What Is Wrong With My Fern?

Do leaves have water-soaked spots on them?

Are there any small, dark green spots formed at the base of fronds; spots may turn brown to black as they enlarge?

Are the roots dark brown, the plant is wilting, yellowing, and dying?

Have the brown, irregularly shaped spots formed on the foliage close to the crown?

Does the root have swollen galls, the foliage is gray and wilted?

Water-soaked spots on fern leaves are caused by bacterial blight. The copper spray will help in reducing the spread of the disease. If there are no new pods on the plant, you should remove the diseased plants.

These symptoms indicate Foliar nematodes. These microscopic roundworms overwinter in soil or plant debris, then travel up a plant's stem in the film of water created by spring rains. Remove and destroy infested plants and the surrounding soil and do not compost the debris. Rotate plantings and mulch in spring to keep nematodes from climbing up plants. Avoid wetting leaves when watering.

These symptoms indicate a fungal disease - Pythium Root Rot. Do not overwater plants. Remove affected plants and their roots, and discard surrounding soil. Plant only in the pasteurized soil. Hold back on fertilizing too. Keep hose ends off the ground. Apply a copper-based fungicide to protect plants.

Rhizoctonia blight is a fungal disease that can infect ferns. Brown, irregularly shaped spots form on the foliage close to the crown or sometimes at the top. Spots spread very rapidly. The webbing of the fungus forms from frond to frond. Rhizoctonia blight can be treated with a copper-based fungicide. Plant in pathogen-free pasteurized potting mix.

Gray, wilted plants and roots that have swollen galls indicate root-knot nematodes. Prevent root-knot nematodes by applying chitin or introducing parasitic nematodes to the soil before planting. Solarizing the soil also helps in preventing root-knot nematodes.

Over-fertilization may cause fronds to have many lobes and indentations, also tips of fronds and leaflets may turn brown and die. Reduce the amount of fertilizer being used and leach the pots if you're growing it in containers.