When jacarandas bloom, you know summer is here.
Although summer officially begins later this month, the jacarandas have been blooming since early May, about the same time the Valley summer – which usually lasts until mid-October – makes its unofficial debut.
Jacaranda is a Portuguese name given to a magnificent sub-tropical tree (Jacaranda mimosifolia), with lavender blue trumpet flowers, which is native to Brazil, Peru and Argentina. Pronounced “hacaranda” in Brazil, it is also known as blue haze tree on account of its flowers, which are actually more mauve than blue but do produce a hazy glow when viewed from a distance.
The jacaranda is known as a semi-deciduous or semi-evergreen tree. What this means is that it undergoes a period of defoliation at winter’s end; the more tropical the climate in which it grows, the shorter its period of leaflessness. The jacaranda’s flowering is that much more memorable when it precedes the appearance of foliage, a tendency most pronounced after a dry winter.
Given full sun and plenty of room, jacaranda trees are easy to grow and, even at their mature height of 50 or 60 feet, less demanding in terms of maintenance than other large trees. They are virtually pest free, should not be heavily pruned, and are frost sensitive.
Jacaranda wood is somewhat brittle and branches will snap in heavy winds. For this reason, jacarandas should not be planted within 30 feet of houses or other structures.
In general, trees are planted much too close to buildings in Los Angeles. This results in accumulation of leaves on roofs, not only clogging rain gutters but destroying roof shingles as well. If shingles are not regularly swept clean, acid released by decomposing leaves will eat away at the shingles. Roots of large trees will also grow into sewage and irrigation lines.
The one complaint commonly registered against jacaranda trees involves the stickiness of their flowers. These flowers will stick to the bottom of your shoes and eventually show up on the living room carpet. Also, parking under blooming jacarandas will cause sticky windshields and stained car paint. Still, such inconveniences are a price worth paying for the unsurpassed beauty of this tree, which is especially evident when it is planted as a colonnade on both sides of a street, as can be seen on Stansbury Avenue, south of Ventura Boulevard, in Sherman Oaks.
Aside from blooming jacaranda trees, perhaps the most reliable harbinger of summer is the appearance of annual vinca (Catharanthus roseus) in nurseries. No summer annual is more delightful than this. Its pinwheel flowers are lavender, mauve, rose-purple, salmon, pink, or white. The foliage of vinca is truly special, of a deep and lustrous green that stands in sharp contrast to the dull foliage of nearly all other annuals.
In truth, vinca is a perennial that can live up to three years if it is properly maintained. More often than not, however, it is lucky to make it through a single Valley summer and is therefore treated as an annual. In dry climates like ours, the primary cause of vinca’s downfall is disease. It is susceptible to four different fungus diseases and one virus.
To prevent fungus problems, plant vinca in well-drained soil. When you water, soak the soil well and then let it go bone dry before the next watering; avoid daily sprinkler irrigation.
One way to prevent spread of fungus in a vinca planting is to use a good mulch such as shredded bark or pea gravel. Fungal spores on the soil surface will be covered by the mulch and not be splashed up onto the plants during watering.
< GARDEN WONDERS Gardener: Herman Ackley Residence: North Hollywood Plant of interest: Madagascar palms What makes this plant amazing: About 15 years ago, Ackley planted two small Madagascar palms in redwood pots, not knowing if the plants would survive the winter. Not only did they survive, they have since grown to be about 8 feet tall. Three years ago, they put out white flowers with yellow centers, which Ackley describes as ``a mass with eight or 10 soft flowers in a circle, single-petaled and kind of soft.'' And this year, for the first time, the palms have grown hard green banana-shaped pods that sit parallel to each other, facing away from the plant with a single seam in each. ``I've gone to several nurseries and they've never heard of them blooming like that out here,'' Ackley says. How it's maintained: ``All I do is water them and give them a little fertilizer occasionally. They require very little care.'' What Joshua Siskin says: ``It's not a palm at all - it's a succulent plant. It's closer to a cactus than a palm. The pods are just this particular plant's fruiting structure. ``These plants' flowers are seldom seen, so the man is very lucky. It proves you can create the perfect micro-climate if you're lucky, and if you spend the time investigating the circumstances.'' - Mike Chmielecki