Definition

• Black rot is a fungus that attacks plants.pot plants image by Crisps85 from Fotolia.com
  
  Black rot is a fungus that attacks the leaves of fruits and vegetable plants. Leaves will have brown or black colored spots, which will often begin small and grow in size and deepen in color. Black rot can occur at any stage of plant growth and will ultimately lead to the decay of the plant.
  
  

Cause

• Rainy weather exacerbates the problem.rain image by tomash from Fotolia.com
  
  Because black rot is a bacterial fungus, it thrives in humid, rainy conditions. These conditions, especially in hotter months, will cause the bacteria to multiply.
  
  Black rot affects the part of the plant that is above the soil, so insects can contribute to the problem by spreading it from plant to plant.
  
  

Prevention

• Remove weeds to prevent the spread of fungus.pulling weeds image by palms from Fotolia.com
  
  Removing infected foliage can help prevent the spread of black rot through the rest of the plant. Also, remove weeds from the area, as they can be carriers of the bacteria as well.
  
  Before planting, putting seeds in hot water may also kill bacteria before it has the chance to spread.
  
  

Treatment

• Grape vines are susceptible to black rot.grapes image by siloto from Fotolia.com
  
  Natural insecticides that include ingredients such as corn oil or garlic can help eliminate black rot. If black rot has occurred, be sure to rotate crops with other plants that are not susceptible to the fungus. Also, do not waterlog the plants as this can help the bacteria spread.
  
  

Plants

• Insecticide containing garlic can help treat black rot.garlic in the pigtail image by Maria Brzostowska from Fotolia.com
  
  Popular plants that are affected include grape vines, cranberries, apples and vegetable plants like cabbage.