Posted on 19 August 2008 by

Yellow Shoulders on Tomatoes

By Michelle Fabio

Do your tomatoes have yellow or green shoulders?

That is, when the tops simply refuse to ripen to a glorious red color and instead stay yellow or green?

Bill Lamont, a professor and extension vegetable specialist with Penn State University’s Department of Horticulture, says that if your tomatoes have yellow shoulders, intense heat or light has probably prevented lycopene production, and there are several things you can do to help your tomatoes get red shoulders next time around.

What can you do to avoid yellow shoulders? Lamont suggests the following:

(1) Select varieties of tomatoes that are less prone to yellow shoulder, e.g., cherry tomatoes.

(2) Pick tomatoes at the “breaker stage” when you first see pink color and let the fruit ripen at room temperature.

(3) Be sure your plants get enough potassium fertilization.

(4) Make certain your plants have enough leaf cover so that ripening tomatoes are shielded from intense heat and light.

Have you had a problem with yellow shoulders? What have you done to combat it?

Source: Wrapping your head around tomatoes’ ‘yellow shoulders’

2 Responses to “Yellow Shoulders on Tomatoes”

  1. Anthony Says:

    I’ve heard that amending the soil with epsom salts is great for a boost of potassium. Do you have a opinion on this? I’m thinking about trying it next season.

  2. michelle Says:

    Hi Anthony, I’ve seen Epsom salts discussed regarding magnesium; I found a great discussion of it here:

    Fertilize with Epsom Salts

    The part specifically about tomatoes is all the way at the end.

    Please let us know if you try it!

    Any other readers use Epsom salts?

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