February means it’s time to start collecting graftwood!
What is grafting?
Grafting has been around since ancient times. The Chinese practiced the art of grafting as early as 1560 BC according to documents which described in detail the grafting of a pear tree. Aristotle also discussed grafting in his writings around 340 BC and said, “Some trees come into existence by being planted, some from seeds, others spontaneously.”
While this form of plant propagation is considered somewhat expensive, it continues to be highly desired by both landowners and the horticultural public. Many woody plant species are primarily propagated in this way for reasons such as improved plant quality, more impressive fruit and nut development, disease and insect tolerance as well as better adaptation to growing conditions. This propagation method allows a landowner to choose a root system (rootstock) that grows well in their native soil. Then, the landowner can choose a highly desirable variety (the scion or graftwood) of a fruit, nut or flower that does not grow well in their native soil on its own root system. The scion or graftwood (fruit, nut of flower variety that is wanted) can be grafted onto a rootstock or root system that grows well to allow the landowner to enjoy a variety that normally would not do well for them.
Timing is important!
Timing is critical in grafting. The weather is always changing and our seasons typically do not fall on the same day every year as we all know. This also means that our plants will come out of dormancy at different times as well. Mother Nature likes to change the date! However, one grafting duty that is fairly easy to remember is to collect graftwood near Valentine’s Day. You will actually graft the plant a couple of months down the road.
Grafting is the art of joining two pieces of living plant tissue together in such a manner that they will unite and grow. There are all kinds of grafts that can be done. Some of the most common are the four-flap graft (best for beginners) and the inlay graft (very popular with pecan trees). We collect graftwood now because the wood is dormant. New grafts need to be dormant because the connection needs time to grow together before the buds begin to grow. The graft and the rootstock will need to make a “connection” or the graft will die. Timing is critical! We collect the graftwood now and do the graft later to achieve the perfect timing (probably in April or May).
Collect the graftwood in mid-February to early March while the tree is still dormant. If the buds have begun to swell and grow, the wood is inferior and cannot be used successfully. Actual grafting should not be attempted until the sap is moving in the tree (the bark is slipping) and there are small leaves present. This will likely be in early April. The four-flap graft and the inlay graft can both be done through May in most years.
What is graftwood?
Dormant graftwood should be a straight, one-year-old shoot that is 1/4- to 1/2-inch in diameter. In cases where graftwood of a rare variety is needed, two-year-old shoots can be used. Young, fast-growing trees or pruned mature trees make excellent dormant graftwood sources. Do not use drought, freeze-damaged or herbicide-damaged trees for graftwood. Each graft stick should contain at least three buds or nodes and should be cut into 12 or 18-inch lengths.
How do you store graftwood?
The graftwood should be processed the same day it is collected. It is best to only work with one variety at a time to make sure varieties do not get mixed up. The freshly cut ends should be dipped in grafting wax, orange shellac, paraffin or a pruning compound. The graftwood should be kept in bundles of five or six and labeled. Once five or six graftsticks are processed, you will wet a paper towel and wring it out completely, and even wave it around a time or two before wrapping your graftsticks in it. Wrapping graftsticks in a paper towel that is too wet will invite mold! The graft sticks need only a tiny bit of moisture to maintain the proper atmosphere. Once the graftsticks are wrapped in a slightly moist paper towel, they should be placed in a polyethylene bag. The polyethylene bag you choose will need to “breath” to allow carbon dioxide to exit and oxygen to enter. Regular plastic baggies cannot do this and should not be used. A second method involves placing the graft stick bundles in slightly moist sphagnum moss or wood shavings.
Store the graftwood at 35-45 degrees Fahrenheit but watch it carefully and be careful to not let it freeze. Graft sticks can be used for one year only, so label all grafts by variety and year. Throw away all old graftwood before putting new graftwood in the refrigerator. Do not place graftwood in a refrigerator that also has fruit in it, especially apples. Fruits give off ethylene gas as they ripen and can kill your graftwood.
Grafting is steeped in history and a skill that can bring new and improved plants into the landscape. The first step for some of the most popular grafting techniques is to collect graftwood. Graftwood can also be purchased. If collecting graftwood, it is important to collect and process the wood correctly so that grafting in the later spring will be successful.
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Rebecca H. Parker is horticulture manager at Frank Buck Zoo in Gainesville. Reach her at email@example.com or 940-668-4533.