Not coincidently, most nitrate-based fertilizers designed for vinca are also low in phosphorus. Most importantly, be absolutely sure to promote good root development prior to use of any PGR on vinca. and replaced every year, even in those zones. Flowers on infected plants are usually discolored and malformed. Bobs Market & Greenhouses, Inc. | 1334 Second Street | Mason, WV 25260 | 800-447-3760, Bob's Market & Greenhouses, Inc. - Corporate Office. 1996. Often there is a purple to black discoloration in a V-shaped pattern spreading from the petiole up the main leaf vein. Users agree that automated translations may not effectively convert the intended design, meaning, and/or context of the website, may not translate images or PDF content, and may not take into account regional language differences. Water every other week, or if the top 2 inches of soil feel dry to the touch. Vincas are heat and drought tolerant, so less water will be needed as the weather cools off in the fall. Transplanting immediately into warm soils with a high level of substrate charge (fertilizer added by the manufacturer) on a sunny day doubles the stress on the roots. Fungicides can reduce infection of new leaves, but they will not cure already infected leaves. At least four HAF fans should be running in a 30' x 100' greenhouse. Vinca, In: G.A. Mix a 1-inch layer of compost into the top 6 inches of soil before planting vinca in the garden. them in for the winter, be sure to move the plants indoors when night Maximize your customer's success by planning ahead and providing containers that drain rapidly. 3Forrest Stegelin is an Associate Professor of Agricultural Economy at The University of Georgia, Department of Ag Economics 315 Connor Hall, Athens, GA 30602.4Bodie Pennisi is an Assistant Professor of Floriculture and Extension Floriculture Specialist at The University of Georgia, Rural Development Center, Tifton, GA 31794. Of two water sources, one with a pH of 9.0 and alkalinity of 50 (calcium carbonate equivalent), and the other with a pH of 7.0 and alkalinity of 300, the first will raise substrate pH very little, while the second will cause a much higher rise in the substrate pH. You can then suspend the planter on gravel within another decorative tray if necessary. Supplemental lighting up to a total of 18 hour days, at 1200 to 1500 foot candles (fc), is optimal, but any supplemental light above 200 fc will help. Suggested production schedules for Vinca. Roots can be off-color, stunted and stubby. Always examine plugs carefully for symptoms of infection such as uneven growth and poor foliage color before introducing them into production areas. When Check the plant's leaves for aphids or mites when you water the plant. and fall, usually as rooted cuttings in flats. Plant 12 inches apart, feed Venting early in the day when moisture has condensed and before the air is warmed can reduce humidity in warmer months. Make sure that the soil is allowed to dry between waterings. Sometimes under warm and humid conditions, the thread-like hyphae of Rhizoctonia can be seen suspended between the stems and lower leaves. Phytophthora aerial blight caused by the fungus Phytophthora parasitica is a common and extremely destructive disease on annual vinca, predominantly in the landscape, however, it does occur in greenhouse production. Roots infected with Pythium appear tan to brown and water-soaked or slimy. Iron-EDDHA seems not to cause the same root stunting problems. Vinca requires long periods of high light levels and warm growing conditions to produce strong roots. This yellowing pattern is very distinct, with very strong veinal chlorosis; specifically, the veins turn bright yellow and the leaf space between the leaves remains green. Avoid watering from overhead, so that the foliage and flowers do not get wet. Apply to the product label to determine the form of chelating agent. It is hardy in USDA Zones 4 through 10. Remove dead or dying tissues from plants and the soil surface, as well as any dead or dying plants. overwatered. Water when the soil is dry to the touch 2 inches down. Vinca (Catharanthus roseus, Family Apocynaceae) is one of the top-10 best selling bedding plants in the United States. 1Paul A. Thomas is an Associate Professor of Floriculture and Extension Floriculture Specialist at The University of Georgia, Department of Horticulture, 215 Hoke Smith Building, Athens, GA 30602. In general, root diseases can be minimized by avoiding injuring plant roots from over watering, poor nutrition, over-fertilization, high soluble salts or poorly draining potting mixes. Twice the number of fans is recommended for this crop than are needed for other bedding plants. Minimize leaf wetness by avoiding overhead sprinkler irrigation or watering only when plants will dry quickly. weeds while allowing larger plants like shrubs and bulbs to grow well. The leaves should uncurl when the temperature drops again. Spores are easily spread by air currents or in water. Disease Cycle. These profits occur when selling price exceeds total costs (fixed plus variable) or $1.08 per plant in this situation portrayed in the enterprise budget. For information or the status on programs, contact your local Extension office by email or phone. Use them with caution in gardens that are accessible to 1219, The University of Georgia 2020 | All rights reserved. Always use fresh potting media when planting. Disease Cycle. Konjoian. Keep the mulch two to three inches away from the plants' stems to prevent the development of rot. * Keep iron concentrations at or below 1.0 ppm if using a chelated iron source. Both pH and alkalinity are important in making decisions concerning proper water treatment. Vinca minor grows best in shady, well-drained Why can't you grow quality vinca? Greenhouse owners can increase airflow by simply installing additional HAF fans. Make sure your vinca has plenty of sunlightfull sun is bestand that its planted in well-drained soil. Nutrient deficiencies of Vinca. Infected plants may die within 1 to 2 weeks following symptom development. Some of the newest lines being evaluated at the University of Georgia include the 'First Kiss' series and the 'Garden Leader Splash' series. Using a nitrate-based soluble fertilizer such as 15-2-20 will give excellent stretch control unless conditions such as temperature are extreme or problems exist due to crowding or low light. 82-83. Typically two to three applications may be necessary to protect the crop. Researchers have documented that vinca do not like elevated levels of ammoniacal nitrogen (>25 ppm) or phosphorus (>20 ppm) in the soil. centers in late spring. Our industry must do a better job informing landscapers, garden center managers and consumers on the cultural requirements of Vinca. Since we are recommending growing on the dry side of moist, there is very little room for error. Vinca is a specialty crop with very distinct requirements. centers in the spring and summer, but they are used in the garden completely
After a few new leaves have expanded, the rate can be increased to 125 ppm.
This is especially true of 2-week-old seedlings. Black root rot, caused by the fungus Thielaviopsis basicola (also known as Chalara elegans), is a widespread and destructive root disease of several annual bedding plants includ-ing vinca, pansy and petunia. NAU, J. An example is the Magic Carpet series. Estimated variable costs of producing vinca in Georgia, Zone 7, 2002. Madagascar periwinkle, Rose periwinkle, or just Vinca. While technically a Temperatures at night below 55 degrees F will cause leaf rolling, chlorosis, leaf drop and sometimes a purpling or bronzing effect on leaf tips. Never use green or poorly composted bark as a soil medium for vinca. This kind of mix can be purchased through most soil distributors, or you can make your own by adding up to 25 percent perlite by volume to your usual soil mix. Ball Pub. Each group defines a growing characteristic that may make its use for a particular basket or pot a good experience or a poor one. Keep the soil salt concentration, electrical conductivity (EC), below 0.75 and don't hesitate to leach if you feel salts are building up or if an excessive amount of fertilizer was accidentally applied. Lower leaves of infected plants often yellow. How-To, Plant Care, geranium, pelargonium, seasonal care. Soil left on benches or containers between crops can harbor Rhizoctonia. Order mixed annual combinations ready to plant in your containers. Flowers and leaves are smaller than normal. Botrytis produces abundant spores on infected plant tissues. Accept poorly rooted plugs and you accept all future risk, which will be greatly enhanced by poor root systems. reliably all summer. Most foliage diseases of vinca are caused by fungi and are often favored by extended periods of leaf wetness. Normal foliar analysis ranges for vinca grown in soil-less medium*, * Source: Plant Analysis Handbook II. Elizabeth Balarini is a freelance writer and professional blogger who began writing professionally in 2006. Keep the EC below 1.0. Cultivars in commercial production up to the early 1990s had many problems, including very weak stems, poor tolerance of wet weather and susceptibility to many diseases. You will find many uses for vinca in the garden center market, and you may be tempted to use every container at hand, but beware -- the drainage required to grow and maintain vinca in a container is critical. Chilled plugs may recover nicely if allowed to warm up slowly over a day or two without stress. Use according to label directions. Vinca is a genus of flowering plants in the family Apocynaceae. Weather and scheduling problems may result in the need for height control techniques. This bulletin will address those requirements and cover a typical production schedule and crop budget. Ground cover vincas can be exuberant growers, so Because vinca has so many uses, many different schedules can produce a quality crop depending on the container you choose to use. Sufficient air movement that allows leaves to dry is crucial. Do not contaminate soil or containers by placing them on dirty benches or floors. This holds true of most bedding plants. Vinca (Catharanthus roseus), commonly referred to as Periwinkle, is an evergreen perennial that blooms in the spring and summer. To meet these soil temperature requirements, again, growers should dedicate a whole greenhouse to it; adapt a section of the greenhouse for warmer temperatures and use bottom heating devices. Using perlite or other amendments to increase porosity is essential. When trying to control stretch on plugs, do not use the "spray and chill" technique to hold plugs or plants. Low soil fertility also increases disease severity. Make sure that large particles of bark or small gravel are placed at a depth of 2 inches prior to adding the soil and plants. Avoid this problem by monitoring soil pH often. With proper care, you can expect beautiful bright blooms through the end of the fall season! These are general estimates, as each greenhouse and production program can affect the speed of development. Greenhouse Manager Magazine (GMPro) Sept. 1992 pp. In all cases, keeping night air and soil temperatures above 75 degrees F will yield a rapid crop turnover. Be especially careful when using chelated iron sources that have iron-DPTA or iron-EDTA. Hardy in U.S. Department of Agriculture plant hardiness zones 9b through 11, vincas thrive in full sun and require temperatures no colder than 60 degrees Fahrenheit. Symptoms of virus infection are variable. Never re-use potting media for any reason. Use new containers for each planting and keep all equipment and the planting area clean of old potting media and debris. We have faculty and staff in every county across the state that are available to assist you. Inspect vinca crops each week and discard any pots or flats with infected plants. Mix 1 teaspoon of fertilizer with 1 gallon of water, or according to the instructions on the package. Also, minimize wetting plant foliage when irrigating as much as possible. bedding out, space them 8 to 10 inches apart. a pink center. Clean benches and floors of plant debris from previous crops and disinfect propagation and production areas including transplanting equipment and re-used pots or flats. The flower is native to Europe, northwest Africa and southwest Asia. necessary only if plants start to droop. Bulletin full sun south of USDA Zone 7. You might fertilize your vinca once or twice over the summer to help them continue blooming. Colorado State University Denver County Extension Master Gardener: 2002: The Year of the Vinca, How to clean a showerhead, according to an expert. For severe problems or when holding a crop is essential, foliar sprays of Sumagic are effective in holding crops under high heat. New colors, more vigorous cultivars and improved cultural information will increase consumers' success rate. Once damaged, the roots rarely regain vigor and potential disease penetration is increased. Management. High soluble salt concentrations in the potting medium also favors Pythium infection by stressing the root system. give them plenty of room to spread, and trim back if necessary to contain them. Using less refined, chunky peat in your mix is preferred over using ultra fine particles. Sanitation within the greenhouse is critical for controlling Phytophthora diseases. Excessively wet soil can cause fungal diseases such as blight or leaf spot. We suggest adjusting the pH down to at least pH 5.6. The soil fertility is poor and, therefore, vinca is adapted to a low fertility environment. Newly planted Vinca should be watered well until established. Try to keep cool-day treatments between 63 and 65 degrees F and never below 55 degrees F. If auto-mated, be sure no pockets of very cold air are generated during the cooling process. Currently, there is no control for TSWV in ornamentals. With vinca, the larger plug sizes also have an advantage in that the increased amount of root system greatly improves survival and regrowth after transplant. Both fungi cause small (the size of pinhead, up to 1/8 inch in diameter) brown to black spots on the leaves, stems and petioles of infected plants. Grower Talks Magazine, p. 63-69. When establishing new plugs in a new soil, irrigate with a solution of 50 ppm 20-20-20. We will personally assist with your needs during our normal business hours (Monday through Friday, 8am to 5pm). Make the cut 1/8 to 1/4 inch above the second set of leaves using a pair of pruning snips. The leaf spots caused by the fungi Ulocladium sp. Disease cycle. Do not plant in Keep the EC below 1.00 mmhos/cm for seedlings at all times. Severe or prolonged deficiency causes leaves that are thin, strap-like but still green. shades of blue. Applying azoxystrobin, fosetyl-Al with or without a mancozeb tank mix as a heavy spray/drench ("sprench") at least monthly can reduce disease development and spread. To accomplish this, you must undertake simple but important changes in your growing program. Newly maturing leaves may become strap-like and cup downward. Address water quality issues for successful vinca production before production begins. Adjust your schedule according to your local market. Table 5. Vinca are very sensitive to iron toxicity as well. The series 'Tropicana' and 'Pacifica' perform well in seemingly excessive heat and humidity, and are fast becoming a favorite in the south. Periwinkles are easily found in garden Thomas, P.A., and J.G. Damping-off usually occurs when seeds are planted into contaminated potting mixes and containers or when the potting mix becomes contaminated by poor sanitation practices. GM Pro Magazine. Wash off small insect populations with a steady stream of water in the morning. New growth and buds are tight and bunched. Hourly scouting is essential. If the area is stuffy or overly humid, theres a higher chance of mildew forming on the plant. Step 1 - Water only when the soil is dry. Water sources with a pH level above 7 and high alkalinity are likely to cause a significant pH drift in the growing medium. Shipping or holding vinca plugs at temperatures of 50 degrees F may cause serious chilling injury. Four hours of light at 1500 fc provided via "High Intensity Discharge" (HID) lamps is optimal. This will allow the excess water to drain out or evaporate throughout the day. Dwarf Type Vinca have smaller flowers, form denser plants and have a more upright character than the carpet type. network of committed specialists, agents and volunteers to help Georgians learn, grow and do more. Spread a 1- to 2-inch layer of mulch around the plants with a trowel or garden fork. small children. Plant Analysis Handbook II. Watering in the morning is best to give the soil a full day of sun to drythis helps to prevent fungal growth. Given an expanded role as a basket or color-bowl crop, the potential for sales of this crop is good. Purchasing larger plugs, such as 144s, provides more root development in relation to the pot it is planted in and reduces the time it takes for roots to grow throughout the new media. Water every other week, or if the top 2 inches of soil feel dry to the touch. In addition, avoid fertilizers high in ammonium as a nitrogen. Disease Cycle. However, cease ammoniacal fertilization once the seedling root system begins to grow and hold the new soil. Vinca can be infected by the usual root rot pathogens including Pythium, Phytophthora, Rhizoctonia and Thielaviopsis. Border Type Vinca have larger 2-inch flowers, are more vigorous and form upright mounds 14 to 20 inches tall. J. Thrips, spider mites and mealy bugs are the three kinds of insects known to infest this crop. Shade cloth is commonly used to reduce light levels and heat load in the greenhouse. During particularly dry summers or drought conditions, you may see Vinca leaves curl up. GSCO just got a fresh shipment of vinca in last week! Container medium and slow-release nitrogen fertilizer influence growth and qual-ity of Salvia farinacea. Remove all plant and soil debris from greenhouse benches and floors. Management. Keep light diffuse and overall levels moderate -- or more specifically, between 2000-2500 fc for plugs. Disease Cycle. Ball, Jr. sunny flower beds and containers. Table 3C. If receiving plugs, transplant plants within 24 hours for best results. You have successfully removed your county preference. for folk medicine, especially for treating diabetes, and are the source of 1996. No special care Given the recent drought years, sales of vinca for the landscape, for specialty baskets and for large city containers is strong and will likely re-main strong. We try to grow vinca warm and sunny, but the amount of heat a greenhouse cooling system can handle will affect how much light vinca should receive late in the production season. Phytophthora typically infects the main roots near the crown and often causes a crown rot. It is deer-resistant and easy to Most growers involved in the production of large numbers of decorative pots or hanging baskets set aside one Quonset section just for vinca. This page contains affiliate links to products on Amazon. All are damaging and can kill infected plants, but Thielaviopsis, the cause of "black root rot," is the most serious root disease primarily because it is very difficult to control. Then following pupation, the winged adults transmit the virus when feeding on a plant. Put a small 512 plug in a 4-inch pot where the soil is likely to stay wet due to the small root system, and you will increase the chances for disease and root damage due to over-watering. Think air movement. Overwatering this plant can be harmful and it is difficult for the plant to recover. and Alternaria alternata, are very similar. (ed.) Warmer, wet conditions favor infection. If vinca is watered too late in the day, the excess water remains on the plant all night.
Leaves are dark green and glossy, but root development may be reduced by nearly 70 percent. Vinca shows rapid micro-nutrient deficiencies when grown in soilless mixes with a pH above 6.3. Even at 75 ppm, fertilizer salts concentrate and can cause root damage.
Management. Those who implement the growing program changes will see how trouble-free and profitable this crop can be. Vinca requires higher light level and air movement and they have different watering and fertilization requirements than the average bedding plant, such as marigolds, begonias and impatiens. * Use of vinca at this density allows a 2-week reduction in bench use; this density requires nitrate-based fertility and careful temperature control to avoid stretching. Your staff may be successful in managing the soil water status in reservoir baskets, but your customers will likely not have developed that skill. Manual transplanting by crews unaware of the fragile nature of vinca's roots is the most common cause. Germinate and grow vinca seedlings in the highest porosity peat-lite plug-mix you can get. They make mounded plants 1 to 2 feet high and wide, and bloom Get plant information, garden quotes, & exclusive offers directly to your inbox. Do the best you can to increase the hours of light when growing an early spring crop. Night temperatures must be kept above 65 degrees F, or the crop growth rate will slow down. The fungus will survive and may cause root rot in the remaining plants once the concentration of the fungicide declines. Larger plug sizes perform better, grow quicker and are essential for early spring crops started in February. They are not particular about droughts, although vinca grown in sun may require occasional watering. It takes time, but it may mean the difference between a very disappointing season or a big success in future years. Pull up any weeds growing around the vinca. Improving air flow through the vinca crop greatly reduces the potential for most foliar disease problems. Thomas, P.A. Switch to every other day watering during the second week. These older hybrid lines of vinca were bred for flower color, not vigor, and tended to be weak-rooted and much more demanding in their environmental requirements, especially when young. The secret to growing and maintaining high quality plants is maintaining an optimal root environment. Southern growers will receive more benefit from DIF if the crop is shaded a week prior to treatments and light levels are held under 3000 fc. However, if you wish to grow vinca from seed, the following is how professionals handle the process. Very humid greenhouse conditions, over-watering, overhead landscape irrigation and prolonged rainfall can affect vinca adversely. Effect is temperature dependent. Vinca roseus (also known botanically as If the soil has high salts or a heavy fertility is present, low water use can cause salt damage of new transplants' roots. soil, and in fact do well in poor soil with low fertilization. Its ability to persist in greenhouses for long periods of time make managing the disease very difficult. Mills, H.A., and J.B. Jones. Learning to recognize these symptoms will help manage production problems before they become serious and delay the crop. Always use fresh soilless potting mixes and sterile flats, trays or pots to start seeds. This plant can suffer from sitting in wet soil for too long. Mix 1 teaspoon of fertilizer with 1 gallon of water, or according to the instructions on the package. Growth of vinca as affected by form of nitrogen, presence of bark, and type of micro-nutrients. Stop by today to grab yours. Remember, too, that fungicides only control fungi and, to a very limited extent, some bacterial pathogens. Reston Publishing Co., Reston, VA. pp. For example: The 'Victory' series has intense, clear colors and a compact growing habit. The 'Heat-Wave' series and the cultivar 'Santa Fe' are promising and also appear to be more tolerant of warm, dry weather than other cultivars and may be a better selection for southern growers. Because facilities (capacity, age, cost, use) may vary from grower to grower, considering only the variable or direct costs of production and marketing over a 10 percent range above to below the budgeted total variable costs of $2,258, and a 10 percent variability in output above to below the anticipated number of salable plants (2,462) in the chart above, shows the cost-output sensitivity of producing and marketing vinca. For this same reason, if your vinca is planted in a partially shaded area, make sure it has good airflow. Discard or destroy all plant debris at the end of the production cycle or at the end of the season after the first hard frost to reduce pathogen survival. Some authorities firmly place the 'Cooler' series in the border class, as with warm-weather culture they match the other series in plant and flower size. Paul Thomas1Jean Woodward2 Forrest Stegelin3 Bodie Pennisi4. Watering vinca is an art and a science. Practice good sanitation within the greenhouse. They take planning and the same cultural care once placed in the landscape, however. 1990. *The requirement for sulfur is not clear in this species. Get weekly updates sent to your inbox with the latest UGA Extension news. Although it may be possible to identify some diseases based upon symptom description, many diseases need to be submitted to a county agent for assessment by a state extension plant disease diagnostic clinic, the University of Georgia Distance Diagnostic program or a private laboratory for diagnosis. Vinca growers in many parts of the United States have very hard water with pH levels between 8.0 and 9.0. Estimates are that more than 60,000 spores can be produced on an infected plant piece the size of half a dime. The disease is often introduced into greenhouses from infected plugs. Give the plants water only during the morning to allow time for drops of moisture to dry before nightfall. Suggested fertility programs for Vinca grown in soil-less medium. Fungicides can reduce disease spread, but they will not "cure" already infected plants. Trying to plant too soon in the season may cause production delays and poor quality crops. 1992. The development of a strong root system after transplant is essential for success. Height control is most easily achieved by using plant growth regulators (refer to Table 4 for rates). Botrytis blight or gray mold, caused by the fungus Botrytis cinerea, is found everywhere plants are grown. 1993. Always use lower rates first. Because vinca is grown under warm, often humid conditions, airflow is critical. Bedding plants that grow well under conditions optimal for vinca include salvia, zinnia, melampodium, cosmos and cleome. Heating mats are often used to maintain soil for the next 6-7 days until radical emerges in most of the seeds. They do not control diseases caused by viruses. Apply water from a garden hose directly to the soil surrounding the plants. Root growth also is stunted. temperatures drop down to about 50 degrees. Knowles, T.C., B.W. These plants are well-suited for use in large color bowls, large barrels, city planters and large, main-street baskets 15-36 inches in size. Vinca are uniquely adapted to withstanding wilting and temporary drought and will respond well to watering the next morning. Gibson. The round, flat blooms appear on top of 12- to 15-inch stems. creeping myrtle, is the ground cover plant often used where grass won't grow. Soil pH may (usually does) rise for four to six weeks after transplanting. 'Morning Mist' is a border type vinca with remarkable tolerance to heat, and 'Parasol' is an All American Selection winner that has excellent branching and heat tolerance. * See your local state recommendations and be sure to consult the manufacturer's label before using any plant growth regulator. Likewise, holding plugs in coolers while catching up with transplanting is not recommended. Care sheets that accompany each basket would be helpful. Eventually the plants turn yellow with the dark margins very evident. Plan the perfect garden with our interactive tool , Alabama Co-op Extension: Diseases of Annual Vinca in the Greenhouse and Landscape, Colorado State University Denver County Extension Master Gardener: 2002: The Year of the Vinca. If water is not present on the leaf for the required time, then the fungus cannot infect and cause disease. Summer heatparticularly in the Southcan be tough on so many plants. We translate science of everyday living for farmers, families and communities to foster a healthy One of the true strengths of using vinca in a production plan is that the plants are affected by very few insect groups. Between 14 and 21 days, while the true leaves are expanding, it is important to reduce soil temperature slightly again, to 68 degrees F to 72 degrees F for 7 to 10 days, or until most seed has germinated. It is best to discard all the plants and soil in a flat and sterilize the flat before re-use when damping-off occurs. Balarini majored in English at the University of Texas at San Antonio. al. The cluster of fungal spores gives the affected plant part a gray, fuzzy appearance that can be easily seen with the naked eye or with the help of a magnifying glass or hand lens. The most diagnostic symptom on vinca is leaf yellowing (chlorosis) of infected plants. Hot weather speeds up the process. Any activity within a greenhouse can trigger spore release, including irrigation and pesticide applications. University of Georgia Cooperative Extension programming improves people's lives and gets results. Vincas really only require water once their soil has completely dried.
Unless it provides many, many small holes for water release, the "perched water" effect will be extreme and vinca will not survive. Not to fear, though! 11-17. Both plants are commonly found in garden Abundant blooms and ease of care make vinca (Catharanthus roseus) an excellent selection if you have little time to tend your garden.