Grafting techniques 101
During the colder months of the year what is a gardener to do? How about giving grafting a try this year. I know what you’re thinking — that sounds a bit too complicated or time consuming. Not really if we keep it manageable in small steps. Grafting is the transferring of fruiting or flowering stock, called scion, of a desired plant variety onto a root system, also termed rootstock, of another plant to make a whole new plant entirely. The scion has several buds on it and grows as the top of the new plant.
A few reasons to graft — to change a variety, to better vegetative reproduction, to change the root system from standard size to dwarf size, to add a pollinator to become a self-pollinator, to repair damaged on an existing tree, or to just create some new designs in the growth.
What is needed to graft? Rootstock, various scion wood, grafting tape or “parafilm” grafting wax, grafting tools such as an Omega cutter, a Scionon, a simple sharp knife or a box cutter can be used.
When collecting the scion wood keep in mind that one-year-old growth works best. It should be about the size of a wooden pencil in length and width along with at least two nodes present. Scion woods must be kept in a moist, not damp, paper towel and placed in a cold place or in a sealed Ziploc bag in the refrigerator. It should also be collected now while it is in the dormant season until February or March. You can also do active growth grafting, known as greenwood grafting, done during the months of June to early September, but for this article we will focus on the dormant bench grafting technique. Scions and rootstock may be ordered online from a variety of garden suppliers and nurseries.
It is best when they both are closely related within the same species since the cadmium of each must touch to produce a good graft.
The graft type to use depends on what size scion to rootstock is being used or if buds are added.
1. Whip or Whip and Tongue matches stems of equal size of both the rootstock and scion.
2. Cleft, which is used for trees that have 1-to3-inch diameter trunks or when the scion is smaller than the rootstock.
3. Bark, which is used for 3- to 5-inch diameter trunks.
Budding which has two types T-budding and chip budding where there is a transfer of individual leaf buds to the stem of another plant, for example used for peach and plum trees.
4. Four Flap or Banana graft that cuts the bark into four pieces of both the scion and rootstock then overlaps before wrapping.
Let’s whip graft by making diagonal cuts across the bottom of the scion and across the top of the rootstock. Place these two cut edges together to make a new stem. Cut a 3-6 inch strip of grafting tape and begin wrapping a half of an inch above the scion wood cut and wind it down to a half-inch below the rootstock cut. Do not wrap it too tightly to damage the bark but wrap it snug. Follow these steps for post grafting care guidelines.
1. Use a 3-gallon container for planting the graft plant. Place a tomato stake near for support.
2. For two weeks check (look do not touch!) that the seal stays tight and waterproof.
3. Keep the humidity levels above 35 degrees Fahrenheit, not in full sun, with the soil moist not damp.
4. Make sure to not let the soil get too wet or dry out over the summer months, keep the plant in the same pot until fall planting in the ground after temperatures drop below 80 degrees Fahrenheit around mid-October.
5. When planting, leave the grafted union at 2-4 inches above the top of the soil so it doesn’t get crown rot.
6. Water at least two times per week during the first summer.
Grafting isn’t always successful due to some failures:
1. Stock and scion not compatible or healthy.
2. Scion placed upside down, injured by the cold, displaced by storm, birds, or other means.
3. Graft union not completely covered with tape/wax, or girded by tape when not removed at proper time.
Remember to experiment with a variety of scions, grafting types, and have fun growing something different this year.
Colleen B. McChesney is a Master Gardener and can be contacted at firstname.lastname@example.org.