yellow bird of paradise (Caesalpinia gilleseii)

Summer is the season to appreciate the distinctive floral gifts provided by Cassia and Caesalpinia (sez-al-PIN-ee-uh) shrubs. These heat-loving genera are drought-tolerant members of the legume family of plants. They thrive in near-desert conditions and do not require fertilization.
The other day I set eyes on Cassia floribunda for the first time. This heavily blooming shrub grows 6 to 8 feet tall and is covered in summer with five-petaled yellow-orange blooms that attract butterflies. It makes a wonderfully carefree informal hedge.
Cassia didymobotrya is called popcorn plant by some, since a fragrance of buttered popcorn is emitted when you stroke its leaves. Others refer to it as peanut butter Senna (Cassia and Senna are interchangeable genus names) on account of the aroma produced by its flowers.
Gold medallion tree (Cassia leptophylla) has lately been planted as a street tree in various Los Angeles neighborhoods owing to its moderate stature. Its bright yellow flowers are displayed in late spring and early summer, followed by unforgettable, foot-long, dark brown pods. Gold medallion tree makes the list of shade trees suitable for average-sized yards, although it does lose its leaves during the winter.
Q. I recently rediscovered the magnificent poinciana (Caesalpinia gilliesei) at a nursery near me. I lived in Sri Lanka as a child, and they were everywhere. So I just bought my very own poinciana and plan to plant it on my hillside when the weather gets cooler.
There will be plenty of room up there for it to stretch its legs. But, reading about it just now, I am advised not to plant in a high wind area, as the roots are somewhat superficial – I definitely have some serious wind in Sylmar, up near the golf course. Does this put an end to my plans, or can I stabilize the plant in some way?
-Barbara Mah,
foothills of Sylmar
A. The poinciana to which you refer is a large shrub or small tree that grows quickly to a height of 10 feet. Also referred to as yellow bird of paradise bush, it is native to the Amazon rain forest but can also survive on a bare minimum of water.
I once lived in Yerocham, a small town in Israel’s Negev Desert, where the yellow bird of paradise bush was planted around building entrances. It was watered no more than once every other week and flowered for months at a time.
The yellow bird of paradise bush has golden flowers with unusually long, protruding red stamens that impart an avian quality. Being of tropical origin, its roots, as you mention, are shallow and you are correct to be concerned about it blowing away in a heavy wind.
There is still much controversy about staking trees in windy areas and, for that matter, staking trees in general. Some veteran horticulturists and landscapers go so far as to veto all tree staking since staked trees are frequently unable to stand on their own once the stake is removed.
Where wind resistance is a concern, trunk diameter – as long as trees are not rootbound – is the most important criterion to consider when selecting trees at the nursery. The thicker the trunk, the greater the wind resistance. Multi-trunk trees are also more wind-resistant than single-trunk or standard trees. Single-trunk trees in windy areas, even when staked, usually end up permanently bent in the direction of the prevailing wind.
Since it grows quickly and has a shrubby aspect, managing the development of a yellow bird of paradise bush, especially in a windy area, entails annual pruning down to a height of three or four feet. Doing this will encourage bushy, wind-resistant growth.
Q. I came across some society garlic in my garden and don’t know what to do with it. Can it be cooked? Is it any good for the garden?
-Nancy Kowaiter,
Glendale
A. Society garlic gets its name from the fact that you can still circulate in polite society after chewing on it since it does not produce garlic breath. Yet, in cooking, it has a stronger effect than regular garlic so that it should be added when a dish is nearly finished being cooked.
Some people use society garlic leaves as they would garlic chives in soups, salads and omelets. The best advice is to add it to a few dishes and see if you fancy its taste or not.
As a garden selection, society garlic (Tulbaghia violacea) is at the top of the list of so-called bulletproof plants. A bulletproof plant is virtually indestructible. Society garlic, for example, will survive on a bare minimum of summer water. However, it will look much better, even lush, when soaked on an occasional basis.
Ornamentally, society garlic slowly loses its appeal as the summer progresses. Flower stalks wither and leaves turn brown. Rather than pull off individual flower stalks or leaves, wait until winter and then cut the entire plant to ground level. Soon, bright green shoots will begin to emerge as your society garlic takes on a fresh, revivified appearance.
Tip of the Week
The geraniums with the most glamorous flowers are seldom seen in nurseries. They are more often seen in flower shops since they have gained popularity as gift, as opposed to garden, plants. Geranium series such as ‘Orbit’ and ‘Maverick’ produce large spheres of tightly arrayed florets. Although you may not recognize them as geraniums at all, they are hybrid culivars of the common zonal geranium (Pelargonium x hortorum). Despite their scarcity, these geraniums are worthy candidates for perennial flower beds as well as patio planters. Packets of their seeds are available in most nurseries.