As Plums are so vigorous and naturally grow very large, their size can 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:

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

Marianna Semi Dwarf
- Controls height to approximately 3.5m
- Tolerant of heavy soils
- Shows good disease resistance

St Julian Semi Dwarf
- 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

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