How to Treat Problems With Staghorn Ferns
- 1). Check the sunlight. Staghorn ferns should not get direct sunlight. The best light is bright but indirect. Morning sun can be tolerated for a few hours. Move the staghorn to an area with better lighting if it is browning or yellowing out.
- 2). Let the plant dry between waterings. Staghorn ferns should become completely dry -- all the way through -- between waterings. A common cause of rot and losing leaves is overwatering. Signs include black spots on the guard leaves that can spread rapidly and kill the plant. This is a fungus called rhizoctonia (see Reference 1). Apply a fungicide or let the plant dry out completely and water moderately until the spots disappear.
- 3). Water with distilled water. Use tap water if it has a low salt content. Softened water will cause old leaves to brown out quickly and can even kill the plant. To get rid of salt water, completely soak and drain with distilled water.
- 4). Check for insects. In some areas, spider mites can cause leaves to brown out and die early. Spider mites are tiny -- about the size of the period at the end of this sentence. To check for spider mites, shake the plant or leaves over a white sheet of paper. The tiny little mites will fall onto the paper. Use a magnifying glass to spot them, or look for tiny dots that are moving across the paper. Spider mites can be treated with oil insecticides -- some horticulturists say not to use oils on staghorns, so check with your local distributor for information on the best insecticide to use.
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