Sweetbay Magnolia Sweetbay Magnolias are medium sized evergreen trees that seem to glimmer in the wind due to the whitish-green underside of their leaves. Their cream-colored, lemon-scented flowers, bloom from June through September. Tree specs Size of tree: 40-50 feet tall. Width of tree: 15-25 feet wide. Shape of tree: Columnar, round. Leaf type: Evergreen. Growing conditions Moisture preference: Normal to wet conditions. Sunlight requirements: Full sun, partial sun or partial shade.