We occasionally receive calls from gardeners who want to know how to treat an apple seed so it will germinate. Usually, the gardener is trying to reproduce an old apple tree that was special for some reason (good quality fruit, planted by grandparents, etc.). Unfortunately, apples grown from seed will not be like the parent. About 1 in 80,000 apple trees grown from seed will be as good as the apples we are used to eating. Usually you end up with a tree that has small and inferior quality fruit. If you want a tree exactly like the parent, you must propagate that tree vegetatively. In the case of apples, this usually means grafting. Apple trees are easy to graft, even for novices. Don’t be afraid to try this even if you haven’t done it before. The step that needs to be done soon is choosing and cutting of scion wood or small branches that will be grafted on top of a rootstock. Here is the procedure.
The ideal branches for scion wood will be from about 1/4 to ½ inch in diameter. Good propagation wood can be made of water sprouts that grew from limbs in the tree or suckers that grew from the trunk. Water sprouts are those small branches that grow straight up from larger, more horizontal branches. If you use suckers, be sure the suckers are growing from above the graft at the base of the tree. This propagation wood is normally taken during February. These can be cut in lengths up to about a foot long. They can be stored in your refrigerator at about 40 to 45 degrees F. Do not freeze. The next step is to decide what rootstock you will graft them onto.
Fruit trees are normally grafted (or budded) onto specially selected rootstocks. These rootstocks normally reduce tree size. For example, a tree that normally would get 25 feet tall will only reach 10 feet if it is grown on a certain rootstock. Dwarfing rootstocks also allow apples to fruit earlier. A tree on its own roots normally takes 5 to 7 years before it will bear. Semi-dwarf trees bear in 4 to 5 years, and dwarf trees bear in 3 to 4 years. Unfortunately, dwarfing rootstocks are not well-adapted to Kansas. Semi-dwarf trees are usually a better choice for us. Note that rootstock reduces tree size, not fruit size. For example, a Golden Delicious tree that only reaches 8 feet tall due to a dwarfing rootstock will bear the same size fruit as a Golden Delicious tree that is 25 feet tall.
Most nurseries only sell trees that are already grafted. A company that does sell rootstocks is Raintree Nursery, Morton, WA, (360) 496-6400, http://www.raintreenursery.com/ Another is Cummins Nursery, (865) 233 3539, http://www.cumminsnursery.com though there is a surcharge on any tree that you order less than three rootstocks. If you know of other nurseries that sell rootstocks, let me know, and I will post them in later newsletters. It is also possible to buy a tree from a local nursery and graft your clone into it. One disadvantage of this method is that it is possible to prune off the special clone instead of the cultivar branches by mistake. For details on grafting or budding and care see the Missouri Extension publication, titled “Grafting,” which can be found at http://bit.ly/9SvHVo