Why Does My Amaranth Look Unhealthy?

Are there any necrotic lesions on leaves, leaves, and branches that are dying back?

Are the seedlings dying and the stems are girdled or rotted at soil line?

Are there any water-soaked lesions on stems that may have hairy appearance due to the presence of fungal spores?

Are the leaves pale on their upper side and are there any dusty blisters on the undersides?

Do the plants wither, stems are bending and collapsing?

Are the leaves curled and yellow?

Are the amaranth flowers discolored and deformed?

These symptoms indicate a fungal disease - Anthracnose. Avoid stressing plants by providing them with adequate irrigation and fertilization. Avoid damaging plants and creating wounds for pathogens to enter. Prune out dead or dying limbs to reduce levels of disease inoculum.

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.

Wet rot (also known as Choanephora rot) causes these lesions. The disease may cause the loss of leaves. Fungus mainly attacks plants that have been damaged by insects or by mechanical means. Plant only certified seed from a reputable nursery. Do not plant crops too densely. Treat the disease with copper fungicides if it emerges.

Likely cause for these symptoms is a fungal disease - Rust. Provide good air circulation around plants by thining them. Avoid making leaves wet when watering. All infected leaves should be removed. Spray leaves with sulfur early in the season to prevent rust or to treat mild infections.

Adult pigweed weevil feed on foliage and its larvae hollow out stems causing plants to wither. Uproot and destroy infested plants to limit the weevil population.

Aphids cause curled and yellow leaves. They 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.

Discolored and deformed flowers are caused by Aster yellows disease. This disease is usually transferred by aphids. There is no cure for Aster yellows, so the affected plants should be destroyed. Prevent the disease by controlling aphids. Spray the plants with the insecticidal soap 3 times, once every 3 days.

Amaranth is susceptible to several kinds of root rot. If your plant shows signs of decaying roots, root rot may be a possibility. Choose well-drained sites when planting. Add organic matter to improve soil drainage. Remove and discard infected plants and the surrounding soil.