Are the seedlings dying and the stems are girdled or rotted at soil line?
Are the flowers covered with gray mold, leaves may be blotched or discolored?
Are the leaves yellowing, wilting and, dying?
Are the leaves discolored, fine webbing may be present?
Are the leaves curled and distorted?
Do the leaves and stems have white, cottony clusters on them?
Do the leaves have large, ragged holes in them?
Are the leaves mottled with dark green?
If your seedlings are falling over and the stems are girdled or rotted at the soil line, the most likely cause is a damping-off disease. Remove and destroy all infected plants. To prevent damping-off let the soil surface dry between waterings, thin seedlings to avoid overcrowding and do not add nitrogen fertilizers until plants have developed leaves.
Gray mold on flowers is probably caused by fungal disease - Botrytis blight. You can prevent Botrytis blight disease by planting in areas with good air circulation. Water plants sparsely. Severely infected plants should be removed. Spray weekly with a copper fungicide until the disease is under control.
Yellow leaves that wilt and die usually indicate fungal or bacterial Root rot disease. Poorly drained, overly wet soil promotes rot so choose well-drained sites and add organic matter to improve drainage. Remove and destroy infected plants. Solarize the soil before replanting.
Spider mites are known to cause problems for Ice plant. Hose off plants when symptoms first appear. A strong stream knocks mites off plants and may give control. Introduce predatory mites. For severe infestations, spray plants with insecticidal soap or pyrethrin.
Distorted and curled leaves are caused by aphids. These tiny insects cluster under leaves and on growing tips where they feed on plant sap. Leaves, stems, and buds get distorted and later leaves and flowers drop from the plant. You can control them by washing them off the plant with water spray. Insecticidal soap should be used with severe infestations.
White, cottony clusters on leaves and stems are caused by mealybugs. These tiny insects are covered with a fluffy white coating. They feed by sucking plants sap. They produce sticky substance honeydew which makes leaves sticky. You can control them by washing them off the plant with water spray. Insecticidal soap should be used with severe infestations.
Large, ragged holes in the leaves are caused by slugs and snails. Slugs and snails feed on the plant leaves usually at night. To control slugs and snails use diatomaceous earth around your plants. You can also handpick them during the night or use shallow dishes filled with beer as a trap.
Mottled or streaked leaves are caused by Mosaic virus. There is no cure for infected plants. Remove and destroy all flowers that have the symptoms of the mosaic virus. Mosaic virus is spread by aphids, so the best way of preventing the disease is to control these insects.
If the edges of the leaves have been notched the culprits are vine weevils. To control them, spread a drop cloth around your plant and shake it so the adults drop. You can get rid of them after that. Spray leaves several times with pyrethrin for major infestations.
https://www.burpee.com/gardenadvicecenter/encyclopedia/annual-flowers/learn-about-ice-plants/encyclopedia__IcePlants-article.html#howToCommonPests
Ellis, B. W., Bradley, F. M., & Atthowe, H. (1996). The Organic gardener's handbook of natural insect and disease control: a complete problem-solving guide to keeping your garden & yard healthy without chemicals. Emmaus, Pa.: Rodale Press.
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Sreten null
Hi! I’m Sreten Filipović. I graduated from the Faculty of Agriculture at the University of Belgrade, with a master's degree in Environmental Protection in Agricultural Systems. I’ve worked as a researcher at Finland's Natural Resources Institute (LUKE) on a project aimed at adapting south-western Finland to drought episodes. I founded a consulting agency in the field of environment and agriculture to help farmers who want to implement the principles of sustainability on their farms. I’m also a founding member of the nonprofit organization Ecogenesis from Belgrade whose main goal is non-formal education on the environment and ecology. In my spare time, I like to write blog posts about sustainability, the environment, animal farming, horticulture, and plant protection. I’ve also published several science-fiction short stories.
You can find me on LinkedIn at https://www.linkedin.com/in/sreten-filipovi%C4%87-515aa5158/