The Accidental Smallholder Forum

Growing => Gardens => Topic started by: Anke on October 31, 2022, 08:26:50 pm

Title: Overwintering dahlia tubers
Post by: Anke on October 31, 2022, 08:26:50 pm
How do people overwinter their dahlia tubers in the North of the UK?


I did one lot successfully last year in paper sacks in the garage (bought originally as tubers), but am trying this year to overwinter my seed-sown dahlia tubers in pots inside the Keder (their tubers are not quite as substantial as my dahlias bought as tubers, I guess those are older plants already), with additional protection if needed later on (as opposed to just in paper sacks). How damp do I need to keep the soil in the pots? Anyone else do it this way?


BTW - dahlias grown from seed were a revelation! I choose open flowered varieities (like "Bishop's Children"), and they were so busy with all sorts, but mainly bumble bees! And such bright colours... but of couse you cannot do a planned colour co-ordinated garden with those...
Title: Re: Overwintering dahlia tubers
Post by: Rosemary on November 01, 2022, 08:26:29 am
Watching. I bought some dahlia tubers from Sarah Raven and they have been stunning this year. I'd really like to see them again next year.
Title: Re: Overwintering dahlia tubers
Post by: Fleecewife on November 01, 2022, 01:25:07 pm
I can only tell you what not to do  :D .  I dug mine up one year and spread them in a box, soil on them but not covered then kept them frost free.  By spring they had shrivelled up and gone rotten.
My conclusion is that they should be stored like carrots, cleaned of old soil - just brush it off - then stored in moist sand in a frost free place.  The TV gardeners keep them in soil in their lovely heated greenhouses then take cuttings when they sprout in spring.  Lesser mortals just plant them back outside after the frosts, perhaps if they sprout early then pot them up indoors.   I just grow new ones from seed each year as that is something I love to do.
Title: Re: Overwintering dahlia tubers
Post by: Anke on November 01, 2022, 04:07:04 pm
I plan to do more from seed next year, the ones I did this year were great, but the slugs got half of them... The best bit is that you don't know which colour they will be until they flower.


I agree the sand (or relastively dry soil) sounds the safest...


I bought tubers from Sarah Raven (yes I succumbed...) last year, and they did survive overwinter in paper sack inside garage inside metal feed bin (same as we store potatoes). I plant up into buckets in February though and then keep on heat mat in Keder until they start to sprout, then off heat still inside until beg of June. Haven't dared to divide yet...
Title: Re: Overwintering dahlia tubers
Post by: Anke on November 01, 2022, 04:08:31 pm
  I just grow new ones from seed each year as that is something I love to do.


Where do you buy your Dahlia seeds from?


I used Chiltern Seeds for almost all my flowers, incl Dahlias.
Title: Re: Overwintering dahlia tubers
Post by: Fleecewife on November 02, 2022, 04:48:01 pm
  I just grow new ones from seed each year as that is something I love to do.


Where do you buy your Dahlia seeds from?


I used Chiltern Seeds for almost all my flowers, incl Dahlias.

Just about everywhere that sells flower seeds will include Dahlias.  I think I got my Bishop's children from Mr Fothergill last year, or even the dreaded Thompson and Morgan, but it could have been from one of several (I don't like the big heavy headed dahlias, just the singles)
Title: Re: Overwintering dahlia tubers
Post by: Fleecewife on November 02, 2022, 04:52:38 pm



I bought tubers from Sarah Raven (yes I succumbed...)


 :o :o :o   Just the same as from elsewhere but twice the price  :innocent: :roflanim:
Title: Re: Overwintering dahlia tubers
Post by: Penninehillbilly on November 03, 2022, 06:10:16 pm
I kept mine in pots last year, leaving them to more or less dry out, luckily we do have a conservatory,  (aka dumping ground, not a posh one🤣)so they were tucked out of the way in there. Trouble is, I missed some in spring, looked a bit sad when I found them in summer, I bit of tic they recovered. I also popped some in soil in polybags, they did OK as well.
Garage sounds fine to me, if it's frost free.
Title: Re: Overwintering dahlia tubers
Post by: Anke on January 12, 2023, 08:22:55 am
Just to say.... the dahlias I left in dry soil in buckets inside my Keder greenhouse have gone soft, so rotten. I did put some into a paper bag and they are inside the vestibule and so far ok.

So now know what NOT to do, but we did have quite hard frost in early December....
Title: Re: Overwintering dahlia tubers
Post by: Penninehillbilly on January 18, 2023, 07:15:48 pm
i missed some pots outside  :'( :'( :'( .
i darent look in the shed where some were put as a temporary measure :-(.
Title: Re: Overwintering dahlia tubers
Post by: macgro7 on February 09, 2023, 07:06:06 am
My dahlias were left in the ground where they grew all summer long. After winter they grew back themselves - the coldest we had last year was around -6.
This year I sorted them out after the stems died after first frost (November). And again left all of them burried exactly where they were last year - only separated some of the tubers. This year was the coldest we have had for years, but still only -7

What where the temperatures in the north on Englan or Scotland? I assume colder than here in Leicester.
Title: Re: Overwintering dahlia tubers
Post by: Anke on February 09, 2023, 08:27:04 pm


What where the temperatures in the north on Englan or Scotland? I assume colder than here in Leicester.


Quite a bit below that, at least -10 in early December.


My leeks all went mushy too... which has not happened for quite a few years...