Roses are one of the most popular and versatile flowering shrubs grown throughout South Carolina. Most roses require a lot of care to grow and bloom properly. One of the most common causes of failure with roses is poor disease control. The three most serious diseases of roses in South Carolina are black spot, powdery mildew, and stem canker and dieback.

Remember that different types of roses vary greatly in their resistance to diseases and the maintenance they require. To grow roses successfully, you must select varieties that require an amount of care equal to that which you are able to provide. Shrub type roses bloom beautifully with few chemical controls needed, while the more susceptible varieties such as hybrid teas, require an effective spray program to be in place before the growing season begins.

BLACK SPOT

Black spot is a common and serious rose disease often reaching epidemic proportions in a season. The disease is caused by the fungus, Diplocarpon rosae. It is most severe after long wet, warm periods in the spring. Symptoms occur on rose leaves as circular, black spots surrounded by a yellow area. Infected leaves often drop from the plant. Infection continues throughout the summer months. The immature wood of first year canes develops raised, purple-red irregular blotches. Plants become stunted and produce fewer, paler flowers. By mid-summer severely infected plants may have lost all of their leaves.

Prevention and Treatment: The spread of black spot can be reduced and future infections minimized by following these cultural practices:
• Plant resistant varieties: Roses that have some degree of resistance to black spot and powdery mildew are listed in Table 1.
• Maintain good sanitation: Sanitation practices are critical in reducing future disease development. In the fall remove all old leaves on the ground, and any mulch that has been contaminated with infected leaves.
• Remove and destroy infected canes: Canes affected by black spot have dark or reddish areas (lesions). Severely infected plants should be pruned back in the fall or early spring to within 1 to 2 inches of the bud union, according to variety and cultivar. During the growing season, remove infected leaves as they appear.
• Keep leaves dry: It is best not to syringe plants with water, and do not use overhead irrigation. Promote rapid drying of leaves by planting roses in the full sun, and spacing new plantings far enough apart to allow for good air circulation

Use fungicide sprays to control black spot effectively, even on resistant varieties. A rigorous fungicide program must be followed during conditions that favor disease development for susceptible cultivars. Select one of the following fungicide sprays, if disease is severe enough to warrant control: captan, chlorothalonil, copper hydroxide, copper sulfate pentahydrate, ferbam, mancozeb, propiconazole, triforine or triforine + acephate & hexakis. Apply all chemicals according to directions on the label.

POWDERY MILDEW

Powdery mildew is another widespread and serious disease problem of roses. It is caused by the fungus, Sphaerotheca pannosa var. rosae and produces a grayish-white powdery substance on the surfaces of young leaves, shoots and buds. Infected leaves may be distorted, and some leaf drop may occur. Flower buds may fail to open, and those that do may produce poor-quality flowers. It can occur almost anytime during the growing season when temperatures are mild (70 to 80 °F), and the relative humidity is high at night and low during the day. It is most severe in shady areas and during cooler periods.

Prevention and Treatment: Rose varieties differ in their susceptibility to powdery mildew, thus resistant varieties are the best defense against this disease see . A film of water inhibits infection, so in years when rainfall is high during spring and summer, control measures may not be needed until the drier months of late summer. Remove and destroy diseased leaves and canes during the growing season. Rake up and destroy leaves under the plant in the fall.
If the disease is severe enough to warrant chemical control, select a fungicide that controls both black spot and powdery mildew. Fungicide sprays recommended for use in the home garden include: copper hydroxide, copper salts of fatty acids, copper sulfate pentahydrate, propiconazole, thiophanate-methyl, triadimefon, triforine or triforine + acephate & hexakis, sulfur, lime sulfur, or neem oil (clarified hydrophobic extract). Apply all chemicals according to directions on the label.

STEM CANKER AND DIEBACK

Cankers usually appear as dead or discolored areas on rose canes and vary in color from light tan to dark purplish brown. They are caused by various species of fungi, including Botryosphaeria, Leptosphaeria, Coniothyrium and Cryptosporella. These fungi enter healthy canes through wounds caused by winter injury, improper pruning, wind, hail damage, or flower cutting. Cankers can enlarge until they entirely surround the cane, and/or reach the base (crown) of the plant spreading to other canes or killing the plant. They
commonly occur on roses that have been weakened by black spot, poor nutrition or winter injury.
Prevention and Treatment: There are no fungicides specifically available to control stem canker. Keep plants healthy by controlling black spot, powdery mildew and insects. The following cultural methods can help minimize disease development.

• Avoid injury to the plant during transplanting, cultivating, pruning, and flower- cutting: Wounds are a major way the fungus enters the plant.
• Prune properly: To prune an outward facing bud. This will help to avoid too many branches growing into the center of the plant that may cross and rub together.
• Remove and destroy all infected or dead portions of canes immediately: Make all pruning cuts well below the diseased areas, and prune about one-fourth inch above an outward-facing bud node, without cutting the nodal tissue, at a 45-degree angle. Prune live canes in the spring, not fall. Disinfect cutting tools after use on a diseased plant in a solution of 1 part household bleach to 9 parts water.

RUST

Rose rust is a disease caused by the fungi Phragmidium species. It causes orange-colored spots to appear on stems and leaves. When rust is severe, an orange dust-like substance may be present on the plant surface and on the ground below the plant. Rose rust attacks all plant parts except the roots and petals. Severely diseased leaves of highly susceptible cultivars may turn yellow or brown and drop.
Prevention and Treatment: Provide good air circulation. Do not plant roses in crowded areas and prune plants to keep the centers open. Water plants before noon and avoid getting the leaves wet. Remove and destroy diseased leaves and plants. Fungicides containing either ferbam, mancozeb, propiconazole or lime sulfur are recommended for homeowner use. Apply all chemicals according to directions on the label.

BOTRYTIS BLIGHT

Rose flowers and buds are often infected with the gray-brown fuzzy growth of the gray mold fungus Botrytis cinerea. The fungus is most active when temperatures are 62 to 72 °F and conditions are moist. Infected canes have discolored, sunken areas (cankers) and dieback that can extend down the stem from the flowers. Diseased flower petals have small, light-colored spots surrounded by reddish halos, which can quickly expand into large, irregular blotches. Buds fail to open and often droop. Thrips can cause similar damage to half-open buds, so inspect plants carefully.

Prevention and Treatment:

Keeping the area clean is more important than anything else. Collect and discard all fading flower blossoms and leaves. Provide good air circulation, and avoid wetting the leaves when watering. Disease easily develops on canes that have been damaged and canes that are kept too wet by a manure mulch or wet leaves. If chemical control is necessary, fungicides containing captan, chlorothalonil or neem oil (clarified hydrophobic extract) are available for homeowner use. Use neem oil on a trial basis, especially on open blooms and during hot weather. On dormant bushes PCNB or copper sulfate pentahydrate can be used. Apply all chemicals according to directions on the label.

ROSE MOSAIC

The symptoms associated with Rose mosaic virus (RMV) are highly variable. Yellow wavy line patterns, ring spots and mottles in leaves will occur on some varieties of roses sometime during the growing season. In general, symptoms are most evident in the spring. Yellow net and mosaic symptoms on the leaves are also associated with RMV and detract from the overall quality of the plant. Infected plants become weakened and are more sensitive to damage caused by other stresses, such as drought or low temperatures.
Prevention and Treatment: Virus-infected plants cannot be saved. Rose mosaic spreads slowly, if at all, in established rose plantings through root grafts. Infected plants should be removed from highly prized plantings and destroyed. Buy only healthy plants from a reputable dealer; especially avoid purchasing plants showing any mosaic symptoms.

CROWN GALL

This disease is caused by a soil-inhabiting bacterium, Agrobacterium tumefaciens, that infects many ornamentals in the home garden. The symptoms are rounded galls, or swellings, that occur at or just below the soil surface on stems or roots. The galls are light green or nearly white when young. As they age, the galls darken and become woody, ranging in size from small swellings to areas several inches across. The galls disrupt the flow of water and nutrients traveling up from the roots and stems, thus weakening and stunting the top of the plant.
Prevention and Treatment: To prevent crown gall, select disease-free roses. Once a plant is infected, nothing can be done since there are no chemical controls available for crown gall. Avoid injury to the roots and crown of the plant during planting and cultivating because the bacteria enter through fresh wounds. Remove infected plants as soon as galls are observed. If possible, remove and discard the soil from the area where the infected plant was located. Disinfect all cutting and pruning tools that have been used near crown gall. To disinfect tools, dip them for several minutes in a solution of 0.5 percent sodium hypochlorite (household bleach).

You can also read the Care and Handling of cut flowers part II and part I

Mechanical Damage

Avoid bruising and breaking cut flowers which reduces their aesthetic value and, thus, their wholesale/retail value. Pathogens (disease organisms) may gain access through wounded areas and, thus, further decrease their value. Ethylene production and respiration are both natural wound responses. These two reactions greatly accelerate in response to mechanical damage and, thus, shorten postharvest life.

 Diseases

Flowers and foliage packed moist after harvest are very susceptible to a number of disease organisms. Condensation of water on the flowers or foliage encourages diseases. Avoid moving flowers directly from cool to warm rooms which results in water droplets forming. Botrytis (gray mold) is the most common disease wherever excessive moisture occurs.
Although botrytis can be controlled by fungicides, proper environmental management is the best method. Reduce excessive humidity and do not allow water to sit on the flowers and foliage.

Insects

Insect damage is rarely encountered as long as refrigeration is provided. However, insect damage during production reduces quality and provides entry points for diseases. Cut Flower Storage/Display Facilities A number of quality flower coolers are commercially available today. Choose a model that fits your needs and also controls critical environmental factors, mentioned earlier, as closely as possible.
When choosing a cooler look for one that not only will provide proper environmental needs, but also will help market the flowers. In other words, purchase a cooler that is functional and attractive. One major purchase decision is whether to buy an enclosed or open-air flower cooler. An enclosed cooler controls temperature and humidity to near ideal conditions, allowing for prolonged cut flower storage. An open-air cooler will not maintain the favorable conditions as well as an enclosed cooler but is preferred for customer convenience.
Open air coolers tend to be more inviting for customers to visit, and are especially appropriate in businesses with rapid turnover of floral stock. When feasible, choose a triple pane glass or heated glass floral cooler. During hot and humid weather in Oklahoma, condensation can form easily on cool, thin glass, thus blocking  the consumers’ view of flowers. Insulation of three to four inches is also advisable for energy efficient use. Avoid placing the cooler in direct sunlight, for further energy savings.
Newer models control ethylene with filters that can be placed inside. One additional feature to consider is the dual temperature controls, for allowing storage of temperate and tropical flowers at the same time.
Growers/marketers should contact their local cooler manufacturer for assistance in building a cooler. Not only will suppliers be eager to sell parts and offer maintenance, but some can assist with engineering skills and advice in the construction of the cooler.

 I just started a culinary blog.  All recipes are totally FREE! Find information about healthy recipes, cooking recipes, vegetarian recipes, Chinese recipes, and health enhancing diet, eating, low fat cooking, and low cholesterol cooking.

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After we discuss in part I about the temperature, humidity and nutrition, we will discuss now about light and wather.

Light

Light is not as great of concern as other factors mentioned earlier; however, chronic darkness will cause foliar deterioration. Remember, optimum light levels during production are important to ensure high quality cut flowers.

Water

Plant tissue is comprised mainly of water (at least 95%). Water loss in cut flowers can occur rapidly leading to wilting. Maintaining a low temperature helps to reduce water loss and allows easier rehydration after shipping. Try to prevent any wilting, which will shorten vase life. While it is common to handle flowers dry and rehydrate them later, vase life generally suffers.

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    While most cut flowers are currently imported from out-of-state producers, Oklahoma growers can substantially contribute to and profit from the production and marketing of cut flowers. Greenhouse or garden centers could diversify their operations with cut flowers, depending upon proper care of the flowers and establishment of a market. Since Oklahoma is centrally located in the U.S. and has two major airports, increased production of cut flowers could be warranted. Therefore, establishing care and handling guidelines is critical to the success of cut flower production in Oklahoma. Below is basic information which may be useful to growers, wholesalers, retailers, and ultimately the consumers.

Since water quality and growing, harvesting, and storing conditions vary considerably, it is important to first test any changes in procedures on a small scale. Whether a firm is growing or importing cut flowers, periodic tests of the vase life of the flowers should be conducted to assure that vase life is adequate. Flowers may look acceptable, but may not last as long as possible.

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Here you can see a video with the world most weird plants.

Video school about amaryllis flower. Lets find more about amaryllis.

The Los Angeles Flower District is the Los Angeles area’s premiere flower market resource for flower growers, shippers, suppliers, floral wholesalers, distributors, floral designers, event planners and retail florists in the floriculture and horticulture industries. Just a stone’s throw away from downtown Los Angeles, the Flower District and its flower markets and members are convenient to major freeways and only minutes from major cities and commercial centers, facilitating the flow of floral products from field to consumer. read more

Source: www.laflowerdistrict.com

Tags: flowers district, los angeles flowers, flowers market

GAINESVILLE, Fla. — Some new treats are available for the holidays, but don’t look for them in the candy aisle or bakery — try the florist instead.

These indulgences are eye candy, with names like Christmas Cookie, Santa Claus Candy, Peppermint, Champagne and Plum Pudding. The food-themed names belong to several new varieties of poinsettia developed this year.

University of Florida environmental horticulturist James Barrett said companies in California and Germany that developed the roughly two dozen new strains of poinsettias for this year are responsible for naming the new varieties.

“All the Christmas names related to food are fairly interesting and new for poinsettias because we haven’t had those types of names before,” said Barrett, a professor with UF’s Institute of Food and Agricultural Sciences. [ read more ]

Source: http://news.ufl.edu

Around 120 million years ago, when the dinosaurs ruled the land, much of the world was covered by primordial forest, and plant life was rapidly becoming diverse, flowering plants were evolving and one of the first of these was the orchid.

As the world underwent many changes species of both plant and animal life died out or were replaced, but the orchid family expanded, populating every corner of the world except Antarctica, living on trees, rocks, in the ground or under it, tropical rainforest or lush grassland, high mountain or bog, they thrived, nothing seems capable of upsetting their evolutionary process , indeed it is generally accepted that in the world today, there are around 35,000 different species of orchid in existence; many myths abound concerning them, the most common of which is that they are parasitical plants, this is not so, orchids grow on trees - true, but they do not feed from them, they use the host merely as somewhere to be.

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A truly blue rose has been the Holy Grail of rose breeders since 1840, when the horticultural societies of Britain and Belgium offered a prize of 500,000 francs to the first person to produce a blue rose.

Molecular geneticists with Florigene and Suntory achieved the prize that had long eluded conventional rose breeders by combining something old, something new, something borrowed, and something blue. [ read more ]

Source: www.biologynews.net

The sixth China International Garden & Flower Exposition will open on the Zhongzhou Island of Jimei, Xiamen from September 23, 2007 to March 2008. The sixth China International Garden & Flower Exposition will open on the Zhongzhou Island of Jimei, Xiamen from September 23, 2007 to March 2008.

Construction on the venue, the Xiamen International Garden & Flower Expo Park, is close to completion. With an area of 6.76 square kilometers, it is expected to become the world’s largest park on the sea. Altogether 24 cities from abroad and 44 Chinese cities will show their gardens and flowers. [ read more ]

Source: http://www.flowerweb.com

Did you know that the aromatic Lavender flower is also a remedy? What a pity it is less known than other medicinal and useful plants. We’re presenting you some of the most used lavender home made products.

Lavender powder plant

Grind the lavender plant till you’ll obtain a lavender powder then introduce it in a tight closed glass jar. Put the lavender powder jar in a cool dark place. Take one spoon of lavender powder thrice a day, by keeping it under the tongue for 10-15 minutes and then swallow with water. We want to warn you that the lavender powder is kind a bitter in spite of its sweet scent. That’s why it’s preferred the lavender tincture as a treatment. Continue Reading »

Lavender is a real treasure in the kitchen too. Besides its medicinal benefits, Lavender is used as a spice. Lavender spice is a loosing weight natural remedy, by reducing the appetite, because the lavender helps the digestive system. Mix the lavender with thyme in a 1/5 proportion and you’ll obtain a special spice for the most delicious and most refined meals. Continue Reading »