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At A Loss With Dahlia Tubers

Kitty52Kitty52 Posts: 184
I am despairing about my dahlia tubers.  Tried keeping them in the dark again but only a couple have just started to appear last week and don't seem to be progressing much further since bringing them into the light. Should I bring them into the house and try and force them more with some warmth or still just be patient.  I have started giving just a trickle of water.  I have a couple that I grew from seed last year and just left in the garden over winter and they are starting to sprout quite happily.  Some of the ones still reluctant to come out of dormancy are ones I grew from seed but also tubers I had bought last year. They are in an unheated greenhouse. The joys of gardening!!!


  • punkdocpunkdoc Posts: 14,379
    How long have they been planted?
    How cold has it been where you are? They will not start to grow until it warms up a bit.

    My tubers went into a cold g/h in mid April and have only been growing for about a week.
    How can you lie there and think of England
    When you don't even know who's in the team

    S.Yorkshire/Derbyshire border
  • Kitty52Kitty52 Posts: 184
    Thanks. I am in Scotland so maybe still bit cold in greenhouse 24 hours. I think I did mine about beginning of April.  The ones that have started seem to have come to a standstill. Just one tiny sprout which hasn't seem to have got any bigger. I will just leave well alone then and hope for the best.
  • JennyJJennyJ Posts: 9,646
    My dahlias that were left in the ground and some in pots outside appeared at the beginning of May and now have about 3 to 6-inch shoots, but I'd expect everything to be later in Scotland.
    Doncaster, South Yorkshire. Soil type: sandy, well-drained
  • BiljeBilje Posts: 756
    I pot up about 50 dahliatubers…I know I know it’s daft but they just keep multiplying. Anyway most have been potted since March…in cold greenhouse…cold frame and outdoors. I’m in NE England.
    its warmth that prompts them to grow. I’ve never kept them in the dark once potted. The greenhouse ones were4-5inches high and are getting planted in borders. The cold frame ones are about 2 inches high and the ones that stood against the house wall are just shooting. I’ve always kept them all watered but not soggy. If kept in the dark and dry it’s just storage..just my opinion. Good luck with them I’m sure they’ll respond. 
  • FairygirlFairygirl Posts: 54,023
    I bring mine into the house to start them here. Then they go into the little greenhouse when they're a decent size, inside another clear plastic box, and go out on nice days until the weather's consistent enough for them to be outdoors all the time.
    The extra box is so that they're warm enough overnight. My growhouse is the same temp at night as it is outside, until about May, although the last two Aprils have been warmer, so it's been a bit easier. Not enough windowsills for everything  ;)
    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • Kitty52Kitty52 Posts: 184
    Thanks for all the comments.  Its lovely here today so hopefully this warmth will give them a spur on. I'll talk to them nicely!!
  • RoddersUKRoddersUK Posts: 536
    2 of mine have started to grow, one is doing absolutely nothing. Had them in the house on a window seal for over a month.
    Tubers are not rotten, guess it needs more time for some reason.
  • ObelixxObelixx Posts: 29,654
    They seem to grow at their own pace depending on variety.

    I left all my dahlias in the ground last autumn except for two young plants I had in pots and which I over-wintered in the polytunnel.  I also was given 3 huge tubers at a recent garden club meeting and these had been lifted, cleaned and over-wintered in a shed.

    The ones outside in the ground are now anything from 2" to 8" high with some not showing at all.  The no-shows are either late or dead.  The two in pots in the polytunnel are 12" and 18" high with fat flower buds.   The 3 bare tubers have been watered and sat in a tray.  They vary from teeny buttons of shoots just showing to a nice clump of foliage about 4" high so that one will be planted out this weekend.
    Vendée - 20kms from Atlantic coast.
    "We don't stop playing because we grow old; we grow old because we stop playing." - George Bernard Shaw
  • Allotment BoyAllotment Boy Posts: 6,435
    Make sure there are no slugs that can get at them. I  have left Dahlias in the ground a few times, one year nothing came up,  thinking they had rotted I dug them up, slugs had eaten off all the young shoots till there was nothing left to sprout. When I dig them up now I  clean very carefully and put slug pellets round.
    AB Still learning

  • Kitty52Kitty52 Posts: 184
    Oh thanks. Def no slugs in greenhouse. I have just left one dahlia in the ground to see what would happen. My first time growing dahlias and was a seed grown one. My concern was the ones I had in pots waiting!!!
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