Leucocoprinus birnbaumii, also known as Lepiota lutea, are mushrooms that surprise indoor gardeners when they suddenly and mysteriously pop up in houseplants. Although the odd-looking fungus is often unwelcome, these mushrooms generally aren't harmful to your plants. The mushrooms are familiarly known as flowerpot parasols, yellow parasols or yellow pleated parasols.

Characteristics

Leucocoprinus birnbaumii mushrooms emerge as oval shapes, turning bell-shaped and then becoming somewhat flat as the mushrooms age. Colors of the mushrooms vary from white or creamy yellow to bright yellow, with yellowish gills. The surface is smooth and dry, but may develop a scaly or powdery appearance as the mushroom matures. The slender stems are usually between 1 and 3 inches long. The mushrooms most often appear in clusters, but a single mushroom isn't unusual.

Habitat

Mushrooms thrive in rich soil and warm, humid conditions, including home landscapes and natural, forested areas. They are especially common in warm, tropical areas, growing year round in lawns and gardens of the southern United States. In cooler climates, the mushrooms are common outdoors only during the summer months. Indoors, houseplants growing in warm, organically rich potting mixture are an ideal habitat for the mushrooms. While mushroom spores may float through the air and land in your houseplant pot, it is more likely that the spores were hiding in the potting mixture.

Removal

Leucocoprinus birnbaumii mushrooms are nearly impossible to remove, and even fungicides are of little use. Sometimes removing all the soil in the pot and replacing it with fresh potting mixture may work, but even then, the mushrooms may reappear. The best way to cope with the mushrooms is to pull them by hand and discard them safely as soon as they appear.

Considerations