Grey Wall in Tomatoes

Grey Wall of Tomato


Grey wall or blotchy ripening is a name that is indicative of the disorder where fruit do not ripen properly or ripen unevenly. Symptoms develop whilst the fruit is still green. This condition is only found on the fruit and not on the plant.


Affected green fruit, have large, greyish or yellowish hard blotches on the fruit. Only when the fruit is over-ripe do these areas ripen – if they ripen at all. Ripe fruit have brown or green areas on the inside of the fruit walls. The outer walls of the fruit tend to be the most affected, which is obvious once the fruit are cut.

Symptoms often develop in the midst of plants which are dense and have lots of foliage and also on plants which are growing in compacted soils. Stressed and unhealthy plants also add to the problem.

A higher incidence of this condition is found in cool, wet, cloudy conditions. Because of these conditions, the fruit do not ripen properly and “veins” develop on the inside walls of the fruit. It is these areas that always remain dark green and seldom ripen. Some people also believe that the incidence is affected by the nitrogen : potassium ratio of the fertilizer program, however this is not yet substantiated.


Good growing conditions will help to prevent the problem. Ensure that plants receive adequate fertilizer and regular/even watering; and check that the soil is not compacted around the roots. Tomatoes should be grown where they receive full sun and are not heavily shaded.

Lucia (13 Posts)

Lucia Grimmer holds a Masters Degree in Plant Pathology and works as a technical nutrition specialist in the fertilizer industry. She has studied at many universities including those in the USA and has worked in a research capacity in both government and commercial organizations. She is author of several scientific papers and technical disease and nutrition manuals. Lucia has won several awards from farming magazines for her technical articles. Originally from Zimbabwe, Lucia and her husband owned a 1500 ha farm where they grew commercial and horticultural crops including tomatoes before they migrated to Australia. As a specialist in plant disease and nutrition, every day Lucia provides professional advice to commercial growers of tomatoes.

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3 Responses to “Grey Wall in Tomatoes”

  1. I have some grey wall tomatoes and i believeit is from our growing season this year. Very cold and not like past years. We did have a successful season despite this problem. My Super Marzano grew to eight feet tall.
    I have 21 pints of tomato sauce in the freezer.
    Thanks for the website

  2. Annette says:

    Thanks Beverly. A cold wet season is probably the answer. We’re having the same problem here in Queensland, Australia, due to the weeks of constant rain and extensive flooding. It’s awful.

    Good to see you still achieved large plants and were able to harvest enough to create sauce for the winter. Keep at it!

    Kind regards

    Annette Welsford

  3. Adrian Fisher says:

    I think a few of my plants have grey wall, so I was wondering what I should do i.e. remove the fruits that are affected or remove some leaves… ? My plants are crowded (my first year growing them), but even some of the fruit is in direct sun…If I leave them are they still edible?

    Thank you!

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