• slide
  • slide
  • slide
  • slide
  • slide
  • slide
  • slide

Heat Related Tomato Disorders; Yellow Shoulders and White Cores

If your tomato harvest wasn’t up to par this season, you can blame it on the weather. High temperatures can prevent fruit set, delay ripening and impact fruit quality.

When temperatures soar to above 90 during the day and stay above 70 at night, tomato plants suffer producing fewer flowers and setting less fruit.

Even after the fruit is set high temperatures can slow ripening.  Tomatoes ripen most quickly when the temperatures are between 68 and 77 degrees.

High temperatures also cause fruit with yellow shoulders and white cores. Excessive heat prevents the production of lycopene, the red pigment in tomatoes resulting in yellow shoulders.

We can’t change the weather, but maintaining ample foliage on the plants, providing ample moisture and fertilizing properly will help reduce the risk of these disorders.

A bit more information: Harvest yellow shouldered tomatoes when the bottom portion is ripe. Cut off the tougher yellow portion and toss it in the compost pile. Do the same with those with white cores. Cut out the white tasteless portion and use the rest. Missouri Botanical Gardens has more information on tomato diseases and hot weather related problems. A tough white core in the center of the fruit may also occur under these stressful conditions.

Upcoming Live Events
& Webinars


Feb. 28, 2024
FREE WEBINAR

Create a Beautiful Landscape Free of Invasive Plants in Wisconsin Gardens
Register now

Feb. 29, 2024
FREE WEBINAR

How to Plan Your Rain Garden
Register now

March 6, 2024
FREE WEBINAR

Growing Summer Bulbs in Containers
Register now

March 7, 2024
Wauwatosa Public Library

Wauwatosa, WI

March 13, 2024
FREE WEBINAR

Hydrangea Selection, Pruning & Care
Register now

March 14, 2024
FREE WEBINAR

How to Select Rain Garden Plants
Register now


March 20, 2024
FREE WEBINAR

Maximize the Beauty and Enjoyment
in Any Small Space
Register now

March 23, 2024

REALTORS Home & Garden Show
West Allis, WI

March 27, 2024
FREE WEBINAR

How to Start a Garden for Beginners
Register now

April 3, 2024
Franklin Public Library

Franklin, WI

April 10, 2024
FREE WEBINAR

Container Gardening Throughout the Year
Register now

April 11, 2024
FREE WEBINAR

7 Steps to Managing Water Where it Falls in Your Yard
Register now

April 20, 2024
Pasquesi Home & Gardens
Lake Bluff, IL

April 27, 2024
Ridges & Rivers Book Festival
Viroqua, WI

April 28, 2024
Ebert's Greenhouse Village
Ixonia, WI

May 1, 2024
FREE WEBINAR

Ornamental Fruits and Vegetables
Register now

WATCH ON-DEMAND WEBINARS

Learn More

Book an Appearance

Learn More

Enter to win Longfield Gardens bulbs valued at $157.00 !

ENTER NOW