Flowering Dogwood trees are easily grown from seed, however, the overwhelming majority of the sprouted seedlings will end up being Cornus Florida, also known as the White Flowering Dogwood. It matters not whether the seeds you have collected are from a Pink Dogwood or White, the offspring in virtually every case will be White Dogwood.
There is only one absolute way to reliably reproduce a Pink or Red Dogwood, or any of the varieties with variegated leaves. That way is by budding or grafting the variety you want to clone onto a White Dogwood seedling grown from seed. Cornus Florida Rubra is the botanical name for the Pink Dogwood tree. Cornus indicates Dogwood, Florida is White, while Rubra means Red or Pink. Therefore, Cornus Florida Rubra is used to identify a Pink Dogwood that has been budded or grafted to and grown on a White Dogwood rootstock.
Comparing budding and grafting, the propagation method of budding is the most commonly employed technique in the nursery industry.
Grafting is generally undertaken in the late winter months when plants are asleep, or dormant. Grafting entails first removing a small branch between 4 and 6 inches in length from the variety to be reproduced. The next step is to scrape the end of the branch, exposing the tissue under the bark while shaping a tapered end. Then, on the seedling that will be serving as your rootstock, you notch the seedling in a shape that will closely match to receive the branch you are grafting onto it. The success of grafting requires precise timing, temperature, and humidity control, and greenhouses are usually employed to achieve the necessary environment.
Budding, on the other hand, is much easier. A greenhouse is simply not necessary. Generally, budding is undertaken late in the summer when the seedling bark easily slips. What this means is when the bark of the seedling is cut, it is easily pulled apart from the underlying tissue beneath the bark. This underlying tissue layer is the cambium layer. In the northern U.S. states, crabapple trees and other fruits are generally ready to bud between mid and late July. Dogwoods, on the other hand, are not usually ready for budding until late August.
Grafting trees and plants require using a small branch that is attached to the seedling. With budding, you simply insert a bud under the bark where you want new growth to begin, usually on the lower portions of the seedling close to the soil. It’s not that you can’t bud on the upper sections of the seedling, but any new growth that appears naturally below your bud must be cut away as it will grow as rootstock and not as the budded variety.
To get started, just cut a branch off of the tree you want to propagate. This branch is called a “bud stick” due to the many buds on each branch that can be used to bud. The buds are found at the base of each leaf site. If you closely inspect where the leaf emerges from the branch, you will see a tiny bud. When the tree falls dormant in the autumn, the leaves will fall off and the buds will remain. If left to nature, the bud will grow into a new branch the following spring.
However, when you insert that bud just under the bark of a compatible seedling, the bud will grow into a new branch the following spring as if it were still on the parent plant. Most importantly, the budded branch will bear all of the same qualities as the propagated variety. Almost all ornamental and fruit-bearing trees are propagated by this method.
All you have to do is make a “T” shaped incision in the bark of the seedling. The horizontal cut should be about ¼-inch long, and the vertical downward cut should be about ½-inch long. As the name implies, the two cuts should connect at the top of the “T”. You shouldn’t cut into the cambium layer. Rather, slice the bark ever so slightly and open it with a knife or razor blade.
The next step is to remove the bud from the bud stick. From the bud you’ve chosen to remove, snip off and throw away the leaf, making sure to leave the leaf stem attached to the bud stick. It makes a dandy little “handle” for the bud stick.
After you’ve removed the leaf, cut into the bark just under the bud, which should easily pop off. We don’t want to cut into the cambium tissue, just make sure your cut is under the bark deep enough so the bud isn’t damaged. Properly cut, you should have a small piece of bark shaped like a tiny crescent attached to the stem from the leaf.
Holding our newly separated bud by its stem, gently slide it into the groove of the “T” shaped cut made on your seedling. It is important that it be placed right side up. The stem should protrude through the slit at an upward angle toward the sky. Be sure to slide the bud all the way down into the slit by pushing the bark, being careful not to cut the bud, with the tip of your knife.
Next cut a 1/4-inch wide rubber band so that it is no longer looped and use it to wrap around the seeding to keep foreign objects from the wound. Make a single wrap just below the bud and several wraps above the bud, being careful not to wrap too closely to the bud, or too tightly. We don’t want to suffocate the seedling, as it needs exposure to the environment so that the new bud will bond to the cambium layer of the seedling.
Now go enjoy winter. When early spring arrives, remove the rubber band and snip off the top of the seedling just above the bud. The bud will begin to grow into a new branch as the plant comes out of its dormant period as if it was still attached to the mother plant. However, this branch is now going to form the stem of a new tree as it grows upright.
After this budded branch grows to a height of 3 to 4 feet, clip the very tip off. This simple prune will force the branch to start producing lateral branches. After the lateral branches reach 18 inches in length or so, prune the growth from the stem below where these newly formed lateral branches begin. Your budded branch should now look just like a Mini-Me tree!
Pink Dogwoods can be propagated by taking cuttings and rooting them with the assistance of propagation misting. It is a tricky process though which is why the vast majority of nursery operators still bud them.