“There are no dwarf trees. There are only trees that grow at a slower rate than others of the same species.”- Ken Love
Tucked away in the hillsides of Hōnaunau, HI is the community garden project Ma’Ona. The work of this community garden spills over into the parking lot, where both the vehicles of visitors and piles of mulch are parked. The chalkboard in the outdoor classroom has a to do list and the quote, “A gardener learns more from the things that don’t work than the things that do.”
We gathered under the shade tents on a tropical summer Saturday to learn about grafting from Ken Love and Xavior Chung. On the table were grafting knives, Parafilm, and tissue samples from trees.
Grafting is a plant propagation method that allows for plant tissue from a plant with desirable genetics to be joined with the root stock of another plant.
Chantal Chung, project manager at Ma’Ona, talks story with us and reveals that a group of six moms have worked together to regenerate an old junk yard into this community garden. They cleared about 6 cars from the 5 acre lot. Some of their kids are now becoming exceptional gardeners themselves. Her son, Xavier, later taught the group how propagate by air-layering. Ma’Ona also offers garden plots for free to anyone who wants to grow food.
In this blog I will summarize notes from the workshop for those curious to learn more about grafting and propagation techniques. Ken Love, candidly revealed that grafting is trial and error and that learning is best done by doing. His teacher told him a good grafter becomes one by trying 10,000 times.
A tree is an intelligent collective of 10,000 to 100,000 meristems, each capable of genetic mutation.
A collection of compatible genetic individuals form a tree entity yet each responds differently to energy and stimuli. (1) So, each fruit and flower has localized and unique qualities such as color, flavor and size. By choosing scion from a fruit tree with desirable qualities, you may propagate the plant and may extend the genetics by fusing the scion with a new root stock.
Choose the best Scion
A scion is a sample from a living plant, such as a branch, bud, or young shoot. It is the part of a plant that is used for grafting upon a root-stock plant. A scion sample should come from a healthy and productive plant that has desirable qualities that you wish to encourage in a new propagation.
Choose a scion that is flowing with buds about to burst out.
Choose older growth from a piece that shows signs of new growth.
Wood should be more brown than green.
Scion should be solid, without any hollowness in the center.
Scion should have no signs of bug damage.
Immediately wrap scion in Parafilm.
Photo: a scion from a mature avocado tree wrapped in Parafilm. Parent tree produces exceptionally delicious and large avocado fruit weighing 1kilogram or more. We grafted directly onto a Hass avocado root stock that is rooted under the parent tree. A successful graft can then be dug up and moved. Or left to mature under the parent tree.
Steps of grafting
Cut root stock low to keep tree growth low.
Make a split in the root stock.
Choose and prepare a scion.
Scion should be from a healthy plant with desirable qualities.
Scion sample should be about the same size in diameter as the root stock if you are planning to fuse the two together in a ‘simple’ wedge graft.
Be sure scion exhibits signs of new growth and new buds.
Wrap scion entirely in Parafilm to prevent moisture loss.
Cut a point in the scion graft stock that corresponds to the cut you have made in the root stock. You will cut through the Parafilm. Both cuts should be similar in length and size.
Fit scion in to root stock.
Align the cambium layers of the scion to match that of the root stock on at least one side. Be sure that you have made cambial contact between both the root stalk and the scion and at least one point of convergence.
If the scion dies and the root stock sends out a new shoot, then re-graft a new scion onto the new shoot.
Tightly tape around the point where the scion meets the root stalk. Ken suggests electrical tape for the job. The new plant growth is so strong that it will grow through both the Parafilm and the electrical tape.
See Photo Below: Aaron is pointing to the original scion wrapped in Parafilm. Notice the green new growth above his hand. Below his hand the electrical tape is being outgrown. Trees are form Ken Love's nursery in Kealakekua.
Care for tree after grafting
Keep the tree dry for a week after grafting. Carbohydrates are flowing to strengthen the cambium layer. The stress that the plant is experiencing will promote the growth of new shoots. We loosely covered the grafted scion with plastic bags.
Water the tree at the base for first three years with an irrigation bubbler. This will promote 60-80% more root mass than if you were to water at the drip line of the tree or forego irrigation altogether.
Cut away all branches that sprout from root stock to prevent regrowth of undesirable fruit.
Things to consider/ trade-offs in grafting
No guarantees. You may not be successful in grafting a scion to root-stalk. Try and try again.
Mother nature knows best. A grafted tree will never “be” as a natural tree. The grafter should take care to learn about species compatibility and learn to respect the limits of growth.
Plant disease is transmissible in grafting . Be sure to pair healthy scion with healthy root-stalk.
There are immutable universal laws of ecology. Grafting does not make possible fanciful chimeras such as the banana-kiwi fruit.
Photo below: A successful mystery magical avocado scion grafted to a Hass avocado root stock. See the new bud growth peeking through the Parafilm. The scion comes from a giant, mature avocado tree the produces creamy large fruit that weighs in at about 1kg each.
Mollision, Bill (1988). Permaculture: A designer’s model. Tyalgum, NSW 2484, Australia: Tagari Publications
Garner, R. J. The Grafter's Handbook. University Press, 1979.