Rootstocks

Plums are so vigorous and naturally grow very large, their size can be controlled by the type of rootstock that they are budded or grafted on to. As with Apples the rootstock will dictate the eventual size of your Plum tree and how it responds to various growing conditions. The rootstocks are a specially selected form of Plum from the same family (Prunus). They form the roots of the tree and the first part of the stem - the scion which is the named variety of Plum is then budded on to the rootstock and this forms the main part of the tree. The most common Plum rootstocks are as follows:

MB Myrobalan
- Controls height to approximately 4-5m
- Tolerant of wet and heavy soils
- Keeps tree size and crop size uniform
- Shows good disease resistance
- Adaptable and hardy

SJ St Julian Semi Dwarf  (often interstem grafted denoted as SJI)
- Controls height to 4-5m
- Good for colder areas or inconsistent climatic conditions
- Bears fruit after 3-4 years
- Can stand on its own roots - no staking

PD PixieDwarf 
- Control height to 3m
- Prolific and will produce fruit after 2 years - fruit will be slightly smaller
- Needs staking
- Likes ideal conditions i.e. sun, good drainage

Peaches & Nectarines

Golden Queen (GQ) Suited to a wide variety of soils, but prefers well drained soils. Drought tolerant. Self supporting. Standard rootstock for New Zealand for many years.  Proven and known performance, consistent.

Choosing Apple Rootstocks

Apple trees are grafted because they do not root well from cuttings and they cannot be grown from seed as true varieties. Those which can be grown from cuttings tend to become very large trees. Grafting on to different rootstocks can control vigour, so that apples can be grown as bushes, cordons, fans and espaliers, as well as standards. Using dwarf rootstocks allows several trees to be grown in the same area as a large one, and the dwarfer rootstocks tend to bear fruit earlier. This is important for those who are impatient or who have limited space. The rootstocks we use, from the dwarfest to the most vigorous, are;

M27 The most dwarfed, for bushes, espaliers, fans and cordons. Needs staking. Height usually to 2.5m 

M26 Dwarfing. Good for large bushes, cordons, espaliers or compact standards. Height up to 3m

MM106 Semi-dwarfing. Good for large bushes, large cordon and espalier or half-standards. Up to 4.5m

MM793 Minimal dwarfing.  Good for replanting sites and clay soils. Plants grow to 4-6m

The most dwarfing rootstocks will start bearing fruit after 2-3 years and after 4-5 years will have a good crop. The vigorous rootstocks take longer to reach capacity, though they will bear crops along the way. The more vigorous the rootstock, the greater the yield, but the higher you have to go to pick. When choosing the rootstock, it is worth bearing a few other points in mind. The rootstock does control growth, but some varieties will still be more vigorous than others. The vigour of the variety can be traded against the vigour of the rootstock. The shape of the tree will also vary; some are more upright, others more spreading. Trees and fruit also vary with the soil. Rich loam will always make apple trees - or any trees - grow faster than heavy clay. The ideal soil for growing apples is neutral or slightly acid, with reasonably-drained loam at least 600cm deep. In practice, this is not always possible and they will grow reasonably well in heavy soil, with lime and less depth, though it is a good idea to condition the soil by digging in quantities of organic matter. (In moderation and not fresh manure). If the soil is poor, it is best to avoid the dwarfest rootstock, M27, as it tends to be shallow rooting, and a more vigorous rootstock will be 'dwarfed ' anyway by the poorer soil.

Apples as a rule the lower the number the smaller the plant

M27 Extremely dwarfed, Plants reach 1.2-1.8m x 1.5m Produces a tree 15-20% of the size of seedling rootstock.  Small fruit size.  Medium tolerance to Phytophthora, susceptible to woolly apple aphid. Support required.

M9 dwarfing, Plants reach 1.8-2.4m x 2.7m Produces a tree 25-30% of the size of seedling rootstock.  Tolerates Variable and heavy soil conditions, resistant to Phytophithora, susceptible to wooly apple aphid, fireblight and mildew.  Support required for anchoring.

MM102 Semi Dwarfing Small Plants reach 2.7 - 3m x 1.8 - 2.4m Produces a tree 50-55% of the size of seedling rootstock.  Better for replant sites and wet soils than MM106, resistant to woolly apple aphid, Grows trees with low branch angle.  Can be freestanding but support suggested.

MM116 10% smaller that MM106 Plants reach 3.30 - 350m x 300m Similar vigour to MM106 - Produces a tree about 65% the size of seedling rootstock.  High resistance to collar rot and woolly apple aphid.  Good for semi intensive planting or replant sites.  Support when young.

MM106 Semi-dwarfing, Medium, Plants reach 3-4m x 4m also gives tolerance of wide range of soils but not heavy clay, doesn't sucker, resistant to woolly aphids, heavy cropping, moderate vigour. Susceptible to Phytophthora.  Support suggested when young.

M793 Large Plants reach 4-6m resistance to woolly aphids, adaptive to wide range of soil types.  Produces a tree about 85% of the size of seedling rootstock, about 30% larger than MM106.  Resistant to collar rot and woolly apple aphid, good tolerance to Phytophthora.  Intermediate susceptibility to fire blight.  Suitable for replant sites and clay soil.  Less productive that MM106 Support when young.

Pears & Quinces

QN Quince

QuA Quince A semi dwarf, semi vigorous 3-4.5 m 

QuC Quince C dwarfing Plants reach 2.5 - 3m, produces a tree about 50% of the size of seedling stock.  Used for high density planting, Resistant to pear decline, crown gall, mildew, nematodes and root aphids, susceptible to fire blight. Less resistant to wet soil conditions than QuA or BA29.  Support required.  Interstemmed with DDC

BA29 Pear semi dwarf produces a tree approx. 80% of usual size of seedling rootstock, high yield, drought tolerant.  Resistant to pear decline, crown gall, nematodes and root aphids, susceptible to fire blight. Usually interstemmed with DDC.

PC Pyrus Calleryana Commercial trees are able to fruit earlier in their life cycle when grafted to PC, plants are still vigorous and precocious

CM Pyrus Communis, non dwarfing, vigorous, fireblight resistant.

Citrus

TF Trifoliata

FD Flying dragon (Reduces citrus size by approx. 1/3) Dwarfs

Avacado

ZU Zutano

Cherry

CT Colt - Vigorous rootstock that grows to 5-6 metres. Good for difficult soil, resists crown gall, cherry replant disease and bacterial canker.

EZ Edabriz - A dwarfing rootstock, tree grows to approximately 2-3 metres.

EZI Edabriz interstem - Colt roots grafted with Edabriz on top, then grafted with the chosen variety. This way if you have difficult soil but still want a dwarf tree you can have the best of both worlds. Due to the Colt roots, vigour is a little higher than straight Edabriz.  Tree grows to approximately 3-4 metres.

Walnuts

JR  Juglans Regia

Crabapple

MM102

Prunus

SI Serrula on Interstem 

Grapes