[arh]

So, if main crop potatoes take approx 15 weeks to maturity, and I put mine in bags on the 13th of March, which was 15 weeks ago, then they should be ready for lifting, yes??.
But they are still flowering, (and producing seeds). Am I correct in thinking that they should be left until the tops die down?, and that they can be left even longer than this, (as the slugs etc. cannot get at them, hopefully)?. The bigger, the better is what I'm hoping for.

[m1ckz]

me thonks the slugs  CAN get them

[arh]

To be honest with you M1ckz, slugs aren't on my worry list, as I haven't found 1 yet. Its new "earth", as the plot was under 6" of concrete last August, and, on a tarmac "island" so to speak, . I know that they will turn up eventually, but not this year, hopefully.

[al78]

Some maincrops take a bit longer than that to mature. I would guess that spring weather conditions will affect maturity rate. Here in Sussex we had a hard frost at the end of April which knocked some of my potatoes back 2-3 weeks. The dry spring may have some effect as well, I'm not sure. I normally leave potatoes until after flowering and the foliage starts to die down. With maincrops I think it is advised to leave them in the ground for a couple of weeks before lifting. If you have a blight risk (Smith period) in your area you may want to cut the foliage down before it dies back naturally. If the slugs find the tubers, they will feast on them regardless of when you lift, if you have a high slug population applying nematodes a few weeks before expected maturity date should hopefully knock that risk down (although maybe a bit late for you now).

[arh]

That's the info I wanted Al78, thank you, arh.

[mumofstig]

15 weeks for Desiree is a bit optimistic for a main-crop harvest IMO.

From John's potato advice page http://www.allotment-garden.org/vegetable/potatoes/potatoes-growing/

First Early – these are the fast developers who produce new potatoes. Depending on variety they will be ready to harvest between 10 and 12 weeks after planting.
•Second Early – slightly slower these are ready to harvest between 13 and 15 weeks after planting.
•Maincrops – these take anything from 20 weeks for the early maincrop varieties to 26 weeks for late maincrops.

I wouldn't be looking at them 'til after 20 weeks, or else wait til they die back naturally.

[arh]

Thank you for that Mum, I'll wait till they die back. arh.

[compostqueen]

A Desiree is a rock hard spud!  Slugs might have a go but if there's something softer available they'll go for that 😃
E.g. Your neighbour's Kerr's Pink 😎
 I find you can leave your Desirees in. I pulled some in November and they were fine. They were planted too near the hedge, which grew over them so,I,forgot about them

[arh]

Thank you for that info Compostqueen, I'll try to tip and use them by the bag, as it were. Next year the bags will be further apart and will have a foliage support system put in at the outset, I'm having a hard job finding the bags, not to mention the gooseberry bushes which are/were next to them, luckily I'm not using the bushes as they only went in last November, but it'll be interesting to see what state they are in. More info and experience gained. Thank you again, arh.

[New shoot]

You could always tip out a couple of bags if they are swamping the gooseberries and leave the rest to grow on.  You should have something, but they won't be at full main crop size yet.  The skins will be softer as well, so they would be for eating up now, rather than storing.

I quite often either plant a variety that spans a gap e.g. Kestrel which can be a second early or an early main, or plant more of a main than I need or can store, then I can raid them a bit earlier.  As you might have guessed by now, I am a repeat offender for furtling 

 
 

[arh]

Thank you for that Hun, I think the gooseberries can take care of themselves, they've had a reasonable amount of water on them, (aimed at the potatoes,  ). It'll probably do the roots good. Time will tell, (when the spuds get pulled,  ). arh.

[Aidy]

Reds generally have better slug resistance than whites, at least they do up this kneck o woods!

Wait for the top growth to die back then munch away