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Tomato seedlings gone pale green

I’ve got some 3 week old gardeners delight tomato seedlings that has gone quite light in colour - sort of lime green with a tinge of yellow.. this is very noticeable given they were bright green when they first germinated. Since germination I’ve put them on the window sill that gets the morning sun till 1pm.. I wonder if it could be due to the sun being too strong? (But won’t they go leggy if I didn’t put them somewhere sunny?) - technically it should be filtered light through the window and not direct sunlight.

Or could it be nutrient deficiency? But they’re still so young surely not? 

Here’s a picture:


  • FairygirlFairygirl west central ScotlandPosts: 47,194
    Those long leaves are just the seed leaves. Perfectly normal for those to yellow and die back. 
    Light is what they need,but not strong sun for hours. If you can find a more suitable window for them, that will help, but there isn't much to worry about - they've barely started growing. Just turn them each day too to keep them 'straight'   :)
    It's a place where beautiful isn't enough of a word....

  • celcius_kkwcelcius_kkw Posts: 732
    @Fairygirl Thank you.. that’s reassuring. I watched a YouTube video before and the guy in there showed his 3 week old seedling which seems way bigger than my 3 week old.. his already had two sets of true leaves... 

    Also.. with regards to pricking out.. I have sown them in root trainers so there’s limited space.. I don’t want to prick out just yet as they’re still quite tender but I do worry that their roots might get tangled up later on.. 
  • FairygirlFairygirl west central ScotlandPosts: 47,194
    Bit early to consider pricking them out. They're only just starting to grow. They don't all germinate and grow at the same rate, so don't worry. They're actually quite easy to disentangle too  :)
    Wait until the roots are poking out the bottom, or, as they're in those trainers - just wait till they look quite full, and do that each time you pot on. The final pot you're using, and where you're putting them etc, will determine how often you do that.
    If they're going in the ground, it's a case of waiting until they're big enough and conditions are suitable if they're going outdoors.  :)
    It's a place where beautiful isn't enough of a word....

  • SkandiSkandi Northern DenmarkPosts: 1,510
    They look like they need more light not less to me. especially those at the back of the photo, they are elongated and reaching for light. I would put them outside during the day if it is not windy/cold start in shade and after a couple of days they will be ok in full sun. I spend a lot of time doing the plant pot shuffle in and out at this time of year.
  • celcius_kkwcelcius_kkw Posts: 732
    @Fairygirl @Skandi Thank you both.. at the moment they’re getting at least six hours of morning sun.. I think I will just need a bit more patience for now.. glad to know that they’re not sick. 

    By the way, one more question.. I may have accidentally sown two seeds into the same hole and now some have two sprouts immediately adjacent to each other.. should I chop one off? Would it be possible to tease them apart if they’re too close together?

  • FairygirlFairygirl west central ScotlandPosts: 47,194
    It can be quite hard to get them apart, but you could just remove one  :)

    When you do pot them on, just bury them right up to the first set of leaves. That helps them develop more roots to anchor them.
    I wouldn't put those outside just now, even if the weather's benign. They've only just germinated and started growing. Give them a chance  ;)
    It's a place where beautiful isn't enough of a word....

  • LynLyn DevonPosts: 20,593
    You will be able to leave them in the compost they’re  in until much bigger, they’re in root trainers, the roots don’t come out of the bottom in those, and can stay in there until they’ve got to about 5” tall..or about 3 or 4 pairs of leaves.
    Just pull out the smaller of the two seedlings. 

    Gardening on the wild, windy west side of Dartmoor. 

  • celcius_kkwcelcius_kkw Posts: 732
    edited May 2020
    @Lyn I’m hoping to preserve both seedlings in each cell.. if possible some of the cells have not produced any seedlings at all.. I sort of want to have an insurance just in case.. I’m planning to let them grow bigger like @Fairygirl said and then try my best to separate/tease them apart so I can make the most of whatever I have.. 

    On a different note, have either of you grown tumbling bella before? (Supposedly an improved version of tumbling Tom) .. I have only had two seedlings from 10 seeds.. that seems like an incredibly poor germination rate..? (Compared to sweet aperitif and gardeners delight that have germination rate of over 80%)
  • If you've germinated more than you need I would not bother pricking them out. I would pull the weaker looking plants and discard them and pop the soil plugs directly into a larger pot to let the roots develop before siting them in their final place. If you elect to prick them out be super careful, if the roots from a neighbour are entwined you may damage the baby roots and retard the growth cycle slightly.
  • celcius_kkwcelcius_kkw Posts: 732
    @Guillaume B Thank you.. It’s been a couple of weeks since I posted and I’ve now already pricked out all of them.. it was surprisingly uncomplicated.. the long tap root seemed pretty strong and undisturbed as I separates them. Some of the seedlings are noticeably weaker than others though.. I’m giving each of them a container of its own now.. I wonder if the weak seedlings will ever grow well in the future( or perhaps they’ve just had a weak start in life) 
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