gold medallion tree (Cassia leptophylla)
Q: I’d like to plant a nice green, shady tree, not too tall nor wide. It would have full sun but no sprinklers and you could hang lights on it during holidays. I have done research in a number of books but am still not sure of the right kind of tree to plant. Could you recommend any?
— Barbara Henricks,
Riverside County
A: If I were you, I would first consider the deciduous silk tree (Albizia julibrissin). This native of Asia, growing wild from Iran to Japan, has naturalized throughout the Southeast United States, where it is called mimosa. The silk tree has a vase-shaped form, slightly domed canopy, and generally stays under 30 feet tall. It grows rapidly to its mature height, but remains a medium-size and eminently manageable tree, seldom if ever needing to be pruned. The silk tree yields wispy pink or red flowers in addition to its soft, pinnate and pendulous foliage. It is drought tolerant, can grow in either full sun or light shade, and can survive temperatures down to 5 degrees below zero (Fahrenheit).
A new silk tree variety called `Summer Chocolate’ was discovered growing as a seedling in Japan a number of years ago and has become one of the most sought-after trees among gardeners everywhere. New foliage is bronze-green to maroon, darkening to deep burgundy. `Summer Chocolate’ was patented by Hines Nursery in Irvine, so it should be more available locally than in other parts of the country.
Another species you might try is the gold medallion tree (Cassia leptophylla). A few years ago, the city of Los Angeles began using it as a street tree, a sure sign of its manageability and minimal pruning requirements. Masses of yellow flowers are produced in late spring or early summer, followed by long and sturdy seedpods.
The pagoda tree (Sophora japonica) has panicles of cream-white flowers, but it’s really grown for its highly symmetrical, globe-shaped canopy. It may eventually reach 40 to 50 feet but is a slow grower and will take many years to reach this height.
All three of the above-mentioned trees are legumes and are easily propagated from seeds. Once pods have ripened, remove the seeds and drop them into water that has just boiled. Keep seeds in water for 24 hours and then plant in any sandy or other fast-draining soil. Germination of some of the seeds should occur within three weeks. To increase the germination percentage of leguminous tree seeds, rub them between two pieces of sand paper before giving them the boiling-water treatment.
TIP OF THE WEEK: Robert West, who lives in Palmdale, responded to last week’s column on Dutch bulbs with the following e-mail: “I was lucky enough to be stationed in Holland for 2 1/2 years with the U.S. Air Force. When the bulbs were in bloom, it seemed as though the whole country had this beautiful smell of flowers. I learned that freesias are especially fragrant. In my own bulb-growing experience, I have learned that if bulbs are kept in the refrigerator with apples, there is a gas given off by apples (ethylene) that will kill the bulbs. Another fact I have learned is that in very warm summer areas, like up here in Palmdale, bulbs must be kept cool in the summer or they will bake. I recommend planting them in containers — as opposed to the ground — and moving them to a cool place after the leaves have turned brown.
