Answer: LEONARD MESSEL MAGNOLIA (Magnolia x loebneri 'Leonard Messel') will grow either as a shrub or as a tree. In full sun, pruned as a shrub, it will grow to 10 to 15 feet high, 12 feet wide; as a tree, it will grow to 20 feet high, 25 feet wide.
The roots of magnolias are relatively close to the surface, and you can expect them to travel out one and one-half times the diameter of the canopy. As a shrub, the roots will grow out at least 12'; as a tree, expect to find roots at least 25' from the trunk.
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