Intro to Rootstocks
In grafting a rootstock refers to a plant, sometimes just a stump, which already has an established, healthy root system onto which a cutting or a bud from another plant is grafted.
The rootstock may be a different species from the scion, but as a rule it should be closely related, for example, many commercial pears are grown on quince rootstock. When it is difficult to match a plant to the soil in a certain field or orchard, growers may graft a scion onto a rootstock that is compatible with the soil.
It may then be convenient to plant a range of ungrafted rootstocks to see which suit the growing conditions best; the fruiting characteristics of the scion may be considered later, once the most successful rootstock has been identified.
Choosing a Variety
For a graft to be successful there must be compatibility between the rootstock and the scion. Different rootstock have different effects on the growth of the scion. Average total tree size, vigor, early bearing, volume of fruit, and soil tolerances are only some of the features of rootstocks. Depending on your soil, environment, and goals different rootstocks may be better suited than others. It is important to choose the right rootstock for you area.
A suckerless Russian apple rootstock that produces a full-size, 25' to 35' tree. Hardy to -50 degrees Fahrenheit. Wide soil adaptability. Produces large yellow edible apples if allowed to fruit.
A very dwarfing apple rootstock similar to EMLA 9 but more hardy. Trees can be maintained at 6 to 10' in height. Requires staking.
Will produce a dwarf tree from 8-14 feet tall. Does well in most soils. It is hardy to -40 deg. F. Produces fruit in 2-3 years. Can be grown free standing but needs staking on windy sites. It doesn't sucker much in the orchard.
This apple rootstock can be maintained at only four to six feet in height. It is well suited for growing in a container or a small yard. Trees grafted on EMLA 27 bear early and heavily. It needs staking. It is hardy to -25 deg. F. This rootstock is patented and it may not be reproduced without permission of the patent holder.
Produces a semi dwarf apple tree from 11-16 feet tall. Trees can begin bearing in 3-4 years. It is hardy to -35 degrees F. and does well on wet soils. Suckers need to be removed each year.
Grows to 35-40% of standard between a BUD 9 and EMLA 26 in size. A Cornel University selection, resistant to collar rot, fireblight and wooly apple aphid. Tolerant of apple replant disease. Zones 4-9.
Good resistance to crown rot and fire blight, this rootstock produces trees about 11-16' tall. It is similar to EMLA 7, but has better anchorage, higher production and fewer burr knots. Stake for the first few years.
Slightly more dwarfing than M9. Resistant to woolly apple aphid, fireblight and crown rot. Induces high productivity. A replacement for M9 in high density plantings. USDA Zones 4-9.
Produces mature tree about 15-20 foot can be smaller on dry sandy soils; larger on fertile soils. Few suckers, wide tolerance of different soils. Early bearing (3-4 years). Staking recommended for first year or two in windy sites. Susceptible to tomato ringspot virus; resistant to wooly apple aphids.
Produces a semi-standard heavy bearing, precocious, well anchored tree about 20 feet tall. This rootstock has fibrous roots and does well in a wide variety of soils. It is hardy to -35° F. It produces burr knots at the base and should be planted almost up to the graft line.
Will produce a semi-dwarf tree maintained from 10 to 15 feet tall. It does very well on wet soils and tolerates a variety of soils. It is compatible as an understock for plums, and some almonds and apricots.
Also known as VVA 1. Plums, apricots, and nectarines grown on this dwarfing rootstock have proven precocious. An excellent choice for home orchardists, the rootstock produces a tree about half the size of standard and it has shown excellent results when grown in heavy soils.
Grows to 85% of standard size but induces early and heavy bearing. Works well for Asian and European pears and is very winter hardy.
A clonal rootstock of Old Home x Farmingdale which produces a full-size pear tree. It is more precocious than seedling, is winter hardy, resistant to fireblight and pear decline. It is also compatible with most varieties. It can be maintained at 15-17'.
A semi-dwarfing pear rootstock. It is 1/2 to 2/3 standard size. Its resistance to fireblight, collar rot, woolly pear aphids and pear decline make this a very healthy stock. Compatible with all Pears.
Quince Province BA 29C
Makes a 10-15' semi-dwarf tree. Compatible with Cydonia Quince and some European pears. It is tolerant of wet soils.