The early Pentland Javelin spuds were beautiful, great crop and I was thoroughly impressed!
Have started digging up some main crop of Desiree and King Edward, all of them have got terrible scab... one is not happy!
I have read that scab is caused by bacteria in most soil and mostly affects crops when its hot and dry, I did not water the spuds much, my bad!
Am I right in thinking they are still ok to eat? Do they still store well?
I am thinking of digging them out, storing some as usual but peeling most and preparing them into things eg roast spuds, hash browns etc and then freezing them
any ideas?
Your potatoes should be fine to eat.The scab is just on the surface and not in the flesh.It will be gone once you have peeled them.
beautiful... ta for that
is it a common problem for people?
I've had a bit of scab here and there but not as you describe, as Fork says once peeled their fine but I would leave them in the ground and dig them as you need them, I wouldn't think they would store well. :-\ ;D ;D ;D
Some varieties of potato are particularly prone to scab, and Desiree is one of these. However it can arise with most varieties - generally as a result of the presence of lime in the soil, and the moral is always to lime after the potatoes so that, with normal 4 year rotation, the lime will have disappeared by the time for the next potato crop.
It is important with badly scabbed potatoes to make sure that the skins (especially the scabs) are thoroughly dried off before they are put in to store.
It is a common problem in dry conditions.
I was in Tesco's yesterday and coincidentally took a look at the spuds there - all the bags of desiree we're suffering from a bit of scab, unusual for shop bought potatoes.
After accidentally coming across a UK farming forum a few weeks ago, it doesn't surprise me. They were all lamenting the lack of rain and wondering whether to use 'mains' on their tatties.
it sounds like have nothing to fear....
its the 1st year on the allotment so I may have grown the spuds in a bed used not so long ago for spuds, or full of lime... who knows, no one knew what the previous tenant had grown where... and I did ask, so it has been a bit of pot luck and guess work this year... I think i will avoid desiree next year now :)
Today I found some of mine have scab as well. 1st time I've ever seen it / had it. It's on some spuds that were given to me - Nicola or Nadine (I can't remember!). And I'd presumed I wouldn't be able to store them so this is a useful thread.
Thinking about it, they are the last line of spuds before an area I'm growing various brasicas on and where I'd added some Mushroom compost - I'm presuming that there may have been a bit of the shroom compost that has affected this line of spuds?
Live and learn eh..... !
1066
Mushroom compost usually has a high pH and is best avoided for potatoes. Chicken pellets also are better avoided in soils where scab has been a problem.
ahhh i put chicken pellets on my spuds to, on advice of others... thats clearly not going to have helped... I know for next year now
;)
La Ratte potatoes were fine - but Vivaldi are quite badly affected - taste fine though. Can anyone tell me how I got scab when I grew my potatoes in bags of compost - and we have had the coldest, wettest July and beginning of August for 10 years. Could the scab have infected during the dry and warm May and June?
Meg
Quote from: Kepouros on August 08, 2010, 15:45:37
Mushroom compost usually has a high pH and is best avoided for potatoes. Chicken pellets also are better avoided in soils where scab has been a problem.
Thanks Kepouros, I'm a bit cross with myself about it, and what annoys me is that the mushroom compost was in the bed next to these spuds, and has managed to leach - so where was my brain that day?!. Let alone the dreadful yields I'm getting. At this rate there will be hardly any worth storing. Just hope the brassicas do well!!
Oh well next year .....
Just emptied a second barrel of vivaldi and not a speck of scab in sight - dont understand this ...
Meg
we need the experts on this one Meg! Hope someone comes along shortly!
bump... any experts in the house?
I dug some more King Edwards yesterday and they had less scab on, then another had none at all.... and its next door to one with scab
I am all confused
Quote from: rog_pete on August 10, 2010, 19:17:12
bump... any experts in the house? I am all confused
Me too rog_pete - I emptied my last barrel of Vivaldi and they are lovely, not a sign of scab on any of them - and it was a big barrel - almost 7 pounds.
Need to hunt for more scab resistant ones next year - anyone got any recommendations?
Meg
I'm no expert, but here goes, there are two types of scab, common and powdery.
Common scab occurs under dry conditions on a light soil.
The powdery is less frequent and occurs on heavy soil in wet conditions.
If you don't know what was grown there before then make sure you rotate, all I can think is that the person before you limed for brassica's and you've hit a few pockets that were over limed, well thats my three pennith, the real experts will be along soon, Iain its time to show us your stuff. ;D ;D ;D
Wilja. ;D ;D ;D
Unfortunately it would be impossible to give definite opinions as what caused the wide variation in incidence of scab in the above postings without actually seeing the soil and doing a pH test.
However, I will hazard the following suggestions:-
As to meg_gordon`s postings I am a little confused. In the first she says the potatoes were grown in bags of compost, but in the second she refers to a second barrel. So was each batch grown in a separate bag of compost straight from the shop, and was the compost in the barrel identical and from the same source? And was the moisture in the compost in each bag/barrel maintained at exactly the same level? The reason I ask is that every bag of soilless compost, unless it is designed especially for calcifuges, contains some amount of alkali in the form of calcium carbonate or magnesium limestone. The amounts of this will vary according to the nature of the materials making up the compost and the whim of the manufacturer. If the compost in the barrels was different from that in the bag then that is most probably the answer. But even if the compost was the same the effect of the alkalinity on the plants can also vary according to the moisture level of the compost.
As to rog_pete`s query, then as cornykev suggests, the most likely answer is a combination of dry soil and the wrong rotation. The most usual cause of this is when the beds are changed from crosswise to lengthwise, or vice versa, resulting in a chequerboard of soil variations from previous crops, with limey bits, well composted bits, bits with little or no humus, etc., and a lengthy dry spell in such circumstances can produce a strange variety of results.
Quote from: Kepouros on August 10, 2010, 23:35:04
The reason I ask is that every bag of soilless compost, unless it is designed especially for calcifuges, contains some amount of alkali in the form of calcium carbonate or magnesium limestone. The amounts of this will vary according to the nature of the materials making up the compost and the whim of the manufacturer.
Wow, thanks for that Kepouros - it's something I've wondered about and asked about before because there are always warnings on shop compost about not using on acid loving plants which makes me believe they might be a touch too alkaline for potatoes but who knows how alkaline exactly, they don't say.
How do you know this stuff, I'm curious?
I do think last year I got very scabby results where I resorted to cheap DIY store compost so I didn't use it this year and got much better results.
Quote from: Kepouros on August 10, 2010, 23:35:04
As to meg_gordon`s postings I am a little confused. In the first she says the potatoes were grown in bags of compost, but in the second she refers to a second barrel.
Sorry about the confusion Kepouros - I have 8 large plastic barrels - about a metre in diameter each and I used bags of compost all from the same place, so I meant they were grown in compost from bags as opposed to compost from my compost bin.
Quote from: Kepouros on August 10, 2010, 23:35:04But even if the compost was the same the effect of the alkalinity on the plants can also vary according to the moisture level of the compost.
I watered daily (unless it was raining) so each got roughly the same amount of moisture and they were all together - in the same area - but thanks for the suggestions.
Meg
thanks for the advice Kepouros
I think it is going to be a combination as you suggested, being new to allotmenting and taking on a new plot where I had no knowledge of what had gone where before has proved to be very hit and miss! I know for next year what is going where and have my rotation all sorted out, so next year will be cracking!
It has been very dry and I did not water enough, so that has def brought the scab out more!
I shall be Ph testing my soil... what is a good Ph value to be at? I think from memory most of my soil is around 6
rog_pete, pH 6 is definitely on the acid side - 6.5 would be better for vegetables. However, are you sure that it is naturally 6, or is this the reading just after you`ve manured? Manure will lower the pH quite sharply at first, but this is only temporary. In practice whatever (within reason) you put on your soil to alter the pH, the soil will slowly return to its normal natural pH level as whatever it was you added is slowly oxidised or neutralised.
I had put nothing on the soil, this was what the ph test said back i december when I had taken the plot on... so I do not know if it had had any treatment or not before I did the test
maybe I need to look into this more and get the Ph better... another test at the weekend maybe in order
I think the overall quality of soil is good, its a good texture and structure and clearly grows well, just need to make my technique and knowledge better :)
If you`re relying on a pH meter attached to a probe don`t just stick the probe into the ground and read the meter. Take proper samples from several inches down and mix each one into a paste with water and then test them with the probe; that way you will get a much truer reading.