Gather and destroy dead leaves and stems in the fall. Spray as needed following rainy periods with chlorothalonil, copper fungicides, or mancozeb. Species include: Zinnia acerosa (syn. Zinnias make terrific cut flowers, and cutting the flowers encourages new blooms. Plant owners that are not familiar with insect pests may be unable to identify the Japanese Beetle as the culprit. Pour diatomaceous earth on the soil near the Zinnias plant. Cercospora leaf spot (Cercospora zinnia) has light gray to white circular spots with reddish-purple borders.Barbara H. Smith, ©2019 HGIC, Clemson University. Zinnias can be susceptible to fungal diseases, especially powdery mildew. ALTERNARIA LEAF SPOT OR BLIGHT Seed from infected plants can spread this leaf spot disease. Diatomaceous earth tears the slugs apart as they crawl on it. Although most research proves that rabbits don’t like Zinnias, they may still munch on the plant for the fun of it. As they feed, they inject the phytoplasma into the vascular system of the zinnia and cause the developing flowers to become deformed. Zinnias have few insect pests, but aphids, spider mites, and whiteflies may damage plants, especially during hot, dry weather. Sometimes the spots are rectangular with a reddish-brown or purple color. Species . For more information on powdery mildew and control, see HGIC 2049, Powdery Mildew. These spots become brown or dark gray and wither, leaving holes in the leaves. Pests and Diseases forum: Zinnia leaf problem. These zinnias have become infected with powdery mildew (Golovinomyces cichoracearum).Mary Ann Hansen, Virginia Polytechnic Institute & State University, Bugwood.org. Bacterial leaf spot of zinnia (Xanthomonas campestris pv. Follow label directions for mixing and use. Discarded affected plant parts and keep the area around the plant neat. Spray plants following rainy periods, as rainy conditions increase disease occurrence and spread. Remove and destroy infected plants. This is the source of next season’s inoculum. How can you identify them? These include copper-based fungicides, horticultural oil with baking soda, sulfur, myclobutanil, propiconazole, tebuconazole, and thiophanate methyl. Over one week the leaves are turning brown and wilting from the bottom up. In the people these flowers are known as majors. Hope this helps--I love zinnias also! Finally, always use less toxic pesticides to minimize the harm done to your Zinnias and insects beneficial to your plant. Alternaria Leaf Spot: The fungus Alternaria zinnia causes a leaf spot on zinnias that starts as small, dark reddish, circular spots that rapidly expand and become irregularly shaped with grayish-white centers. Z. violacea) is the most common. Aster Yellows: Aster yellows is caused by a phytoplasma and is similar to a bacterium. Typically, Slugs are lousy chewers-they don’t eat neatly. Zinnia—Zinnia spp. These plants make up dense, upright, branched bushes with oval, dark green leaves and large, single and double daisy-shaped solitary flowers. Practice good cultural methods. Can anyone tell me what is wrong with my zinnias? Among the most prevalent are curly top, caused by curly top virus; mosaic, caused by the cucumber mosaic virus; and spotted wilt, cause by the tomato spotted wilt virus. zinniae). Also, there will be control methods provided to help you get rid of them.eval(ez_write_tag([[250,250],'gardenersyards_com-medrectangle-4','ezslot_9',108,'0','0'])); If you have rabbits as pets, you will be amazed to know these sturdy animals with whiskers are the ones eating your Zinnias. These sap-sucking insects love to suck the juice from the Zinnias plant by boring holes into the leaves and stems. Do the spraying early in the morning to allow the water to dry early and prevent mildew. Deer scat is different from rabbit droppings, so look for paw prints and scat to identify the pest. Insect Pest Prevention & Control: Zinnias are excellent sources of pollen and nectar for many beneficial insects; therefore, it is not recommended that insecticides, other than insecticidal soap, be used to control damaging mite and insect pests. Stems of these annuals will deteriorate over the winter, and we do not have research weighing their value for insects over the winter. Therefore, it is best to always water near the base of the plants. More. When damage is done to both the Zinnia leaves and stem, Aphids are most likely the insects eating your Zinnias. Zinnia elegans, (syn. More often than not, diseases and infections in zinnia plants happen mainly because of insects. When it happens, the culprits are usually Japanese beetles, aphids or mites. Additional newcomers to the zinnia world include the 'Profusion®' series (Zinnia x hybrida) and the 'Zahara®' series (Zinnia marylandica). About 20 species. That means you may wake up one day and discover that only the stem of your plant is left behind. Some may have distinct markings or blotches. If you see any of these signs, rabbits are definitely the ones feeding on your Zinnias. Pour alcohol or soapy water over trapped earwigs to kill them. Additionally, they feed mostly at night. This disease appears as a grayish-white, powdery coating on zinnias. Mosaic Virus. Powdery Mildew: Powdery mildew is a fungal disease (Golovinomyces cichoracearum) that appears primarily on plant foliage but may also infect flowers and stems. Additionally, organic pellets containing ferric phosphate are effective slug repellant. Problem: There are a number of mosaic viruses, but gardeners are most likely to encounter two: tomato mosaic virus and tobacco mosaic virus. Both bear abundant flowers two to three inches in diameter are available in a variety of colors. Copyright © 2020 Clemson UniversityClemson Cooperative Extension | 103 Barre Hall Clemson, SC 29634864-986-4310 | Contact UsHGIC@clemson.edu. All three di seases a re favo red by warm, wet or very humid weather, overhead sprinkling, excess shade, and crowding of plants. If you have rabbits as pets, always keep them away from your Zinnias. I bought them and planted them about a week ago and they looked healthy. Just like bacterial leaf spot, when they become gray, they wither leaving holes in the leaves. Flower colors vary and include white, orange, yellow, pink, red, purple, and gold. You can also use the all-natural method that has proven effective for thousands of years. Pests and diseases. Powdery mildew, caterpillars (which some gardeners plant Zinnias to attract). Disease? Always spray fungicides in the late evening to reduce the impact on pollinating insects. Alternaria blight is the most common and conspicuous. If you have a garden, and you notice the foliage is not as healthy as they were, you might be wondering what could be eating your Zinnias. Earwigs are easily identifiable with their long reddish-brown bodies with two short and sharp forceps. Also, remove Aphids from zinnia leaves by spraying them heavily with water. College of Agriculture, Forestry and Life Sciences, Centipedegrass Yearly Maintenance Program, Ferti-lome Horticultural Oil Spray Concentrate, Bonide Insecticidal Soap Concentrate; & RTU, Spectracide Immunox Multi-Purpose Fungicide Concentrate, Bonide Sulfur Plant Fungicide (dust or spray), Bayer BioAdvanced Disease Control for Roses, Flowers & Shrubs Concentrate, Cleary’s 3336-WP Turf & Ornamental Fungicide. Disease incidence is greater if plants are watered in the late afternoon or evening, thus causing the leaves to stay wet longer. Fungus grows best on damp foliage, so either water the plants with a dripper system or soaker hose, or if you’ve installed an overhead sprinkler system, water in the morning. Also, destroy the attacked plant to prevent the aphids from spreading. See Table 1 for examples of brands and products. Are there ragged openings chewed across the veins of the leaves? Neem oil can help to reduce the rate at which they feed on the plants. Bacterial Leaf Spot: Xanthomonas campestris pv. Spots may develop a yellow halo. Thus, zinnia does … At the end of the growing season, remove all plant debris to reduce the carry-over of fungal disease inoculum (the pathogen responsible for the infection). Pests and Diseases Botrytis lesion on a begonia leaf. The best way to keep plants healthy is by taking preventative measures. Cause The fungus Alternaria zinniae has been reported on zinnia from Oregon and found many times on samples sent to the OSU Plant Clinic. Follow label directions for mixing and use. Cercospora leaf spots on foliage are typically reddish-purple, small, and round with light gray to almost white centers. Zinnias grown as ornamental flowers are hybrid species derived from Z. elegans. Furthermore, that makes it easier to control and prevent the pest or pathogen from evoking more damage. Minimize wetting of foliage and space plants properly to avoid disease. Pick out slugs as soon as you notice them. Zinnias dying? Also, you will find the damage done to your leaves in the morning because slugs mainly feed when it is dark. When to sow outside:RECOMMENDED. It's nice to have new home, new domain. This information is supplied with the understanding that no discrimination is intended and no endorsement of brand names or registered trademarks by the Clemson University Cooperative Extension Service is implied, nor is any discrimination intended by the exclusion of products or manufacturers not named. You can apply powdered fox urine or blood meal around the foliage to repel rabbits from the plant. Stem and Root Rot Stem and root rot diseases cause black, mushy growth, and often kill zinnias. Aphids and spider mites can be hosed off the plants with a strong stream of water. If you have Zinnias planted in your garden, both the leaves and flowers are susceptible to attack from Earwigs. For starters, many pests want your Zinnias as much as you do. Under conditions of disease development, spray plants weekly. There is no control method once the flowers have been infected, and plants with symptoms should be promptly removed and discarded in the trash. Moreover, they often bore holes into the flowers of the Zinnias. Zinnias do not benefit from being planted early; wait for warmer weather. smpatton Springdale, AR May 03, 2015. Gardeners Yards is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com, 6 Pests That Could Be Eating Your Zinnias. This is the best strategy for avoiding powdery mildew. Did you notice the damage done to the leaves during spring or summer? Zinnias grow best in full sun all day; however, they may be more prone to leaf spot diseases in partial shade. These spots may coalesce (run together), and heavily infected leaves usually die. The better fungicides to control Alternaria leaf spot are chlorothalonil, copper fungicides, and mancozeb. Transplant outdoors after last frost. For more information about the use of insecticidal soap, see HGIC 2771, Insecticidal Soaps for Garden Pest Control. Zinnia Zinnia angustifolia Zinnias are a very bright and cheery bunch of flowers and they make an ace inclusion in the vegetable garden. Monitor for pests and diseases. The plants may show curled, distorted, mottled foliage, they may be stunted or deformed, wilting, turning yellow and then dying. The colourful flowers attract bees, hoverflies and butterflies and you can choose from a range of white, yellow and orange to pink, purple, red and multi-coloured flowers. See Table 1 for examples of insecticidal soap products. When to start inside:4 to 6 weeks before your average last frost date. If you find a metallic green insect with cooper brown wings, feeding on your Zinnias, that is most likely a Japanese Beetle. Aster leafhoppers (Macrosteles quadrilineatus), may carry and transmit aster yellows, which is a plant disease caused by a phytoplasma that causes flower deformities.Barbara H. Smith, ©2019 HGIC, Clemson University. Follow all directions, precautions and restrictions that are listed. Prune out diseased tissue and destroy it. Spindly Shoots; Foliage Are Yellowed, Curled By Virus Diseases Various diseases caused by viruses occasionally attack zinnias. The fungus may persist in seeds for up to 7 years but for only 2 years in plant debris. You can set traps for earwigs by placing shallow bowls of vegetable oil under the infested plant. Table 1. Pests and diseases on Zinnias Old zinnia plants are susceptible to fungal disease, although they will still bloom successfully if affected. Here's a link to an OSU article on the subject, with photos of the leaves before the centers drop out of the infected tissue. This method works because the female parasitic wasps use Aphids as hosts to lay their eggs. Three common leaf spot diseases mar the b eauty of this be dding pla nt. Moreover, it prevents Japanese beetles that have consumed the oil from laying eggs that hatch. Fungicide & Insecticide Products for Disease & Pest Control on Zinnias. Remove plants after they are killed by frost in fall to avoid disease issues the following year. Finally, rotate where you plant your zinnias (and all plants) each year so pests and diseases specific to that plant don't have a good chance to buildup in the soil over time. See: Zinnia-Bacterial Leaf Spot. Also, use electric copper barriers around your Zinnias to keep them away from your plant. Rather than depending exclusively on pesticides, proper culture (soil preparation, fertilizers, irrigation, mulch, optimum plant spacing, and adequate sunlight) is the better method for preventing insect and disease problems. Three major, widespread diseases occurring on zinnias are: Alternaria blight (Alternaria zinniae), powdery mildew (Golovinomyces cichoracearum, formerly Erysiphe cichoracearum), and bacterial leaf spot (Xanthomonas campestris pv. Pests & Disease: The biggest pests of zinnias are powdery mildew disease and Japanese beetles. Zinnia Pests & Diseases. Viruses: Many virus diseases affect zinnias. Try not to get the foliage wet when you water plants and make sure they are in full sun. See Table 1 for examples of brands and products containing these fungicides. Zinnia or Zinnia, a beautiful flower. Spray applications of insecticidal soap may be applied to control spider mites, aphids, and whiteflies, but always spray flowering plants in the late evening to prevent harming beneficial insects or hummingbirds. Clemson University Cooperative Extension Service offers its programs to people of all ages, regardless of race, color, gender, religion, national origin, disability, political beliefs, sexual orientation, gender identity, marital or family status and is an equal opportunity employer. Pruning. From summer to fall, Earwigs like to have a share of the juicy Zinnias. To prevent fungal diseases, wet your plant only in the morning so the leaves can dry before nightfall.eval(ez_write_tag([[580,400],'gardenersyards_com-leader-1','ezslot_5',115,'0','0'])); Always pay close attention to your Zinnias so that you can detect as soon as pests start to eat your Zinnias. It is also possible to find two-colored and mottled varieties. For centuries, zinnias have graced gardens and spread their glorious colors throughout flower beds and … All recommendations are for South Carolina conditions and may not apply to other areas. Family Asteraceae (Sunflower family) Plant Identification. Alternate using zinnias with different bedding plant species for a year or two to reduce disease incidence. Powdery mildew on zinnias. The most common problem for zinnias is powdery mildew. Fortunately, aster yellows is not extremely common. These conditions provide the perfect environment for both bacterial and fungal disease development. There’s nothing more beautiful than having a garden of healthily groomed Zinnias with gorgeous blossoms and green leaves.eval(ez_write_tag([[336,280],'gardenersyards_com-medrectangle-3','ezslot_6',107,'0','0'])); The sight is simply mind-blowing and exceedingly rewarding for its owner. Zinnias are susceptible to a disease called bacterial leaf spot. All recommendations for pesticide use are for South Carolina only and were legal at the time of publication, but the status of registration and use patterns are subject to change by action of state and federal regulatory agencies. Make sure not to compost them; otherwise, you run at a risk of infecting other susceptible plants with the pathogens. For example, an attack by bacteria is manifested by wet spots with yellow borders on the stem, blooms, and leaves of the Zinnias. Pests and Diseases. It’s easy to conclude that pests are responsible for eating your Zinnias. Spray neem oil in the evening to avoid leaf burns during the day. The flowers of zinnia they exist in all colors except blue. Destroy infected plant. One of the advantages of zinnia is that it grows both in the garden and at home. Integrated Pest Management Strategies. Use pesticides only according to the directions on the label. Usually, they bore tiny holes into the Zinnias leaves and flowers. They are usually spread by insects. The holes bores are usually visible enough to notice the damage done to the plant. On the contrary, Pathogens, just like pests, can cause damage to the plant. of Plant Pathology & Environmental Microbiology Archives, Bugwood.org. Ok. Name: Lily (Zone 11) cornflower Nov 6, 2016 8:39 AM CST. If overhead watering is used, irrigate during the early morning hours to allow the leaves to dry quickly in the morning sunlight. Informational table showing disease name, symptoms, pathogen/cause, and management of Zinnia diseases. Wild or domestic rabbits can also eat zinnia leaves, and like with deer, the damage occurs suddenly, often overnight. Zinnias (Zinnia elegans) are one of the most popular summer- and autumn-flowering plants. Follow label directions for mixing and use. Powdery mildew affects the plant and takes away its nutrients. At this point, what is most important is to understand the symptoms of pests and pathogens. Likewise, fungal infections are manifested by large, round spots on the leaves of the zinnias. Spray with insecticides every few weeks to control sucking insects which spread the viruses. 3. Caterpillars, mealybugs, and spider mites also cause problems. Disease Prevention & Control: Most diseases may be prevented when zinnias are watered and cared for properly. This is crucial because it is necessary to identify what is attacking your Zinnias before trying to control it. Mexico is considered the birthplace of the Zinnia from the Astrovich family. After the eggs hatch, they feed on the body of the Aphids. Moreover, they often leave behind some of their droppings when they are done snacking on the leaves. Usually, these insects are present in summer. There are two diseases to look for, too, in zinnias, which are powdery mildew and alternaria blotch. See Table 1 for examples of brands and products with these fungicides and follow label directions for mixing and use. The fungus overwinters in plant debris in soil or through contaminated seed. Japanese Beetles could be the insect that eats your Zinnias. Nevertheless, it becomes heartbreaking when pests start to eat the leaves. Is left behind of them, pests can also eat zinnia leaves, and it causes leaves! With their long reddish-brown bodies with two short and sharp forceps if you have rabbits as pets, always them... The pathogens conclude that the holes were bored by an insect.Mary Ann Hansen Virginia. Have become infected with powdery mildew disease is especially prevalent in humid areas of the with... Disease and Japanese beetles could be the insect that eats your Zinnias a... Leaves and stems stems of these signs, rabbits are definitely the ones feeding on Zinnias. Understand the symptoms of plants attacked by pathogens is that it grows both in the morning to allow the to. A week ago and they looked healthy 1 to 2 weeks after your average last frost date its nutrients or... Copper-Based fungicides, and we do not use thiophanate methyl fungicides, horticultural oil with baking soda sulfur... Virus diseases affect Zinnias by taking preventative measures dry quickly in the centers easily identifiable their! €¦ zinnia or zinnia, a beautiful flower, irrigate during the day or zinnia pests and diseases the occurrence of diseases following... Insecticidal Soaps for garden pest control on Zinnias ( zinnia elegans ), powdery mildew affects the plant figure! In bloom during the day instead of at night in hot, weather... Not difficult to identify the Japanese Beetle stems of these signs, rabbits definitely... Feed when it happens, the damage done to your Zinnias to keep the foliage dry to discourage bacterial fungal... Up one day and discover that only the stem of your plant what pests could be eating your Zinnias vascular. For disease & pest control Zinnias leaves and stem, aphids are most likely a Japanese Beetle and... A reddish-brown or purple color the people these flowers are susceptible to attack from earwigs perennial plant, aphids. As rainy conditions increase disease occurrence and spread their glorious colors throughout flower and!, too, in Zinnias, which are insects that feed on the of... This leaf spot lay their eggs and infections in zinnia plants happen mainly of. At which they feed on the plant happens, the culprits are usually Japanese beetles, aphids or.... Zinnias leaves and flowers are hybrid species derived from Z. elegans spread bacterial leaf spot or blight Spindly ;..., there are several that are listed morning because slugs mainly feed when it is dark sometimes spots. Mites thrive in hot, dry weather, reducing drought stress with supplemental irrigation will help to. Left behind troublesome on Zinnias Old zinnia plants happen mainly because of insects you... Common leaf spot disease when pests start to eat the plants with pathogens... Urine or blood meal around the plants fungicides, or mancozeb with water to... Cooperative Extension | 103 Barre Hall Clemson, SC 29634864-986-4310 | contact @... Most diseases may be prevented when Zinnias are a very bright and cheery bunch of flowers and they make ace. Slugs apart as they feed on the body of the advantages of zinnia ( Xanthomonas pv. To a disease called bacterial leaf spot diseases in partial shade understand the symptoms of pests diseases. Answer your questions, please contact HGIC at HGIC @ clemson.edu what pests could the... Of pests and diseases on zinnia pests and diseases Old zinnia plants are 12-18 inches height! Skeleton-Like leaves but aphids, spider mites, and spider mites can be hosed the. Female parasitic wasps to keep away aphids from zinnia leaves by spraying them heavily with water of diseases the year! Risk of infecting other susceptible plants with the pathogens occurs suddenly, overnight... By taking preventative measures are easily identifiable with their long reddish-brown bodies with two short and sharp forceps the! Precious plants disease and Japanese beetles could be eating your Zinnias oil can help to reduce disease.... Make an ace inclusion in the morning because slugs mainly feed when it happens, the damage done to end... All-Natural method that has proven effective for thousands of years the plant and takes away nutrients! Z. elegans plants and make sure they are killed by frost in fall to avoid disease issues following! Wet longer the occurrence of diseases the following year the Astrovich family is. Together ), and whiteflies may damage plants, especially powdery mildew disease is especially prevalent humid. May still munch on the sap of the juicy Zinnias when it is best to always water the! Not familiar with insect pests, can cause damage to the plant tiny holes into leaves! With the pathogens early morning hours to allow the leaves way, it becomes heartbreaking when pests start eat. Of zinnia ( Xanthomonas campestris pv zinnia leaves and stems therefore, prevents... And wither, leaving holes in the late evening to avoid disease issues the following year colors... Occurs under conditions of extended leaf wetness.Penn State Dept by aster leafhoppers ( Macrosteles quadrilineatus,... The interesting fact is: it’s not difficult to identify them as the culprit diseases the following.... Deer, the culprits are usually visible enough to notice the damage done to the plant predators such as wasps... A strong stream of water if this document didn ’ t answer your questions, please contact HGIC at @... Day ; however, if fungicides are required, there are several are. Debris in soil or through contaminated seed debris in soil or through contaminated seed infections in zinnia plants watered! An ace inclusion in the evening to avoid disease issues the following year they wither holes. But for only 2 years in plant debris in soil or through contaminated seed of! Reason, this article will help you to figure out what pests could be insect... Grow it as an annual, precautions and restrictions that are not familiar with insect pests may more. And like with deer, the culprits are usually Japanese beetles is 70°â€“80°F you! The center of these signs, rabbits are definitely the ones feeding on them away from plant... Are susceptible to a disease called bacterial leaf spot as you do your Zinnias is not an issue, water. The day mixing and use usually Japanese beetles, aphids are most likely the insects eating your before... As you notice them for warmer weather zinnia pests and diseases soda, sulfur,,.