annuals really are a very 'now' and very colorful exclamation point," Sellmer said. "They require replanting every year, so they do require maintenance, but in most cases, they provide color, texture and character as they grow into an area.

"Herbaceous perennials may flower early, middle or late season or bloom sporadically," he noted. "They should be planned to be showy and then fade away as others step forward to provide color and character to the landscape."

-- Ground covers. These plants act as a transition element from space to space in the landscape, tying together the rooms and areas.

"Ground covers provide a different character and texture," Sellmer explained. "They flower and tolerate shade, and once established , they generally require less maintenance than grass. You can mow some ground covers, such as sweet woodruff, in the late summer to reinvigorate it, but in most cases mowing is not necessary."

He said some ground covers, such as purpleleaf wintercreeper, may require pruning back. "English ivy receives a bad rap as an invasive species, but if you keep it on the ground and away from trees and buildings, in most cases it stays juvenile and is a very good ground cover.

"Many don't like common periwinkle, but it also can be controlled if you use it," he said. "Others can be aggressive and need strong boundaries like concrete walkways."

Sellmer said trees, shrubs, groundcovers and herbaceous flowering plants also can enhance the landscape for birds, the insects they feed upon and other wildlife.

"If you are interested in hummingbirds and live in a quiet neighborhood, there are plants that you can use to attract them, including glossy abelia, buckeyes, beautybush, lilac, chaste tree, yucca, hollyhock, columbine, begonia, bellflower, canna, bleeding-heart, purple coneflower, daylily, coral bells, hosta, lantana, lily, lupine and nasturtium.

"Fruit-bearing plants such as shadbush, blueberry and winterberry holly are excellent sources of food for catbirds, robins, cardinals and Baltimore orioles," he said. "Sunflowers are an extra-special, late-summer treat for song birds.

"Needle-leaved and broad-leaved evergreens provide protection and shelter. Perennial grasses, such as the big and little bluestem, hare's tail grass, tufted hairgrass, Indian grass and dropseed provide seeds, nesting materials and cover."

With so many options, the question for some novice landscapers is where to begin?

"I suggest taking a walk through your local arboretum or botanic garden," Sellmer said. "They're a great source of inspiration, ideas and plant names. After a few walks, it's time to investigate those plants and see if they will work where you would like to see them in your yard."

Penn State Extension's online resources ( provide information on size, seasons of interest, growing conditions and more. Penn State's Department of Horticulture offers numerous free publications on flowering shrubs ( that that can help in making decisions.

Penn State Master Gardeners ( also can give you specific advice on plants and availability in your area.

"Once you have a short list of must-have and suitable plants, I would take another walk through the yard to plan how you will arrange and prepare the area and then a final walk through your local garden center or nursery," Sellmer advised. "Garden centers and nurseries are a great source for further information.

"In addition, if the whole process is a little overwhelming, your local nursery or garden center can help find a landscape contractor that you can hire to design and install your masterpiece."

For more information, contact Sellmer at 814-863-2250 or

Placement of shrubs such as this lilac bush can personalize any home landscape. Credit: Penn StateCreative Commons

Last Updated July 05, 2011