Answer: 'Galaxy' has a pyramidal form and the potential to grow 20'-30' high (in about 10 years). You can safely keep it in a container for another year, but due to the fleshy root system and minimal lateral roots (characteristic of all magnolias), you should eventually plant it in the ground. Since you only recently acquired the tree, it shouldn't be necessary to repot it now. Watch it carefully, though - containerized plants can dry out quickly during warm weather. Water as necessary to keep the soil moist but not soggy wet. Magnolias prefer acidic soil amended with plenty of organic matter so be sure to prepare the planting hole well before transplanting into its permanent home in the ground. Spring or fall are good times to plant trees and shrubs.
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