Magnolias are among the most beautiful trees, and the early-flowering kinds are near the top of the list for spring display. The Kobus magnolia is one of the most pleasing, and fortunately it is also one of the hardiest.
This species is native to northern Japan, and its vernacular ‘name Kobushi was used as a source for the scientific name, Magnolia kobus, as well as for the common name we use. The plant was introduced to this country in 1865, when Thomas Hogg, President Lincoln’s representative in Japan, sent seeds home to New York and the progeny was distributed principally by the Parsons nursery at Flushing. Kobus is quite similar to the star magnolia, M. stellata, which was being featured as a novelty at the same time and by the same nursery. The star magnolia, however, is native to the southern portions of the Japanese islands, and in general it is more shrublike in habit.
Flower differences between the two are quite pronounced. Kobus has six to nine obovate petals of traditional magnolia form, while M. stellata has 14 to 20 narrowly oblong or strap-shaped segments which open rather flat into a less formal bloom. Star magnolia is notable for setting buds freely even when quite small, and it must be admitted that Kobus does not have this beguiling habit.
It is a much more rapid grower, however, and soon surpasses the 6- or 7-foot size when flowers are usually produced. It is of particular interest that the hybrid between these two Japanese species, M. loebneri, seems to combine the best traits of both parents. It promises to make a small tree of the more graceful habit of Kobus, and its flowers have ten to twelve, or more, large obovate petals and are larger than those of either parent.
The leaves of Kobus magnolia typically measure from 3 to 5 inches long, but a variety from northern Japan has larger leaves and much sturdier growth. This is variety borealis, Hokkaido magnolia, which was introduced in 1892 by Professor Sargent of the Arnold Arboretum at Boston. Vigorous plants of Hokkaido magnolia frequently grow 3 to 4 feet in one year, and it is not surprising that in its native forests it makes massive, columnar trees 80 feet high. Unfortunately, this variety does not bloom until well grown, and it also takes too much room for inclusion in many gardens.
