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Dahlia Query Again!!

Kitty52Kitty52 Posts: 184
I very kindly got good advice last year on dahlia tubers which I had planted for the first time. After storing over winter I have a few weeks ago planted them in pots in an unheated greenhouse.  I watered them when I planted them but we have had some 'warm' days over the past few weeks. Last year I didn't water them at all after planting following advice here but I can see that the compost is very dry even at the bottom.  My question is should I give some water or just leave well alone.  Or move out the greenhouse and put into a shed instead. Thanks.


  • FireFire Posts: 17,318
    edited April 2022
    There are different approaches to this. Some say no water at all, some say just a little. I don't know if it makes a difference until the proper green appears.

    What experience did you have with the growing plant last year? Mine are currently in slightly damp compost - damping the medium a very little, not the tuber.

  • Hostafan1Hostafan1 Posts: 34,536
    I plant mine in barely damp compost and don't water until there's a good couple of inches of growth and I can just see roots at the bottom of the pot.
  • Kitty52Kitty52 Posts: 184
    I had good dahlias last year Fire. Agree I have watched several videos and it does vary.  I certainly didn't water them last year but feel the compost appears so much drier because we've had mild temperatures and sun!! I did plant them in dampish compost. I may just leave well alone. Thanks for advice. 
  • KeenOnGreenKeenOnGreen Posts: 1,819
    Ours are in pots in an unheated greenhouse. We are in London, so we've had lots of warm days over the past couple of months.

    It can get very warm in greenhouses, even on warm Jan/Feb days, so I usually end up giving mine water during these months, but only a tiny trickle a couple of times per month, to stop the tubers drying out.

    I start giving them more regular water, about twice a week, about the beginning of March. I have slowly increased this over the past fortnight, and am now giving them a thorough watering a couple of times per week. Mine are already just starting to show shoots, and that is normally when I start giving them a liquid feed once a week.

    I won't put the pots outside until May/June, hardening them off over a 2 week period.
  • B3B3 Posts: 26,421
    The one I spent the most money on has done nothing so far. I'm trying to be patient.
    The cheapos  are well into leaf.
    In London. Keen but lazy.
  • Kitty52Kitty52 Posts: 184
    Very mixed comments re watering.  I am in Scotland so a few weeks behind you anyway KenOnGreen. B3 - mine were very slow last year in starting off and I had to look back to see it was NannyBeach who suggested putting them back into darkness for 10 days or so. That's where they'll be going shortly I think as that worked last year! B3 I have one or two which I grew from Gardners World seed which were spectacular last year compared to bought ones. All a mystery until they decide themselves. 
  • B3B3 Posts: 26,421
    Well, if it doesn't grow, it was going to be a horrible mislabelled snot green dinnerplate.Well that's what I tell myself.
    In London. Keen but lazy.
  • WoottieWoottie Posts: 10
    I keep compost moist. I have found that light plus moisture is the trigger to encourage them out of dormancy.  They will still shoot without moisture but much later.  
  • Dirty HarryDirty Harry Posts: 1,047
    I don't water initially any more, only once there's some decent growth.

    One thing to be weary of is how wet the compost could be at depth even if the top inch or so is dry.
  • Kitty52Kitty52 Posts: 184
    Varying advice!! Dirty Harry, the compost was dry at depth which was why I was concerned so have given a bit of water but not that much.  
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