Producing your own seed spuds from mini tubers, cuttings, etc.

@pete These are tubers from last year's sterilized rooted shoots - not a sign of scab. And the tubers the shoots were taken from were covered in scab as badly as those in post #11 above.

 

Time to take some cuttings. The tubers planted in damp MPC have sprouted well under growlights. From https://www.researchgate.net/publication/329371871_USING_STEM_TIP_CUTTINGS_IN_POTATO_PRODUCTION it appears 150mm long is the correct length and rooting hormone is essential (hope mine isn't too out of date).

 

Interesting experiment @Scrungee

I hear of people doing kitchen-table-top Tissue Culture these days, so there is always that . When I worked on a tissue culture nursery and they had a greenhouse for "mother plants" at some ridiculously hot temperature, above the point at which the virus would reproduce, such that growth made on the plant would have a virus-free meristem ... just chop that out (under microscope) and away you go ... the flaw with this was that at a temperature that the Virus would not reproduce the plant didn't want to grow either!

On a somewhat unrelated note:

I normally grow 4 or 5 Bags of Spuds for "earliest harvest". But they take up quite a bit of space, and once they have some foliage moving them from Conservatory to Greenhouse, when cold greenhouse is warm enough, and then Greenhouse to Outside, when i need the greenhouse space, is "fraught".

Now I've got a bigger greenhouse I have thought it differently as I have room for one bed of Early Spuds in the greenhouse. So instead of bags I grew some in Pots to plant out, so when the Spuds were set for Chitting in February-ish I put some tiddlers into 9cm and some slightly bigger into 1L, and then when I planted out the spuds a few weeks ago I planted the potted ones at the end of the row, and the chitted next ... then the next variety ... so that I would just harvest from "end of row" as normal.

I wonder if "potted" might even be a better flying-start than plant-in-bag, as easy to have a few small pots in warm "germinating" room, or even under lights!, and then plant them into Bags when they are ready.

 

12 x 1L pots planted with 2x cuttings in each in 50:50 silver sand/MPC and covered with upper 2/3 of 2L PET bottles.

Cuttings were cut through lower solid part of stems as close to the infected tubers as I dared, and I still sterilized the stems.

I've cut the tops off the longer stems to make them produce side shoots and will produce another batch of cuttings from those. Luckily I bought 2 sacks of silver sand from Homebase reduced from £5 to 50p.

And I've still got this second tray of more stocky, branching, sprouting tubers

 

You're the only person I know who finds those 90% off deals ...

 

Dammit! It was actually only 89% off, at least I ignored Mrs Scrungee questioning why I needed more than 1 and bought 2.

 

I might have overdone the sterilization a bit by leaving them in the solution for too long, causing what is a bleach solution to be taken up into the stems (a topical cure for disease at the moment).

They started looking sick and lost half their leaves, but 17 out of 24 cuttings have taken and roots are showing through the bottom of the pots.

They were kept in slight shade (on a table inside my glazed garage doors) to prevent them being frazzled, but I'll now move them into a polytunnel to get more light.




But I got 100% success using rooted shoots pulled off infected tubers and soaked in sterilizing solution




These may all look rather small compared to some others potato plants in May, but these are to produce disease free seed potatoes for next year, probably only one small tuber per plant.

 

I seem to remember stem cuttings will always free root problems like scab.
Do you really need to sterelize them?

 

Probably not, but I went for a belt and braces approach (being preoccupied with sanitising everything at the moment). If they'd failed, I still had lots more stems for new cuttings. Next year I might try cuttings with and without sterilization.

 

Taken a week ago, now divided between 2 tunnels. Should produce enough small tubers to produce some seed spuds in 2021, to grow some big spuds with in 2022. DIY seed potatoes is bit of a long game

 

@pete How big did your cutting(s) grow? Some of mine are now approaching 4 feet long, which has surprised me because I didn't think they'd be so vigorous without the energy reserves in a tuber to support them.

 

I've actually tried another two cuttings this year, guess I've got too much time on my hands.
Did take them a bit late though and from pink fir apple.

I cant help thinking your spuds are getting so tall because you have them in the tunnel?
I've never grown spuds under glass/ polythene, only outdoors where the stay much shorter as most plants do.

 

I sorted out my daughter's garden earlier this year and planted Picasso & Kennebec maincrop spuds in open ground, then a row of courgettes 5 feet away, and also gave her some Salad Blue and Mayan Rose spuds in 15L tubs that were placed on the edge of a open paved area which was supposed to be mainly for container tomatoes

Her Kennebecs have grown 5 feet into the courgette plants, the spuds in tubs have grown almost 5 feet across the paving slabs, they're all still going strong and most tomato pots have had to be relocated to make room for them.

But in the last 31 years I've only had experience of growing spuds at a remote plot with no water supply, where after the rainwater barrel is emptied everything must be transported in water containers, not growing in gardens with water on tap, but I was careful not to overdo it in the early stages before tubers needed to swell up.

 

Some cuttings are now 8 feet tall, others only grew a couple of feet. A pot of 3 runts died back so I had a look. I want leave them to grow as big as possible to reduce the chances of tiddlers shrivelling over winter before replanting next spring.

 

Tipped out another pot, biggest was just under 3 ozs, wish I'd taken more cuttings because the better ones to follow will be big enough to plant for growing competition size giant spuds, saving a year on using them as micro tubers to produce seed spud size tubers the following year.

Another case of commercial seed stock being inferior to what you can produce yourself? They probably just produce micro tubers from stem cuttings to the basic size necessary to be capable of producing a crop of seed spuds the following year, but enthuastic amateurs may be able to get sizeable tubers a year earlier.



An amazing improvement on what they were produced from