freeway daisy (Osteospermum fruticosum)

For years, the dazzling white, trailing African daisy was a staple of highway landscaping, so much so that it earned the sobriquet “freeway daisy.” The plant proved astonishingly tough, and although it developed dead patches often enough, there wasn’t a more stunning ground cover in full bloom.
After a while, you began to see a closely related violet-purple freeway daisy planted for diversity’s sake. It was attractive enough but a far cry from its blindingly white counterpart.
I mention the familiar trailing African daisy (Osteospermum fruticosum) because of its lesser-known cousin, Osteospermum ecklonis `Asti White.’
A mounding hybrid, `Asti White’ has just been named outstanding bedding plant for 2008 by the prestigious All-American Selections organization, a kind of J.D. Power of the horticultural world.
`Asti White’ grows into a symmetrical mound that is 18 inches tall and 18 inches wide and is a superior performer either in garden beds or in containers. It can bloom at any time of the year but does so most heavily from late winter to early summer.
Unlike the freeway daisy, its flowers stay open on overcast days. It can grow in full or partial sun.
South African ground covers and bedding plants, including gazanias, iceplants and geraniums, are most often undermined by overwatering. They come from a climate like our own, which means they must endure a long dry season. Watering should not be indiscriminate but only when the soil is nearly dry.
You may have noticed that when gazanias, iceplants, geraniums or freeway daisies are in need of water, the leaves do not wilt for some time but curl inward. This is evidence of their capacity to endure drought.
In summer, too much water around their roots leads to fungus problems. Hence, dead patches, a result of overwatering, are often associated with plantings of gazanias, iceplants, geraniums and freeway daisies.
Speaking of drought, San Marcos Growers of Santa Barbara has introduced many exciting succulent plants for 2008. Actually, some of these plants were grown by the nursery at one time and are now back by popular demand.
When you think of agaves, you probably conjure up pictures of the century plant (Agave Americana), a forbidding species whose splayed and leathery leaves may exceed 6 feet in length. However, there are many highly aesthetic and eminently manageable agave gems with which you need to be familiar.
The Queen Victoria agave (Agave victoriae-reginae `Compacta’) resembles an imperial crown, a prickly pincushion no more than 1 foot tall, whose circles of concentric green leaves are etched in white along the margins.
The dwarf butterfly agave (Agave isthmensis), with a demure, rosetted growth habit, has the classic powder blue agave color, and it, too, grows no more than 1 foot tall. The similarly dwarfed ivory-
spined agave (Agave utahensis var. eborispina) has leaves tipped in creamy white.
Many agaves are suitable for Antelope Valley gardens, as they survive temperatures of 10 degrees or lower. In addition to the Queen Victoria and ivory-spined agaves, mountain agave (Agave montana `Baccarat’), a symmetrical, 5-foot plant with shark’s-tooth studded foliage, is comfortable in sub-freezing temperatures.
In addition to the agaves, San Marcos is adding other notable and exotic succulents to its list, including aloes, cotyledons, dyckias, echeverias and yuccas. You can learn more by going to www.smgrowers.com.
San Marcos Growers does not sell to the public directly, but the nursery’s plants may be ordered through most Southern California nurseries.
Incidentally, if you acquire succulents at this time of year, you should leave them in their containers until the weather warms. It is not a good idea to plant succulents or cacti during the winter since cold, damp soil will suppress their growth and could even lead to fungus problems.
In fact, nothing should be planted now, since digging in wet earth results in soil compaction, which can keep roots from growing outside of their root balls and into the surrounding soil when temperatures warm.
Tip of the week
The Tarzana Community and Cultural Center, 19130 Ventura Blvd., is creating a unique garden that needs volunteers to assist in its design and care. Anyone interested in helping out should call (818) 705-1286.