The Malus domestica M9 rootstock is the most planted rootstock and commonly used rootstock in high density fruit production worldwide. The best known type of the M9 is the T337 (M9 T337) selection.

The majority of the rootstock production from Fruit tree nursery J. Morren are represented by the M9T337 rootstocks. Also most of the trees grown in the nursery, are made on M9 T337 rootstocks. The M9 is available as one year old rootstock, from own stoolbed (mother garden), and as two year old rootstock.

The M9 T337 rootstock is weak to moderate vigorous. The malus M9 are widely used rootstocks for high density orchards on fertile grounds.

Trees grown on this very important dwarf apple rootstock are relatively small in height. A support system, stakes, are required. First apple production from fruit trees on M9 can be expected in the second year after planting.

The rootstocks are usually graded in size categories (in mm) 4/6, 6/8, 8/10, 10/12 and 12+. On client request we can do specific grading, for example 8/12.