Rootstocks are important in increasing productivity and improve efficiency through improved tree survival, controlled tree vigour, increased fruit size, yield and quality. Rootstock selection can have a significant impact on the success of the orchard, and can help growers overcome challenges such as heavy soils, fungal pathogens, parasitic nematodes, and cold injury.

While dwarfing rootstocks have been used extensively in the apple industry, these rootstocks have not been as attractive to the peach industry. There are several reasons for this. Peaches bear fruit on one year old wood, so there is a need for new growth on trees. While growers like smaller trees, in the past semi-dwarf peach trees have had issues with reduced growth, lower yields and smaller fruit. More recently progress is being made towards developing smaller trees that do not have these issues.

Currently in the United States growers have seven seedling rootstocks available - Lovell, Halford, Bailey, Tennessee Natural, Guardian, Nemaguard, and Nemared. Clonal rootstocks for peach growers in the US include the Controller series, Viking, Atlas, Cornerstone, Brights Hybrids, Sharpe, and MP-29. Many of these rootstocks are not used in Ontario conditions partly due to issues cold hardiness. There are currently two rootstocks commercially available to Ontario growers, with a third rootstock expected to be available in 2014.

Bailey

An old peach cultivar released from West Branch, Iowa. For several decades this rootstock has been the most predominant rootstock used in the Ontario peach fruit industry. The Bailey rootstock is very a reliable, cold hardy rootstock that produces uniform trees that are medium to large in size with reliable yields and good yield efficiency. It is compatible with most of the scion cultivars grown Ontario.

Krymsk 86

A relatively new peach-plum hybrid rootstock (Prunus persica x P. cerasifera) that originated in the Krasnodar region of Russia. When grafted to peach, plum, or apricot it is thought to be tolerant of cold temperatures, drought, and excessive moisture. It is also considered to be resistant to phytophthora, and somewhat resistant to lesion nematodes. Research is being conducted to obtain more information on the fit of this new rootstock in Ontario's tender fruit industry.

Krymsk 1

This rootstock is not commercially available in Ontario, but will be soon. It is a cross between (Chinese Bush Cherry x Myrobalan Plum). This rootstock is considered to be a dwarfing rootstock and is proposed to control vigour and improve fruit size. Preliminary research in other regions with peaches and nectarines have reported 50 to 60 % the vigour of peach seedling with enhanced fruit size. Incompatibility is an issue with some peaches and nectarines. More research needs to be conducted to obtain more information on the fit of this new rootstock in Ontario's tender fruit industry.