Delightful dogwoods

Wow, weren't the dogwoods gorgeous this year? I think their bracts had more color intensity and were larger than normal because of all of the spring moisture. Unfortunately most of the dogwood "flowers" have faded and shriveled by now.

So why do I write about dogwoods after their time in the spring flora limelight? This spring, I heard several disconcerting conversations among amateur gardeners about dogwoods. Several gardeners would not consider planting dogwoods in their landscape because the last two or three that they planted died within the first two years after planting. They concluded dogwoods must be very finicky.

Even professional horticulturists are gun shy about dogwoods. I recently visited with a cousin who lives in northwest Missouri. The nurseryman in her hometown would not even consider selling her a dogwood unless she planted it in the shade. Because he had experienced such high mortality from dogwood plantings, he discouraged anyone from planting dogwoods unless they were planted in what he considered the perfect habitat.

I think that dogwoods are getting a bad rap. I hope to set the record straight and encourage you to plant dogwoods, one of our most beautiful native flowering trees.

Garden vs. natural habitat

Let's look at the ecological setting surrounding dogwoods growing in the wild. First, you will notice that most native dogwoods are growing under the shade of much larger trees such as oaks and hickories. This would suggest that dogwoods require shade in order to grow vigorously. I would agree with you, except that every dogwood I see lined out in a field at a nursery is growing extremely well under full sun conditions. Therefore, dogwoods can tolerate full sun.

The native forest floor is covered with dead leaves and twigs. This organic layer is usually several inches thick. Therefore the roots of native dogwoods are accustomed to having their root system covered with a heavy mat of organic matter. This mulch layer keeps the roots of dogwoods cool during the summer and warm during the winter. In addition, this mulch layer helps hold moisture in the soil during extremely dry conditions. As the leaf matter on forest floor decomposes, the organic matter is slowly mixed with the natural mineral soil through the activity of small mammals, insects, and microorganisms. This slowly enriches the soil under the canopy of the forest. Dogwoods are usually found in parts of the forest where the better soils are located.

Research by a friend of mine corroborates the notion that soil amendments and mulching are extremely important to dogwood survival, especially under landscape conditions. He planted dogwoods in his yard under full sun conditions. He enriched the soil where he planted the dogwoods with peat moss. He then placed four to six inches of mulch around each tree. He made the mulch bed about one and one half times the diameter of the drip line. He did not let the soils under the mulch dry out. On the other hand, he did not keep the soil soggy. His dogwoods grew very vigorously.

Insect infestations

It is interesting to note that dogwood borers are often found in dogwoods growing in landscapes, yet they are not found very often in dogwoods growing under natural conditions. Insects can sense when a particular tree or plant is under stress. They often move into that particular plant and make it their new home. I think that most dogwoods under attack by borers are not growing vigorously, but are under stress.

If you want to be successful in growing dogwoods in your landscape, there are a few things that you can do to increase the chance of survival and insure that the specimen is growing vigorously. First, you must plant your dogwood properly.

I have often written about proper planting procedures. Dig a hole two times the diameter of the root ball or root wad of your nursery tree. Take the soil out of the hole and mix it with peat moss in the ratio of two soil to one peat moss. Next place the root wad of the tree in the excavated hole. If the tree root system is balled and burlapped, you can immediately backfill. After backfilling, cut any string that may be encircling the tree stem. If the tree came from the nursery in a pot, remove the root wad from the pot and shoot a jet of water at the root wad so that you remove an inch of soil all the way around the root wad. You want to loosen up the roots and get free root ends projecting out from the root wad. When you backfill with the soil-peat mixture the free tree roots will already be teased into the new soil.

Keep fertilizing

Completely back fill with the soil-peat mixture and form a well of soil around the tree stem. Then water thoroughly the newly planted tree with a solution of root stimulator in water. Place enough water on the tree so that the root ball or wad, the backfilled soil and the undisturbed soil around the hole is mushy. Next place a four- to six-inch layer of mulch around the tree. Make the diameter of the mulch circle at least one and one-half times the diameter of the drip line.

Continue to use root stimulator for the next two or three times that you water after planting. Later on, you can use a tree and shrub fertilizer in early spring and early fall to enhance soil nutrition.

After initial planting it is important to monitor the soil moisture conditions around the newly planted tree, especially the first one or two years. When the soils surround your dogwood are wet, don't water. When you notice that the soils are beginning to dry out, water so that you can get the equivalent of a 1- to 2-inch rainfall.

As the years progress, slowly enlarge the mulch bed, continue to fertilize in early spring and fall, and monitor soil moisture on a regular basis. If you follow the above instructions, I think you can be successful in growing beautiful dogwoods in your landscape. Happy dogwooding.

Send your gardening questions to Paul Schnare at P.O. Box 699; Cape Girardeau, Mo. 63702-0699 or e-mail him at news@semissourian.com.