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Paris daisies--commonly seen in white, yellow or pink--are among the most popular cut flowers. They can also be grown as short-lived perennials.
Photograph by Shari Kaplan
Letting weeds go to seed is a mistake for gardeners
By Tony Tomeo
Just as garden enthusiasts maintain their own opinions of favorite ornamental species, they all have different ideas of what the most objectionable weeds are. I could only mention a few of the most common last week. Others include, but are not limited to, spotted spurge, bindweed, nut grass, foxtail grass and blackberry.
Spotted spurge behaves much like portulaca by producing a profusion of seed very quickly. It grows just about anywhere that is exposed, including expansion joints in concrete pavement. It mostly dies back within the next month or so, but can quickly return with warm weather in early spring.
Bindweed resembles and is actually often known as morning glory. It grows in exposed soil, but is more of a problem in dense, hard soil from which the roots are not so easily removed. Those who have them in the garden now have left them too long, because they go to seed in autumn prior to winter dormancy. Not only are seeds profuse, but they may germinate years after the main plant has been removed.
Blackberry is not as common among urban landscapes as the others, but the roots are nearly impossible to kill. One at my mother's home that I started pulling and even dug out a few times since about 1976 is still alive! Blackberry is more common in the north and considered by some as the state weed of Oregon.
Nut grass is also not so common, nor as tolerant to adverse conditions. When it, however, sets seed in well-irrigated areas, it is nearly impossible to eradicate. Foxtail grass is somewhat easier to eradicate than most weeds, unless it gets into lawns. If mowed, it will grow flat along with the lawn grasses and can be difficult to separate.
Unfortunately, space is too limited in this politically correct column for me to adequately discuss herbicides. Selection of herbicides should be determined by the weed to be eradicated. Although some are not specific--killing everything--others are used only for specific weeds. For example, "broadleaf" contact herbicides may be used for dandelions in a lawn of grass. "Contact" and "translocated" herbicides are post-emergent--they're applied to existing weeds. Pre-emergent herbicides kill weeds as they germinate.
Weeds may be pulled from near shallow-rooted plants, but may be tilled or hoed in areas where surface roots are not a concern. Once eradicated, weeds may be more easily controlled if soil is not exposed to sunlight. Weeds do not easily recover if they are shaded by densely planted ornamentals, groundcover or mulch. Of course, it is always advisable to control weeds before they go to seed. They can not easily come back without a new generation.
Flower of the Week: Paris daisy
As long as I can remember, until a few years ago, my mother grew Paris daisies, Chrysanthemum frutescens, which are also known as marguerites. There was always only one plant at a time. Each one would only live for a few years. As they became large, my mother would root a new one over winter to replace the predecessor.
Although they are short-lived perennials, some consider them long-lived annuals. They can grow to 3-feet tall and wide during the first summer and will perform well for about three years unless damaged by frost. They prefer good sun exposure and well-drained soil with regular irrigation. Periodic light pruning will promote bloom.
The bright green, irregularly divided foliage can be "aromatic" when handled, but some find this objectionable. Some cultivars exhibit silvery foliage. Flower size ranges among cultivars from 1 to 3 inches wide, but the large-flowered cultivars that were more popular in the 1970s are now difficult to locate.
Most Paris daisies produce flowers with the familiar single form in white, pink or yellow, all with yellow, composite centers. Cultivars that bloom with double flowers are usually not as well-structured and often exhibit awkward, open growth. The color of the ruffled centers resembles that of the outer petals. (Composite flowers are actually a dense composition of many very small flowers, known as "discs," surrounded by larger, sterile flowers known as "rays." Outer "petals" of daisies are actually rays.)
Paris daisies bloom late into autumn and are most noticeable about now, but should actually be installed later in spring to avoid the necessity of frost protection through unseasonably cold winters when they are not actively growing anyway.
Horticulturist Tony Tomeo may be contacted at 408.358.2574 or at LGHORTICULTURE@aol.com.
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Sunnyvale, California Since 1994
