Follow these Five Steps to increase your odds of growing quality tomato plants this spring and summer. 

  1. Diagnose the Problem Correctly
    Before you can treat any disorder, you have to identify
    the problem correctly. Photographs may help you diagnose tomato
    diseases. However, it may be wise to test a sample
    for an accurate diagnosis. You can bring a sample to
    the Pike County Purdue Extension office or
    you can send a sample to the Purdue Plant and Pest
    Diagnostic Laboratory.
    Instructions on how to prepare and send a sample may
    be found on the Purdue Plant and Pest Diagnostic
    Laboratory website, www.ppdl.purdue.edu
  2. Plant Resistant Varieties
    Whenever possible, choose varieties that have
    resistance to diseases. For example, tomato varieties
    are available that are resistant to Verticillium wilt,
    Fusarium wilt, and root-knot nematode — thus, the
    letters VFN are often associated with tomato varieties
    that have such resistances. There are no other practical
    means of controlling these diseases except for resistant
    varieties.
  3. Practice Crop Rotation, Fall Tillage, & Sanitation
    Whenever possible, do not plant tomatoes in the same
    place year after year. Many pathogens, such as the ones
    that cause early blight, survive from year to year in
    crop debris. 
    If it is not possible to rotate to a different plot of
    ground each year, remove tomato plants from the
    garden as soon as you complete harvest. 
    Use clean stakes or cages each year. 
  4. Maintain Plant Vigor
    Tomatoes planted in welltilled, well-drained, and properly fertilized soil, will
    be less prone to early blight and Septoria infection.
    They grow best
    in a slightly acidic soil, pH 6.2 to 6.8. Water stress usually preceeds blossom-end rot and
    can make plants more susceptible to early blight and
    Septoria leaf spot infection. At midseason, full-grown
    tomato plants require about 1 inch of water a week.
    Add water gradually and allow it to soak into the
    soil. Avoid overhead irrigations, which can lead to
    an increase in foliar diseases. 
  5. Use Fungicides as Needed
    Regardless of the efforts to prevent disease, many
    tomato gardens will have sufficient foliar disease to
    compromise yield or fruit quality.
    If you decide to apply fungicides, the following checklist might be
    helpful:
    • Be safe. Before you purchase a fungicide, check the
    label to be sure that it will control the diseases your
    plants have, and that it is safe to use on tomatoes.
    By law, all fungicide labels are required to list such
    information. Use the rate on the label and always
    wear the proper protective wear.
    • Use a pressure sprayer for best results. Compared
    to dusting plants, mixing fungicides with water and
    applying them with a pressure sprayer allows much
    better coverage and distribution of the fungicide on
    the plant.
    • Apply fungicides before disease symptoms occur or
    in the early stages of the disease. These applications
    will be more effective than applications made after
    the disease is well along. Begin sprays when plants
    approach 10 to 12 inches tall and continue spraying
    at 7- to 14-day intervals throughout the season,
    especially if disease has been severe in recent years.

Below are just a few of the common issues we see with tomato plants throughout the growing season. 

This info came from Purdue's publication BP-184, written by Dan Egel.
Please contact Sarah with any questions you may have. sspeedy@purdue.edu

Infectious Diseases

Early Blight early-blight.png
Septoria Leaf Spot septoria-leaf-spot.jpg
Fusarium Wilt and Verticillium Wilt fusarium.jpg
Bacterial Spot and Bacterial Speck  bacterial-spot.png
Root-knot Nematode root-knot.jpg

Nonifectious Disorders

Blossom-end Rot blossom-end-rot.png
Catfacing catfacing.png
Herbicide Injury herbicide.jpg