Kobus Magnolia

Kobus magnolia is the large, white-flowered species that serves as the backbone of many magnolia hybrid breeding programs, a vigorous tree that grows thirty to forty feet with a spreading, rounded crown and produces lightly fragrant white flowers in early spring before the leaves emerge. Each flower is about five inches across, with six petals and sometimes a faint purple flush at the base. Native to Japan, where it grows as a forest tree in the mountains.

In Western Washington, Kobus magnolia is valued more as a parent of hybrids than as a garden specimen, though the species itself is a handsome, tough tree. The flowers are not as large or as showy as star magnolia or saucer magnolia, but the tree is more vigorous and wind-resistant. It tolerates a range of soils and conditions better than many magnolias. One disease is tracked, no significant pest concerns. The primary consideration is patience: Kobus magnolia is slow to reach flowering maturity from seed, sometimes taking ten to fifteen years. Grafted trees flower much sooner. For a large-scale magnolia that provides spring flowers and genuine toughness, Kobus is the utilitarian choice in the genus.