Some flowers like it hot, so time to get planting
Planting flowers in July may be the last thing on your mind, yet this is the precise moment for maximizing the effect of certain bedding plants that bloom abundantly no matter how hot it gets.
At the top of the list of midsummer-tofall bloomers are Profusion and Zahara zinnias. These zinnias grow to a height of 1 1/2 feet and make an excellent annual ground cover for a splashy entryway or to edge a sunny garden bed. You can find them in white, apricot, orange, yellow, cherry red and bicolors. They spread with great alacrity and, within weeks, a single Profusion or Zahara zinnia planted from a 4-inch container will proliferate into a hemisphere 2 feet wide and 1 foot high.
Flowers are about 1 1/2 inches in size, resemble small daisies and are excellent subjects for containers and hanging baskets. Make sure you plant these zinnias by themselves, however, as they will quickly overwhelm and smother any nearby companion plants.
One of the real bonuses of these zinnias is their resistance to powdery mildew, un- like the tall, conventional zinnias. These zinnias are also recommended for their longevity of bloom — flowers keep coming until November — that growers of traditional taller zinnias could only dream about.
If orange is your color of choice and you have decided to plant orange Profusion or Zahara zinnias in a sunny bed, combine them for an orange free-for-all with orange marigolds, yellow-orange Bolivian sunflowers (Tithonia diversifolia), and orange black-eyed Susans (Rudbeckia hirta). Bolivian sunflowers are long-lived perennials that can grow up to 10 feet tall, while black-eyed Susans live for a few years, bloom most of the time and effortlessly reseed themselves as well.
Tuberous begonias are an excellent alternative to the monotony of impatiens in the shady to partially sunny garden bed. Blooming from now until late autumn, the roselike flowers of tuberous begonias are a universally acknowledged delight. The yellow tuberous begonia is especially prized because summer-blooming plants for shade rarely have yellow flowers. Dahlia, whose wide color spectrum matches that of tuberous begonias, is also suitable for summer planting.
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A gardener in Chatsworth wondered in an email why their “zucchini plants look good but the zucchinis whither up at about 3-4 inches.” When zucchini or any other squash does not size properly or falls off on its own, it's due to inadequate growing conditions, the weather or lack of pollination. The intense heat we have recently experienced could have caused your zucchinis to drop. Make sure soil is kept moist to a 4-inch depth.
That said, often early in the season, squash flowers are all male or all female. When flowers are all female, the small fruit that's formed will drop. Also, if too much nitrogen fertilizer is applied, squash or any other vegetable plant will grow lushly but produce nothing but rudimentary fruit, if any.
Summerweight garden fabric, available through gardeners.com, keeps vegetable crops from overheating. Used as a floating row cover, this woven polyester or propylene material is generally employed to keep out insects and birds and protect from the wind. It is also used to protect from frosts since it adds a measure of ambient heat for the benefit of winter-grown vegetables. Most floating row covers would, in fact, cause summer vegetables to overheat, but the greater porosity of fabrics designed for summer use has the opposite effect. Shade netting row cover, also found at garderners.com and blocking 50% of the sun's rays, will extend your season for growing lettuce.
CALIFORNIA NATIVE OF THE WEEK
Belying its delicate features, Baja fairy duster (Calliandra californica) is one of our toughest native plants. It can grow in poorly drained soil and is cold-hardy down to 25 degrees. It will drop its leaves due to extreme winter cold and drought but bounces back. Flowers look like feather dusters, and ferny leaflets are only 1/4 inch long. Baja fairy duster is a robust grower, reaching 6 feet tall and wide. It can serve as a natural barrier due to the spines at the base of its leaves. Given water now and then, it will bloom virtually yearround, although it can survive in the absence of water once it's well-established in the garden. Nate Benesi, who cultivates a waterless garden for the San Gabriel Mountains Regional Conservancy, has a specimen presently covered with flowers that has not been watered in two years.
Squash has both male and female flowers, and the females need to be adequately pollinated for good size fruit to form. Despite the absence of pollination, a fruit may begin to develop on the stem below the female flower but will eventually fall off. And even where some bees are in the vicinity, pollination may not be properly accomplished to where fruit grows to full size. Female flowers tend to grow in the middle of squash plants and display a bulge, the beginning of a fruit, on the stem below each bloom. Male flowers are larger and are on thin stalks all over the plant. Where squash falls off or does not size properly, it is advised to take a small artist's paintbrush and dab pollen from male flowers onto stigmas of female flowers. You can find videos on YouTube that demonstrate how.
Before leaving squash flowers behind, I would be remiss not to mention their culinary attributes. First of all, you can eat squash flowers raw, straight off the plant, and their taste will resemble that of the squashes you aim to produce. You can also add squash flowers to your salad, put them in a quesadilla, sautee them, submerge them in batter and fry them, serve them over pasta, or fill them with cheese and bake them.
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The same reader mentioned above sent a photo of a mint plant with tiny flecks of white on its leaves. The damage shown was caused by thrips, a sucking insect. Although thrips can carry viruses, the yellow striping or mottling observed on the foliage of infected plants is not seen in this case. So what is to be done?
The current thinking as far as garden pests are concerned is to abstain from chemical applications altogether, including organic preparations. Even where a plant is infested with a pest or ravaged by a disease, the prevailing advice is to remove the affected plant parts or even the entire plant rather than start spraying, which could kill beneficial insects along with the pests. A struggling plant may never prosper where it has been planted — due to too much sun or shade, for example — and its failure should be regarded as a learning experience.
One simple household remedy for combating thrips and other insect pests is to mix 2 teaspoons of dish soap in a gallon of water and spray. Make sure to cover the plant completely, including the undersides of the leaves.
In all likelihood, the mint in question will continue to grow without major complications. To err on the side of caution, the affected leaves should be removed. You should also consider whether there is sufficient air circulation around the plant and note if leaf surfaces stay wet. If the mint is being crowded by other plants, if there is too much shade, or if water from overhead irrigation or hosing down remains on the leaves for long, that would make insects pests feel at home.
Finally, the above Chatsworth gardener mentioned that “pillbugs are everywhere, decimating cucumbers and beans.” To trap pillbugs, place watermelon rind slices, fleshy side down, where these terrestrial crustaceans congregate. In the morning, pick up the pillbug-laden rinds and toss them in the trash. You will also want to poke around in the soil where the rinds lay in order to ferret out any pillbugs still in the vicinity.
Today, the trending strategy regarding pest control is entirely preventive. The idea is to introduce a wide variety of plants into the garden that attract beneficial insects, which will take up residence and prey on thrips and other insect pests before they can gain a foothold and cause significant damage. The presence of water, whether in a birdbath or in a few shallow bowls placed in shady spots, also helps attract and keep beneficial insects around.
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Except where vegetables and fruit trees are concerned, take the words “full sun” with a grain of salt when it comes to recommended exposures for plants in Southern California. This is especially true when planting in July, August and September unless you work from home and can water your new garden babies two or three times a day. But even then, I would plant roses, for example, in half-day rather than full-day sun to get the maximum quality blooms from them in summer months. It should be noted that I dwell in the San Fernando Valley and, as we know, our interior or inland valleys can sizzle in the summer. As you get closer to the coast, “full sun” takes on a different meaning and more of those plants recommended for it will do quite nicely growing in it, even in the hottest months of the year.
Made in the shade: If you are considering a garden for partial shade, select from ferns, epiphyllum cactuses, begonias, bergenia, coleus, callas lilies and hydrangeas. Fuchsias are tricky to grow but one of them, the Gartenmeister Bonstadt variety, is highly reliable in partial shade. It grows into an upright bush at least 3feet tall by 3feet wide with fiery orange flowers and purplish burgundy foliage. Once established, it can live for a decade or more and makes an excellent subject for training up a trellis.