Are there any small translucent spots on leaves, spots later turn black?
Does the mass of brownish mycelia covers the foliage of your Fittonia?
Does your plant suddenly wilts and dies?
Are the leaves distorted and yellow?
Do the leaves and stems have white, cottony clusters on them?
Do the leaves have large, ragged holes in them?
Are the leaves covered in coarse stippling and may appear silvery?
Are the leaves stippled, reddish or yellowish with fine webbing?
Bacterial leaf spot causes circular translucent spots scattered over the leaf surface between the veins. These spots turn brownish-black and may spread to form large patches of dead tissue. To prevent the spread of this disease, avoid working around wet plants. Remove and destroy affected parts. Spray Bordeaux mix on remaining plants.
Rhizoctonia aerial blight is a fungal disease that is known to attack Fittonia. Rhizoctonia mycelia are usually reddish-brown and have the consistency of a spiderweb. Good chemical control of Rhizoctonia aerial blight for most foliage plants may be achieved with weekly sprays.
Southern blight is a fungal disease that can infect Fittonia. All infected plants and the pots they are in should be removed from the growing area and destroyed as soon as they are found. There are no chemicals that are safe, effective, and labeled for this disease on fittonias.
Distorted, yellow 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 the 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.
These symptoms may indicate thrips. Thrips are tiny, yellow to black flying insects. Severely infected plant parts should be removed and destroyed. Control thrips by introducing lady beetles or lacewings, their natural predators. Insecticidal soap helps in severe infestations.
Reddish to yellowish flecks on leaves and webbed foliage indicate spider mites. These tiny, spider-like pests feed by sucking sap from the underside of the plant leaves causing yellow flecking on the upper leaf surfaces. You can control spider mites by spraying plants thoroughly with water 2-3 times a day for several days. For severe infestations, spray plants with insecticidal soap, or pyrethrin as a last resort.
If there is chewing damage on the roots the culprits are fungus gnats larvae. Adults are little flying pests in the house. Allow your plant’s soil to dry out between waterings. The larvae prefer constantly moist or wet soil, and will not thrive when the soil starts to dry out. Neem oil sprayed on the soil’s surface and the plant can help keep adults away.
https://mrec.ifas.ufl.edu/foliage/folnotes/fittonia.htm
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/