[shokkyy]

Since I've been hit quite badly by blackleg in my spuds this year, I'm trying to find a way to move them to a new bed next year. I can't do proper rotation on them because my other veg beds are all raised beds with not enough soil depth for spuds. I've got one spot next to the house that used to be an old boiler room which has been knocked down, and right now it's grown over with grass, but it would make a good sized bed for spuds.

Would it be ok to just dig out the grass, smother the whole lot with rotted horse manure, and plant spuds in that next spring? Is there anything else I should be doing to prepare the patch or is that enough? One downside of this bed is it is in the shade of the house for quite a good part of the day. It's on the east side of the house. Will spuds mind that? And will one year of rest be enough to get rid of the blackleg in the old spud bed, given that I'm diligent about removing any escapee spuds that pop up next year?

[mikem]

You could have a problem with wireworm if you grow potatoes for a couple of years.  It may be better to cultivate it and use it for other vegetables for say 2 years.

[shokkyy]

You could have a problem with wireworm if you grow potatoes for a couple of years.  It may be better to cultivate it and use it for other vegetables for say 2 years.

Do you mean wireworm in the new bed? If so, why's that?

[JayG]

Grass roots are the preferred host for wireworm (the larvae of a type of click-beetle), so previously grassed-over ground is likely to contain them.

I think Mikem probably meant that you could have problems for a couple of years if you grow potatoes in such ground rather than potatoes being the cause of the problem.

They do decline in numbers once deprived of their preferred source of food; you could try "baiting" the ground with cut-up pieces of potato on sticks to try and "fish" some out or just cross your fingers and hope for the best!

[shokkyy]

Grass roots are the preferred host for wireworm (the larvae of a type of click-beetle), so previously grassed-over ground is likely to contain them.

I think Mikem probably meant that you could have problems for a couple of years if you grow potatoes in such ground rather than potatoes being the cause of the problem.

They do decline in numbers once deprived of their preferred source of food; you could try "baiting" the ground with cut-up pieces of potato on sticks to try and "fish" some out or just cross your fingers and hope for the best!

Thanks for that, now I understand. So basically I'm caught between a rock and a hard place - wireworm or blackleg

[JayG]

Grass roots are the preferred host for wireworm (the larvae of a type of click-beetle), so previously grassed-over ground is likely to contain them.

I think Mikem probably meant that you could have problems for a couple of years if you grow potatoes in such ground rather than potatoes being the cause of the problem.

They do decline in numbers once deprived of their preferred source of food; you could try "baiting" the ground with cut-up pieces of potato on sticks to try and "fish" some out or just cross your fingers and hope for the best!

Thanks for that, now I understand. So basically I'm caught between a rock and a hard place - wireworm or blackleg

That's too negative shokkyy! Blackleg can carry over to the next crop in the short term so rotation is important but it is far from being the worst or most persistent potato disease.

As for your proposed plot; dig it ASAP, let the birds find any wireworms which might be there and give it a go next year; there might actually be no wireworms there, nothing is exact about the science of gardening! 

[shokkyy]

That's too negative shokkyy! Blackleg can carry over to the next crop in the short term so rotation is important but it is far from being the worst or most persistent potato disease.

As for your proposed plot; dig it ASAP, let the birds find any wireworms which might be there and give it a go next year; there might actually be no wireworms there, nothing is exact about the science of gardening! 

Blackleg has pretty much devastated my crop this year, took out a row of Desiree and one of Sante. I think the problem is there were spuds left in the bed from last year, and that was where it came from. So it wasn't just one plant, it was spread through the plot. It only showed itself with black mushy stems in a couple of plants, which I lifted, but the rest of them grew quite big then just suddenly lay down, with the whole row going as one. The row of Sarpo Axona that sat between the two has survived, but not as strong as it should have been. I've salvaged small spuds from the Desiree and Sante, with no sign of rotting in the spuds themselves. I'm crossing my fingers the Axona have managed to grow some decent sized spuds. But given that it was so widespread, I think I need to try to give that bed a rest. Is there anything I can grow in there in the meantime that would help/hinder the bed in getting itself healthy?

So I guess I'll give the new bed a go. It's been about 3 years since the boiler room was knocked down, so the grass hasn't been there that long. And I do have a very healthy population of birds in my garden, which do a fab job of controlling a lot of the pests, so fingers crossed.

[paintedlady]

sorry to hear of the problems you had, but this does show a good reason for crop rotation - growing a crop in the same bed year in year out allows a build up of pests and diseases that affect future crops 

One downside of this bed is it is in the shade of the house for quite a good part of the day.

Potatoes ideally should get as much sunlight as possible - sunlight converts CO2 and water to sugars and starches which are stored in the tubers.  I'm a bit concerned that you may be disappointed with the crop.  My other concern is that the shade may also encourage slugs which seem to do more damage than wireworm, not to mention if we had a damp season ...

With regards to the raised beds, may I ask why you think they won't be deep enough?  Do they have a concrete/stoney/solid base or you haven't been able to dig down?  If the latter, you might be able to get away with growing potatoes - why not just go for a 1st early rather than maincrop next year, or try growing some in containers rather than none at all?

[madcat]

To give a positive slant on the bed - our main allotment bed was cut out of pasture land 3 seasons ago.  Yes, in year 1 there was wireworm and slugs, lots and lots of them - but they did more damage to the softer crops (like eating an entire row of brassicca seedings in a night ) than the potatoes.  The potatoes thrived and all the digging and hoeing and earthing up meant they were lovely clear beds for the following year.  Maybe there was more damage than a clear bed but not so much that some careful peeling couldn't cope with.
Last year we brought another bit of very shady pasture into potato production, nearer to the stream so more slugs and with all the wet we had they multiplied  ....  But the crop was huge  - the problem was getting them all dry to store.

My tip would be to grow your potatoes (perhaps going light on first earlies which appreciate the warm) and actively encourage your small birds to forage the area before and during growing time.  We had more problems with slug and wireworm where we had to net against the *bleep* pigeons, than where the birds could get in and feed.

[PennyS]

If it helps, we got our allotment last August, it was all grass and weeds, having been grazing land for a long time.

I hand dug it all, removed all the couch etc and went straight into planting.  

About a sixth of my plot is potatoes.  I did see quite a few wireworms as I dug (killed them as I went!).  I did plant quite a lot of potatoes and the wireworm damage hasn't (so far) been too bad.  (Thinking back, I only managed to clear the potato patch just as I was ready to plant, so I didn't even get to manure it).

Most of the First Earlies escaped completely.  Some of the Seconds have been a bit affected, some not.   I've yet to harvest any maincrops so can't tell you what's happened there yet (although may have a rootle today).  

With the potatoes, I planted several varieties so that if one proved more susceptible than others, there should be enough of the others, if you see what I mean.

Hope this helps!
Penny

[shokkyy]

Thanks for all the advice, that's very helpful. I do grow my earlies in containers, and just use the bed for maincrop. And yes, the raised beds are just 6" of imported topsoil sitting on a concrete base. I get fab crops of tomatoes, courgettes, onions, strawberries, little carrots, peas and beans on it, but that's not enough soil depth for spuds.

Whenever I pick up a spade in the garden, I instantly have a couple of robins sitting behind me, waiting to swoop on whatever I turn up. And not only birds, but we also have a good population of hedgehogs, voles, shrews, toads, foxes, all of which are very helpful at swooping up that kind of pest. The only thing I ever net is the strawberries. I never seem to have problems with slugs in my garden and I suspect that's why. I do think if you look after the wildlife they tend to pay you back