Flowering shrubs available for our Central Minnesota region are numerous. They are excellent for landscaping as we can choose small, large, any color and adaptability to various soil conditions. The greatest problem we can have is not choosing the right size for our landscaping needs. You must consider mature growth when planting.
Lilacs are the most popular, very hardy and applicable to many conditions. They do need a sunny location to produce blooms. The greatest problem with lilacs is their prolific growth. They easily get out of bounds.
Pruning is the key. You can cut tops and shape as you do evergreen shrubs, but you would lose the following years bloom. To prune a lilac and preserve next seasons flowering, cut off the tallest branch or branches to the ground. This must be done immediately as blossoms decline before next years buds have formed. This method is applicable to almost any blooming shrub.
Hydrangeas and azaleas are flowering shrubs that do well in shade or part shade. The azalea is a warm climate plant and was not hardly until the University of Minnesota developed “Northern Lights.” It still needs a protected location and an acid soil. The hydrangea is very hardy and will grow in many locations. There are many varieties in many colors, sizes and shapes. It loves Minnesota winters, but prefers an acid soil.
A favorite hydrangea in this area is the Anabelle. It has huge balls of pristine white flowers that will change to lime green and then tan in the fall. A beautiful plant all season. It tends to droop as the florets are so heavy stems need support.
The branches can be cut to the ground in fall or left on. It blooms on old and new wood. There is a newly released version of Annabelle called “Incrediball.” Growers claim stems to be much stronger and blooms larger.
When planting a hydrangea or azalea, work aluminum sulfate into the hole and then add one cup sulfur per plant. Sulfur is a slow acting, longer lasting acidifier that lowers the pH for any plant needing an acid soil, even blueberries. Blueberries are another pretty shrub that is a nice form, is small and turns a beautiful red color in fall.
Viburnums are another popular shrub. I have “Snowball,” that is covered with white perfect balls of iridescent white, smaller than Anabelle. It will grow out of hand, but slower than the lilac. It is pruned the same.
Spireas are also very popular and hardy, not fussy about soil conditions and bloom consistently. Spireas vary in size and are very hardly. Seen in landscapes often is Spirea Van Houtte. It is a weeping bush that never goes out of bounds getting about 4-feet tall. It is superb, with the arching branches covered with flowers along the entire stem.
A few shrubs get tall and need to be left to grow as they wish, but they need space. One very enchanting tall shrub is Tamarix. It grows very tall and has bright eye-catching pink feathery spikes all summer. It is claimed to be invasive, but I have not found that true. The flowery spikes are delightful in making arrangements. The foliage is also fine textured and intriguing.
Recently experts tell us of a new method of planting trees and shrubs. When digging the hole, dig only as deep as it is in the container, but go wide to give roots room to grow outward. Another bit of new information, it is recommended not adding soil amendments to the planting hole. It seems roots tend to stay within the added soil and they need to extend and grow into the natural soil that surrounds the bush or tree.
Betty Winscher is a Master Gardener and can be reached at (320) 584-8055 or via e-mail at [email protected]