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Splitting tomatoes

We have a small unheated greenhouse to grow tomatoes in grow bags. Up until now they have been very good and behaving themselves. I water and feed them regularly (feeding with Tomorite twice a week and water a few times a day). Now they are starting to show signs of splitting with juice oozing out. Some seem to be very pale as well. I will be getting a much bigger greenhouse next year with maybe a heater system. As the weather is getting colder at night could that be a problem or too much water?




  • Inconsistent watering. 
  • Pete.8Pete.8 Posts: 10,953
    edited September 2022
    It's due to varying amounts of water being available to the roots.
    This year has been tricky due to the extremes of heat.
    If there is insufficient water available at the roots, the fruits will not swell.
    Then they get watered and the fruits swell - and that's when the skin may split.

    The key is to keep the roots with just enough moisture to prevent sudden swelling of the fruits - not always easy.
    I always get some splits with mine in the greenhouse, but this year is the worst I can remember - but I've still had more tomatoes than I know what to do with.

    PS - Tomorite twice a week is a bit too much. Once a week (max) will be plenty especially if they're outside. In a greenhouse they will grow faster, so once a week when you have your new greenhouse will be good.

    Billericay - Essex

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • Thanks, they are in a greenhouse (not very good one, it was there when we bought the house a year ago). Will start feeding once a week from now on.

    Thanks a lot


    P.S. We have had loads of very good toms too
  • Actually I would stop feeding now @Meddyliol as there is only a month of growing time left in a cold greenhouse. I too had more splitting than usual,  but from what I have been told it's watering plus the skins setting that means the moisture has nowhere to go thus splitting the skins. This was caused by the heat I'm told.
    Slowing the watering down, I do it every three days now, stresses the plants into ripening the last fruit.
    If you are replacing your greenhouse,  go as big as you can, have two roof vents, and one opposite the door too if possible. 😁
  • Pete.8Pete.8 Posts: 10,953
    I agree - no point in using a fertilizer that encourages more flowers at this time of year.
    Mine had their last feed last week.

    Billericay - Essex

    Knowledge is knowing that a tomato is a fruit.
    Wisdom is not putting it in a fruit salad.
  • SlumSlum Posts: 382
    The wider variations between day and night temperatures can also cause splitting.
  • FairygirlFairygirl Posts: 53,996
    No need to feed so much - at any time  :)
    In hot weather, if the temps are well above mid 20s in your greenhouse, you need to ensure good ventilation, and add shading if you're in one of the hotter parts of the country, and getting long hot spells, especially if overnight temps remain high as well.

    I'm not sure why you were watering so many times a day either. Even if they're in pots or growbags,  rather than in the ground, they shouldn't need watered so often. It's better to soak properly, then wait until they're very slightly wilted before watering again. Having said that, some varieties can be more prone to splitting anyway  :)
    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • More likely its the colder nights that causing it
  • I was very late getting my tomatoes planted up so my fruit is only just beginning to ripen. I haven't had splitting skins but the skins have definitely been tougher this year. I have given up using Grobags, not enough depth for me and much more difficult to keep the watering correct. I use large pots standing in washing-up bowls as drip trays.
    I am thinking of removing the tarpaulin I put over the greenhouse as shading now the weather has cooled down. It is taking a battering with the strong winds at the moment. I only feed once a week and water as required, once or twice a week usually although this year has been different.
  • McRazzMcRazz Posts: 291
    I find that perfectly healthy, regularly watered Tom's can still split near the end of their lifecycle (i.e. end of Sep / early Oct).

    I'd always assumed it was to do with seed dispersion. 
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