On the east side of Hazeltine Avenue, just north of Riverside Drive in Sherman Oaks, I was compelled to stop my car and photograph a Chitalpa tashkentensis tree. Chitalpa is a hybrid between Catalpa speciosa — a tree I wrote about not long ago that grows well in Southern California despite being native to the Mississippi Valley — and Chitalpa linearis, commonly known as desert willow.
Both of these parent trees are in the trumpet creeper family (Bignoniaceae), a botanical clan that includes jacaranda trees and every sort of trumpet vine. Desert willow is native to the American Southwest, with a habitat that stretches all the way to Kansas. California desert willows have flowers that are white to pale pink while, as you go east, naturally occurring desert willows have flowers with increasingly burgundy and purplish coloration.
Desert willow is hailed for its medicinal qualities among the indigenous tribes of the Southwest. It is especially touted as a cure for fungus diseases of every sort, from toenail to yeast infections. The Sherman Oaks variety that I observed in bloom is ‘Pink Dawn.’ It produces a spherical canopy that is 15 to 25 feet in diameter and blooms from spring until fall.Silk tree (Albizia julibrissin) is native to the dry climate of Southwest Asia. Its species name, julibrissin, means “silk flower” in Persian. Flowers are reddish pink puffs and foliage is of a bipinnate, feathery sort common to many leguminous trees. Leguminous trees are kin to more familiar legumes common such as peas, beans and alfalfa. As members of the legume family, silk trees are well-suited to arid zones with infertile soil since they possess root nodules inhabited by bacteria that turn atmospheric nitrogen into nitrate fertilizer. Thus, you frequently see lush leguminous trees growing in desert landscapes where water is scarce and fertilizer is never applied.
Gold medallion tree (Cassia leptophylla) is another leguminous tree of note. It is presently showing off large inflorescences of golden yellow flowers. These blooms are followed by dark brown, foot-long seed pods. If you wish to propagate the seeds in the pods, you can do so by pouring boiling water over them and allowing them to sit in the water for 24 hours. Plant them out in pots and you should soon have a nice collection of gold medallion seedlings. Incidentally, this method of propagation from seed is effective with nearly all leguminous tree seeds, including silk tree, carob, black locust (Robinia) and acacia.
Plant your flowers now
Now is still a good time to plant a flower garden since June has its fair share of mild days before the full force of summer’s heat is upon us. Long stretches of hot weather, which normally begin in July, are a challenge to newly planted flowers, which resent being taken from pampered growing grounds into the real world of our yards and gardens.
Echinacea or coneflower is a medicinal perennial that is not that widely grown in our area but is worth trying as long as you are OK with its above average water requirement. It requires full sun and is not bothered by frost. It is also a sturdy cut flower, holding its own in vase arrangements for more than a week.
Pincushion flowers (Scabiosa columbaria) bloom virtually year around. Plants are perennial and flower colors range from pink to lavender to purple. Pincushion flowers grow well with coneflowers, exhibiting a similar water requirement.
Dahlias are among the most dazzling of spring and summer flowers, ranging from 3 to 10 inches in diameter. Their pompon inflorescences appear from now until fall. They need good sun exposure and air circulation to keep their foliage fresh and mildew-free. Plants grow from tubers that can be lifted — when flowers and leaves disappear in the fall — and stored until the following spring in a dry and cool place such as a garage. Several weeks before spring, place tuberous roots in pots filled with sandy soil so they can begin to grow prior to being returned to garden. If tuberous clumps are cut, make sure to dust cut surfaces with sulfur to discourage decay.