By David Walther, Butte County Master Gardener, December 27, 2013
A beautiful way to add color to your garden in winter and early spring is to plant hellebores. These perennials grow low to the ground in clumps usually no more than one- and one-half feet high, with distinctive leathery, dark-green leaves. Their flowers, about two inches across, appear in clusters that either face upwards or droop downwards. Old-fashioned varieties flower in shades of white and green, but newer hybrids broaden the hellebore color spectrum to include shades of pink, purple, yellow, red, gray and black, in single or double forms, and there are even some spotted and striped varieties.
Hellebores like high shade and thrive under deciduous trees in well-drained fertile soil. Good locations include the north or east sides of walls, and underneath high-branching trees. Like many flowering plants that do well in shady conditions, hellebores do need light in order to bloom profusely, so the more sun you can provide them in a shady location, the more flowers you will have. While a daily blast of afternoon sun in late summer and fall may scorch their leaves, they will still bloom beautifully in the spring.
An added bonus is that hellebores are deer-resistant and do not freeze in cold winters.
Happy hellebores will self-sow if their flowers (which are actually sepals, rather than petals) are not cut off after the blooms have faded; seed pods will form, eventually (usually in July) dropping their seeds close by the mother plant, where new baby plants will develop. Because the new plants develop so close to the original plant, it is a good idea to thin the babies out or transplant them.
Fertilize in September, when they are forming the buds for their winter & spring flowers.
Right now, when you are raking up leaves and cleaning up your garden, is a good time to cut off last year’s hellebore leaves (most hybrid hellebores are stemless). If there are no buds showing yet, you can simply grab the leaves by the handful and cut them off. If the plant has started to bud, just cut off last year’s leaves. It is not absolutely necessary to do this, as new leaves will cover the old ones, and the old leaves will eventually turn brown and can be swept away by hand. If you are in doubt, it is safe to cut anything (stems or leaves) that has turned brown. Cutting them off does make yard raking easier, as once the leaves are gone you can rake right over the plant. This gives the garden a cleaner look now and also later, when the new leaves and buds appear and the plant blooms.
If you want a hellebore that blooms a particular color, it is best to buy the plant while it is in flower, so you know you are getting exactly what you want. That plant will always bloom that particular color, but there is no guarantee that its seedlings will follow suit.
While some early-blooming hellebores are already in flower, most will bloom between late January and early April. Look for them at your favorite nursery.
/span>By Brent McGhie, Butte County Master Gardener, December 13, 2013
Peach leaf curl, citrus blast and brown rot of citrus fruit are diseases common in Butte County. Fortunately, all three can be prevented or reduced with fall and winter spraying.
Peach leaf curl is a fungal disease affecting only peaches and nectarines. Its distinctive symptoms include the curling, reddening, and thickening of leaves as they open in the spring. Diseased leaves will die and fall off, but are usually replaced by new, healthy leaves once the weather becomes warmer and drier. Still, if this disease is left untreated, defoliation can lead to sunburned limbs followed by borer attacks. Over several years, affected trees may decline and fruit production can be reduced.
To prevent peach leaf curl, trees must be sprayed with a fungicide after their leaves have dropped and they are dormant. This is usually in late November, or December. If it is a particularly wet winter, a second application of fungicide can be made in early spring, just as buds begin to swell. An easy way to remember is to target spraying for “curly leaf” at Thanksgiving and again at Dr. Martin Luther King’s Birthday. Once peach leaf curl symptoms appear (when trees leaf out in the spring) it’s too late for anything to be done to stop the disease. Spraying after symptoms show up is ineffective and removing diseased leaves or shoots will not remedy the problem.
For the home gardener, there are two treatment options. The most effective is the fungicide chlorothalonil (commercially sold as Daconil, Fung-onil, and Ortho Garden Disease Control, among other brands). However, it must be handled with care because it is listed as a likely carcinogen and can cause skin and eye irritation if handled improperly or if protective clothing and equipment (gloves and goggles) aren’t worn. A somewhat less effective treatment is copper ammonium complex sold as Liqui-Cop (a Monterey Lawn and Garden product), or Kop R Spray Concentrate (a Lilly Miller brand). It can be made more effective by applying it with 1% horticultural spray oil in the spray solution. As is the case with all garden chemicals, be certain to read and follow all cautions and instructions on the label.
If you prefer not to spray, you can avoid leaf curl by planting resistant varieties of peaches and nectarines. Resistant peach varieties include Frost, Indian Free, Muir and Q-1-8. Although the Frost peach variety is very resistant to leaf curl, it must receive fungicide applications in its first two to three years of growth. Kreibich is a nectarine variety that is resistant to leaf curl.
Citrus blast damage
Citrus blast and brown rot are diseases that attack citrus trees. Although citrus blast is caused by a bacterium that attacks leaves and shoots and brown rot is a fungal disease that causes fruit to rot and turn brown, both of these diseases can be controlled by spraying with the same copper ammonium complex used to treat peach leaf curl.
When heavy rain, high winds and low temperatures occur together, conditions are optimal for citrus blast, especially on the windward side of the tree. Leaves affected by this disease have a withered, bleached appearance, as if “blasted” by a blow torch. Diseased leaves and twigs will die and occasionally a larger branch can die back. In most cases, fruit production is reduced and the appearance of the tree is adversely affected.
As with peach leaf curl, once the symptoms of brown rot or citrus blast appear, it’s too late to treat them. Both of these diseases are associated with cool, wet conditions, so the best time to spray is before the winter rains begin if you wish to protect navel organges from brown rot, usually mid-October. A second spraying in mid-December and a third in mid-January has been shown to be effective in reducing the severity of citrus blast. For maximum protection, all parts of the tree should be thoroughly coated. The rough texture of mandarin skins can make it difficult to wash spray residue off of fruit. If this residue is not acceptable, an option is to delay spraying until immediately after fruit has been harvested.
Brown rot damage and droplets of gum (left) and brown rot on peach (right)
/span>By Michelle Ramsey, Butte County Master Gardener, November 15, 2013
It’s hard to believe, but sowbugs and pillbugs are more closely related to lobsters and crayfish than they are to insects. These soil-dwelling crustaceans belong to the Isopoda order. Sowbugs and pillbugs are similar in appearance and their names are sometimes used interchangeably. However, the sowbug has a pair of tail-like appendages which project out from the rear of its body, while the pillbug has no extreme posterior appendages, and can roll up into a tight ball when disturbed. This is why pillbugs are sometimes called “Roly-Poly” bugs.
Both types of bug range from light to dark gray in color and are between one-quarter and one-half-inch long. They are terrestrial crustaceans with a hard shell-like exoskeleton comprised of seven segmented plates. They have three body parts (head, thorax and abdomen), seven pairs of legs and a pair of appendages at the end of their abdomen (called uropods). Their segmented, oval bodies are convex on top but flat underneath. Because they are crustaceans they breathe through plate-like gills located on the underside of the abdomen. These bugs are the only crustaceans that have adapted to living their entire life on land.
Females have marsupial-like pouches on the undersides of their bodies that can hold up to 100 developing eggs. The immature isopod can remain in the pouch for up to 2 months after hatching. Full development to an adult takes about 1 year. During this time, the isopod will molt 4-5 times. Molting occurs in two stages: first the back half of the exoskeleton molts, then, two to three days later, the front half molts. The life span of both pillbugs and sowbugs is about three years.
Sowbugs and pillbugs are most active at night. They spend daylight hours in moist, dark habitats. Because they breathe through gills, they require a very moist environment. That’s why you will find them hidden underneath rocks, in ground litter, or between the edges of moist grass and sidewalk areas during the day. They do not bite, sting or transmit disease. They are harmless to humans.
Sowbugs and pillbugs are omnivores, mainly feeding on dead or decaying plants and animals, and are therefore considered somewhat beneficial in our gardens for their role in overturning soil and producing compost. However, they have been known to feed on tender plant tissue, seedlings, stems and roots of young garden vegetables and other plants.
Sowbugs and pillbugs are not normally pests. However, if control is required, minimize moisture, clean up debris and decaying matter, and water early in the day so the soil dries out by evening. No moisture - No problem!
For more information, visit: http://www.ipm.ucdavis.edu/PMG/GARDEN/FRUIT/PESTS/sowbugs.html
/span>By Marian Stevens and Brent McGhie, Master Gardeners, 11-1-13
Splitting of green fruit on citrus trees, especially navel oranges, is a problem that shows up frequently in the Fall months. Changes in climate, mainly variations in temperature and humidity, have more effect on splitting of navel oranges than anything else. (And who would not agree that our weather has been especially variable recently?) As the fruit gains and loses moisture, the rind does not expand as fast as the underlying flesh, and splitting occurs. Most splitting occurs on navel oranges, starting near the stylar (or navel) end of the fruit where the rind is thin and at its weakest point. Valencia oranges can also be susceptible to fruit splitting in some years if environmental conditions are particularly variable. Potassium deficiency can cause rinds to be thinner, which can aggravate the problem. The number of fruits affected varies from year to year, mostly depending upon the weather as the fruit matures.
Although splitting is not known to result from any single factor, moderate cultural practices that avoid extremes in wet-dry soil moisture cycles and in nutrient levels should help to minimize the trouble. To avoid these fluctuations, trees should be irrigated regularly, especially during hot, windy weather. When hot and/or windy weather is anticipated, irrigate before this weather occurs. Continue to irrigate lightly for a few days, and then resume a normal irrigation schedule. For fertilization, instead of applying a single large application of quick-release fertilizer, smaller monthly applications through the Spring (February through May) may keep nutrient levels constant. Timed-release fertilizers are a convenient way of supplying nutrients at an even rate, but they are more expensive.
Although split oranges are edible, they are usually too green to be usable. Damaged fruit should be removed and discarded, since they may harbor fungi, bacteria, insects and other unwanted pests
Do you have a question for the Butte county Master Gardeners? Call our hotline, at 530-538-7201.
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By Carolyn Faulkner, Butte County Master Gardener, October 18, 2013
For many gardeners, fall brings with it the excitement of selecting and planting spring-flowering bulbs.
The term “bulb” is commonly used to describe a wide range of plants that have underground structures in which they store their nutrient reserves. These reserves allow bulbs to survive and bloom from year to year, if conditions are right. Knowing the differences among the five bulb types can help you determine when and where to plant them.
Of the five bulb types, the most common are the true bulbs. The best example of a true bulb is the onion. The rings you see when you slice an onion in half are actually leaves modified to hold food for the bulb when it is dormant. Garlic too is a true bulb. Common flowering true bulbs include tulips, daffodils, hyacinths, amaryllis, lilies, and Dutch iris.
The third type of bulb is the rhizome. These have elongated underground stems which sometimes emerge above the soil surface. Some of these stems are thick, while others are the thickness of a blade of grass, but all produce leaf growth from the top, and roots that emerge from the underside. Examples of rhizomatous bulbs are bearded iris, cannas and calla lilies. The cattail is a rhizome. Unfortunately Bermuda grass and mint are also rhizomes, and their small underground stems allow them to spread easily and become invasive.
The fourth type of bulb is the tuber. Tubers are also underground stems, but not the base of the stem as in a corm. Tubers have multiple “eyes” (buds) and most of them prefer filtered sun. The potato and yam are tubers. Begonias, cyclamen and anemones are all examples of flowering tubers.
The fifth type of bulb is the tuberous root. These are roots that form around a central stem. The sweet potato is a tuberous root which is where it differs from the yam. Some examples of flowering plants that have tuberous roots are dahlias, agapanthus and day lilies.
The depth that each bulb is planted varies according to the type: some (like rhizomatous bearded iris) can be planted just below the surface, while others (like tulips) require deep planting of up to eight inches. Because bulb depth varies so widely, it is important to check sources before planting, but the general rule of thumb for plantingspring bulbsis toplant two to three times as deep as the bulbis tall.
Bulbs to plant in the fall for late winter and spring blooms include tulips, daffodils, crocuses, Dutch iris, and many types of lilies. Bulbs to plant in the late winter and early spring for summer flowers include dahlia, canna, begonia, and gladiolus. Light fertilizer can be applied just as the bulbs begin to grow.
Most bulbs like full sun, but there are some exceptions, such as hyacinthoides (bluebells) and many daffodils, which bloom in early spring before trees leaf out.
Most bulbs are perennials, and many do well in containers. Most bulbs prefer well-drained soil, but exceptions include the Summer Snowflake (Leucojum), Camassia quamash, and Lilium lancifolium (the orange tiger lily), cattail and (of course) the Water Lily, all of which like damp, even soggy, conditions.
Once bulbs have bloomed, do not cut back their leaves until they have turned yellow and are obviously dead. The bulbs require these leaves to manufacture carbohydrates and store energy for the next year, through photosynthesis. However, the flower stalks can be cut back to where the foliage begins. It is important to apply a complete fertilizer after bloom in the spring, spreading around the base of the leaves, and to continue minimal watering. Once leaves have been removed the bulb can be dug up and stored in a dark dry cool place or simply left in the ground. Be careful not to over-water. Unless your bulbs are among the water-tolerating exceptions, too much water will cause the bulbs to mildew or rot.
A helpful chart for bulb planting can be found at http://ucanr.edu/sites/sacmg/Sacramento_Bulb_Planting_Schedule/. Keep in mind, however, that our Butte County winters tend to be colder than those in Sacramento.
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