Grafting Means You Too Can Make a Tree
Joyce Kilmer ended his ode to trees with “But only God can make a tree.” Well, starting with just a few raw materials, you can also make a tree--by grafting.
The tools of grafting are simple. All you need is a sharp pocketknife, rubber bands and either plastic wrap or pruning paint, such as “Tree-Kote.”
Grafting is a process whereby a length of stem--called the scion--is severed from one plant and joined to the stem of another plant--called the stock--that is growing in the ground or in a pot.
The stock, which might be a small or mature plant, furnishes the root system that will nourish the scion. The scion can be nothing more than a half-foot length of stem.
Among the many types of grafting, whip grafting is one of the easiest, and is appropriate for the time of year when plants are just leafing out. The best size stocks and scions for whip grafting are one-fourth to three-eighths inch in diameter.
The closer the botanical relationship between the stock and the scion, the better are the chances for a successful graft. For example, apple scions are compatible with apple stocks, and red maple scions are compatible with red maple stocks. In addition, plum and peach are close enough kin to graft together, as are pear and quince. Not apple and maple, though.
Once stock and scion are chosen, there are two requisites for success: intimate contact between the cambiums of the stock and scion; and a careful avoidance of any cut surfaces drying out. The cambium is the growth layer just beneath the bark. When the cambiums of the stock and scion are brought together, cells in this region divide and knit together.
Now you are ready to graft. Take the scion and at its base make a sloping cut about an inch long with the knife. Make a similar cut on the top of the stock. Match the diagonal surfaces and hold them together while you wrap a cut rubber band around the union to hold the two pieces tightly together.
If the stock and scion are not the same diameter, match their cambial layers along one side and then bind them together. Finally, cover the graft with the plastic wrap or pruning paint to prevent any drying of the cut surfaces.
That is all there is to whip grafting, except to wait and watch. If the graft is successful, one or more buds on the scion piece will push out and grow within a few weeks. When this occurs, slit the rubber band wrap along the length of the stem to keep the stem from being strangled as it thickens.
Because trees elongate by growing from new buds on their stems--rather than by pushing up from below the ground--all new growth above the graft will be the scion variety, and the whole plant below the graft line will always be the stock variety.
You may wonder what the purpose is of grafting. First of all, it is fun. Second, it is a way to propagate any plant clone--such as Macintosh apples, Blue Point juniper or Scarlet Glory birch--that does not root easily from cuttings. Do you know of an old abandoned apple tree that nonetheless bears tasty apples? Grafting is the way to get it to your backyard.
Grafting is also a way to change the form of a plant. By grafting a scion of a weeping cherry onto a tall stock of a non-weeping cherry, the weeping cherry is elevated to a height from which it might gracefully cascade, rather than creep along the ground.
