Definition - What does Grafting mean?
Grafting is horticultural technique that splices the top of one vine onto the roots of another. The purpose of grafting is to combine the desirable characteristics of the top part (the scion) to the sturdier roots of another (the rootstock).
Grafting is used in all forms of agriculture and commercial horticulture. The scion is chosen based on the quality of its stems, roots, flowers and/or fruit; this winemaker wants this part of the plant to dominate the end result. The rootstock (or stock) is selected because its roots are better equipped to deal with the soil or climate and/or is resistant to pests or disease; the winemaker uses this as a foundation for the desired vine - it doesn’t affect the finished product. Most vineyards in the world use grafted vines.
WineFrog explains Grafting
Wines made from grafted vines taste almost exactly like their original counterparts. The difference in is so small it is considered negligible by nearly everyone in the wine world. Climate, soil, variety, vineyard management and winemaking style have a much larger influence on a wine’s final taste profile.
There are several ways a winemaker can graft a vine:
- Field grafting
- Bench grafting
- Top grafting - includes cleft and bud grafting
In the 19th century, the phylloxera was wiping out Old and New World vineyards. Leo Laliman and Gaston Bazille, French wine growers, suggested grafting their vitis vinifera onto the aphid-resistant native North American vines. Grafting was a success and the process was adopted by winegrowers around the world with the exception of Argentina, Chile and the Canary Islands, who weren’t affected by the phylloxera.
Though fighting phylloxera is the most common reason, winemakers could graft their vines to improve the root system or change the variety. The vitis vinifera evolved specifically for European climates, which are typically mild with very little variance in temperature. Most native North American vines are able to withstand cold climate weather, such as a bad frost. Grafting allows a winemaker to use the sturdiness of the North American roots and the familiar flavor profile of the vitis vinifera berries, making it easier to grow vines outside of the wine belt.
"Top grafting" is used by some winemakers to change the variety produced in their vineyard to conform to the current wine trends. When a vineyard has a surplus of a popular variety and that variety loses popularity, the winemakers have to change. They could replant, but that could take up to five years to produce fruit. Replacing the tops of the vines with the popular variety reduces that wait to one year - so they only lose a single season.