Dahlias

I don't have enough privileges to post in the correct forum so hopefully this post will be allowed here.

I have lifted and partially cleaned my dahlias, for frost free I have currently stored in my shed. The tubers are this years so should I split them or leave as is?
Once they have dried out I reckon the shed and `plastic` greenhouse are not suitable for over wintering (frost), I have a utility room that is unheated but frost free so ideal for storing, however I don't have space to lay out in trays and peat.
What would be best to wrap them up to store as I basically need to stuff them in to a corner (6 x 30 inches) until spring time.

Thanks

 

I have Dahlia corms which are over 25 years old so hopefully my advice is correct.
I lifted mine and cut the stems down to about 3 to 4 inches about a month ago, then stored them upside down on their stems for about a fortnight in a frost free place until the soil on them was dryish. I then brush off as much soil as I can being careful not to damage the skins of the corms. Best to leave a bit of soil rather than scrape the corms. Check there are no damaged soft corms, if so cut off and discard (1 bad apple and all that).
Then store in a frost free place in cardboard boxes. No peat and definitely not wrapped up. You want air circulation. Top of a wardrobe is good if bedroom not too warm or the likes of a shelf in a garage. I literally have dozens of corms now and indeed have offered to give some away if somebody would like some of them if they pay the postage.
If you want to split them I personally do this in the Spring once I have started them off again so that I can see that their have growing points on each portion I wish to split. If they are only small I wouldn't split to be honest. It's a good idea to check the corms in say February to see if any of the corms have rotted and cut them off if they have. I usually soak my corms for about 24 hours before starting them again.
I too live in Scotland so unfortunately we cannot leave Dahlia corms to over winter in the soil...well not unless you live right by the coast and garden on basically sand, then you might just get away with it, I have known of someone who had these conditions and their corms survived for quite a few years in situ!

 

Thanks for info silu, I have a spare bedroom that I keep the heating low at frost free so that would be ideal. I had never though of putting them on top of wardrobe in a box.

 

You are more than welcome @Scudo . My late Father used to put his Dahlias in boxes on top of a double wardrobe much to my Mum's annoyance as the wardrobe was in their bedroom! She was always convinced creepy crawlies lurked in amongst the corms, she was NOT a gardener!

 

Looks like I have lost most of them :-(
I cleaned them up and thought will store in the shed until they dry off and then store in a cool place in house.
Went back after a week and most were covered in mould :-(
I will salvage what I can and hope for the best come spring.

 

@Scudo
I wouldn't worry too much about surface mould. So long as the tubers are firm to the touch they should be ok, just clean up and dust with flowers of sulphur then store dry and frost free.
Dahlia tubers need to have a stem if they are going to grow next year; as the base of the stem has the dormant buds on it. So split them after they start into growth next year, or you can take cuttings then.

 

@NigelJ , @silu I find it difficult to know exactly what does what on a Dahlia tuber. You mentioned they need a "stem " . Found this photo on Google , the stem or stalk is where the growth starts ? I cut my old flower stems back after lifting to about 2" , similar too the 2nd photo.

 

You done good Harry! Hard part is waiting for mid spring (and making sure you labelled them properly!)! Earth em up a bit, wait till you see growth and you can cut them with a sharp knife down the stem providing there's growth buds on each bit of stem your cutting and a tuber attached! You get a few plants for the price of one

 

Hi @HarryS
That's a healthy looking corm! I would keep an eye on the furthest to the right bit of the corm. It looks as tho that tuber is damaged? If they do get damaged when being lifted they can then rot off and infect the next door tuber etc etc.You might be best to trace back and cut it off where it joins if this makes any sense at all. I'd also try and gently brush off a bit more soil once the soil is dry.
The other photo you have put up shows really well where the next year growing points are. The stems you have cut off isn't where the new growing points are located. If you cut the stems right down or worse just broke them off the chances are that you could damage/remove the next season's buds.
I leave about 2 to 3 inches of stem on when putting the corms into storage. Find the stems quite good "handles" to carry the corms about. Once the buds are evident and starting to break the next season I then usually cut off the previous seasons stems back further as I can easily avoid the new buds and the old stems can be places where dreaded earwigs can hide.

 

I have cleaned them up and ordered sulphur from ebay.

 

Hi @Scudo,
I have spare flowers of sulphur (about 3/4 of a container of it) I don't use it anymore as not needed to however if you live close to me (I live 12 miles South of Perth you are more than welcome to it. Just PM me and I'll see if I can find it.
Perhaps the problem was not enough air circulation or did they get frosted? It was very cold for a few days a couple of weeks ago. I still had some fairly healthy looking Peppers in my unheated greenhouse. Post the cold spell they had definitely got frosted inside the greenhouse. Normally it takes quite a few months for Dahlia corms to rot and yet it's not even Christmas yet.
If your corms have rotted I can give you some of my medium (height and flower sized) red Dahlia corm if they would be of interest. I have FAR TOO MANY these days and my surplus need a good home to go to.
your remaining ones are ok. Update! Found the flowers of sulpher. Not that much left in the container, thought there was more than there is. If you live really close to me you are still welcome to it but otherwise a waste of your time.

 

No these were just Google photos . Although mine do look pretty similar . Anyway I have a learnt quite a bit more on Dahlia tubers from Linz and yourself I always think Dahlia tubers look like they have been designed by a committee , complicated things

 

I have already ordered some sulphur via ebay but thanks for the offer.
I dont live near to Perth but would it be possible to send a few corms if I pay the postage, it would cost around £2.63 using parcel2go, gladly send you £5 to cover, paypal or cheque.

 

Hi @Scudo I very much doubt I could send my corms for that kind of money. Mine are at least the size of the 1 in the photo HarryS has put up. I reckon having had a quick look at parcels2go the least it would cost would be about £8 odd £s. As there is no rush if you would like to PM where you live there might be an occasion between now and next May when either I or husband/daughter might be travelling near you and delivery could be made some how?

 

I had another check on parcel2go.
Prices although subject to various permutations of size & weight.
Using Hermes drop off:
4.9 kilo £5.39, 1.9 kilo £3.72
I would of course pay whatever it costs.
I live in Bo'ness.

I use parcel2go quite a lot although mainly shoebox size and just under 2 kilo hence my original estimate.