Tomato: White mold

categories: Tomato Tomato Diseases Vegetables

revision date: 2022-12-07 12:00

Interior stem showing white fungal growth and black sclerotia.
Interior stem showing white fungal growth and black sclerotia
Photo by: R.S. Byther

Biology

White mold is caused by a fungus. It typically attacks dead flower petals or dead leaves, then spreads into living tissues. The infection often starts in branch crotches or at the base of stems. Initial symptoms may include a rapidly spreading soft rot. Affected tissues turn gray and may be covered with a mass of cottony, white fungal growth. Hard, black fungal structures (measuring 1⁄4″ to 1″) are often produced on the cottony growth and inside the affected stems. Infected stems may be tan, then eventually turn a bleached, bone-like white. Disease development is favored by long periods of cool, wet weather.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

  • Plant in well-drained soils.
  • Avoid overhead irrigation.
  • Space plantings to improve air circulation, particularly around the base of the plants.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

  • None recommended