PLANNING IS CRUCIAL
We have all seen the results of forest trees mistakenly planted underneath a house window or by the front door. The same mistake can be equally unfortunate in the planning and design of a shrub border. There is so much information out there that it is better to shop around a little to avoid botanical disaster. Impulse buying or settling for so-called excellent substitutes is always a mistake when it comes to buying plants. Developing a flowering shrub border is a long term and expensive project, and you have the right to specific information before you buy. Don’t go with the idea of bringing plants straight home. Acquaint yourself with the nature of the plant’s growth, its mature size, soil preferences and sun/shade requirements to avoid mistakes. Rhododendrons, for example, come in both huge spreading and small slower growing varieties.
Take your time and spread the work out, if possible. A large suburban border may take several years to create, but the process is not frustrating since the first bushes are producing bountifully before the last go in. This produces a sense of reward and satisfaction from the beginning.

DESIGNING THE BORDER
The first step is to lay out the shape of the border and decide the finished shape and size. To add style to a yard, the front of the shrub border is more successful when curved in ripples and bays. This effect is important for borders that are enlargements of old boundary plantings as the only way to eliminate the straight lines of original plantings.
The problem with these horticultural sweeps is to make them bold enough, yet remain in proportion to the rest of the yard. Small curves look accidental and ineffective while a curve too large to allow for an equally dramatic reverse curve misses the point. The trick is to find a happy medium.

Lay out the shape of the border with garden hose, which actually sounds simpler than it can be. Hose can be uncooperative and laying out curves with stiff plastic is not a job to be undertaken in cold weather or without patience. The line and curves will be visible and adjustable, however, and the effort will be worth the trouble. Look at the line you have laid many times from all angles before actually digging the ground.

You need to be sure you like the shape, that you have room enough for the plants to expand and that it serves your purpose, whether for outline, or screening. Look at the design from an upstairs window, if possible. A birds eye view will also let you know if the design meshes well with the rest of the yard. Shrub borders do not look their best floating aimlessly, they need to be anchored to existing structural or horticultural features.

Once the curves are correct, peg the final shape of hose down with lengths of wire cut from coathangers. This is necessary so your line does not get changed inadvertently by dogs or children.

PLANT ARRANGEMENT
Once the curves and size are fixed, strip off the grass or weed the open area where the border will be. The ground can be prepared and kept in excellent condition by laying a thick layer of compost covered with mulch. This defines the shape immediately and makes it a pleasant feature before the shrubs go in.

Experiment with where you want to set the plants so they will look their best. Color code stakes (blue: tall evergreen, pink: medium flowering shrub, green: spreading evergreen) and hammer them into the ground in groupings, rearranging them until you like the effect. This is where preliminary knowledge of growing habits is important. Rearrange the stakes as often as necessary, knowing how much space to allow between the various colors. The ultimate success of the border depends on how the material is arranged and that can take time. Preparing the ground in the fall and rearranging the stakes over the winter will give you time to get the best arrangement. Once you have it down, draw a plan. When you begin planting, use the plan, but also consider it as a guide since things change sometimes when plants start going into the ground. Be prepared to make adjustments without abandoning your original concept.

If you decide to skip the stakes and arrange the plant material when it is delivered, it will be more difficult to make a calm assessment of where the plants will look best. Dragging around heavy bushes with roots in burlap is difficult and handling them by their necks doesn’t do them any good. The tendency is to say “This will do” and that’s not the best use of expensive plant material. Planting the shrubs far apart may looks ridiculaus at first but with proper planting and being allowed to grow at will, the shrubs will fill the open spaces faster than you realize. Crowded plants lose their graceful form and degenerate when having to jostle for light and air.

ACCENT TREES & PRUNING
Don’t overlook small flowering trees such as dogwood and crabapple as excellent accents in the shrub border. These specimens look best when brought forward into the outer curves and allowed to dominate the surrounding area. High pruning these ornamental trees of all branches lower than five or six feet will allow room beneath for flowering shrubs like forsythia, rhododendron, spreading yews, spiky evergreens, spirea and hydrangea.

Even an informal border needs to be controlled by pruning. Pruning is another area where informing yourself ahead of time will avoid disaster. As a general rule, all spring flowering shrubs should be pruned immediately after flowering, as they set their buds for the following year during summer and fall. Summer and fall flowering shrubs can be cut back hard in the spring to encourage flowering on new growth. Prune selectively with the natural shape of the plant in mind to keep the border thriving and under control.

Robin Milliken is a Landscape Specialist and Master Gardener
The Master Gardener appears monthly in The Olathe Daily News.
© H&R Lawn and Landscape

Click here for Part I - Plant a Flowering Shrub Border

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