Grafting and budding are methods used to propagate plants, especially fruit trees, vegetatively. Growers choose these techniques because the new plants retain all of the desirable characteristics of a parent plants, and growers have the ability to enhance traits like cold hardiness and disease resistance through rootstock selection. However, certain disadvantages accompany these propagation techniques.
Labor and Time Requirements
Grafting and budding can involve a significant amount of time and labour. Often, the grower must collect the scion wood, or a small portion of the parent plant, at a different time from when he prepares the rootstock and performs the union. This delay requires labelling and proper storage under cool, moist conditions so that the wood remains viable yet dormant. The grower must perform the union and then check to ensure success, remove wrapping and regularly prune any growth produced by the rootstock.
Grafting, budding and other vegetative propagation techniques may prove quite difficult for growers with little or no experience. Unions can fail if cut surfaces do not match and fit together well. Scions and rootstock must be well-chosen and properly maintained. Unions must be kept moist and wrapped well enough to limit the possibility of infection.
Few Plants Produced
Whereas many fruit trees and other plants produce massive amounts of seeds that allow a large number of seedlings to be grown over a short period of time, grafting and budding are generally able to produce fewer plants. Usually, a limited number of rootstocks are suitable and can be prepared for grafting at a given time and a limited portion of a parent tree is viable and can be removed for grafting.
Lack of Hybridization
Although a grower usually propagates a tree vegetatively primarily because she desires no genetic variation, this characteristic may be considered a disadvantage. Sexual propagation by seed allows genetic variability, or the production of hybrids. While growers generally do not desire this, it does allow for the appearance of unique characteristics and variations that may prove valuable.
Nursery Versus Field Grafting
Grafting or budding can be performed on young plants still in a nursery or greenhouse or on field stock, which is often older and already established. While grafting in the nursery often involves little distance between plants, a climate that can be manipulated, an ability to graft under adverse weather and less possibility for scion identity confusion, field grafting can involve a significant distance between rootstock and scion, subjection to adverse weather and no control of climate. However, container-grown nursery plants are often more likely to develop problems with fungal diseases, are labour intensive and plants may suffer from restricted root development.