Blossoms: The tree typically blooms in May through June and may occasionally send out random blossoms during the summer months. Because it blooms later in the spring, it is a good alternative to earlier blooming star and saucer magnolias, which are subject to damaging spring frosts. The creamy white flowers are similar to those of the Southern magnolia but much smaller, measuring approximately two to three inches in width. The blossoms are cup shaped and have 9 to 12 petals. Each blossom opens in the morning, closes at night, and lasts for two or three days. Although sweetbay magnolias will thrive in partial shade, they prefer a minimum of four hours of direct sun per day in order to produce their best flowers.