As with all my veetables i grow my potatoes inlow raised beds. After growing Earlies and mains in seperate beds last year, i decided to reduce plnat number and spacing and grow them both in the same bed this year.
I planted earlies at on end and mains at the other, roughly 2 weeks apart. (earlies first). Both have grown well until recently although despite the weather the maincrop plants have remained visibly 'behind' the earlies, confirming their later planting date.
Recently the plants i know to be the earlies have started to flower, indicating that they are ready to crop. At the same time the maincrop plants have 'flopped' as they do when they start yo die back and are ready for croping. This cannot possibly be the case now i would not expect to start harvesting maincrop potatoes for at least another 6 to 8 weeks, depending on weather and how the earlies have cropped.
I had to do a check and I began to wonder if I had got the crop types muddled up and the 'flopped' plants were in fact the earlies. i checked my records and photos, and those plants were definetly mains (Maris Piper). I had also been very carefull to label the varieties when i bought the seed tubers, so the possiblity of a mix up at that stage is very slim (unless the nursery got it wrong!)
So the last possible explanation is either physiological problem (weather or soil) or some sort of pest/disease problem. This is where i am stumped and need advice since I cant think what it could be! Given the fact that the other potato plants (the earlies) are strong and healthy, I cant think that it could be anything soil bourne and its too early for blight. So what could be wrong?
Please help/advise.
noticed that my spuds had flopped too, but this is due to the wind and rain.
is it possible that the maincrop end of the bed is more exposed to the elements than the early end??
don't know about physiological or pest/disease causes I'm afraid!
It's not too early for blight, I'm afraid. It should be - but not this year! We've had a couple of isolated incidences of it.
But quite a few of my main-crop potatoes have haulm that is dying back. Is that what you mean by "flopped"? You would normally expect this to happen - but again, not this early. We had very warm temperatures shortly after they were planted, then plenty of rain to swell the tubers; and cooler weather reminiscent of autumn. It strikes me they have just carried out their normal life-cycle, but in a shorter time.
If you're worried, lift a root and see.
I've just checked Blightwatch, and there have been loads of Smith periods recently, so an outbreak is inevitable unless we get a serious period of dry weather.
Was in touch with DEFRA this afternoon (on another, unrelated, matter) and they confirmed that there is blight around due to the present damp weather.
sorry to hear about the blight.
I pulled up some surprise potatoes in my fruit bed last night and there was some wonderl potatoes there which i have pulled out and kept they look fine are these edable?
http://www.potato.org.uk/department/knowledge_transfer/fight_against_blight/blight_incidents.html?podlet_id=88&item_id=&sd=01&sm=06&sy=2007 (http://www.potato.org.uk/department/knowledge_transfer/fight_against_blight/blight_incidents.html?podlet_id=88&item_id=&sd=01&sm=06&sy=2007)
Two cases of blight on our plot already, one behind me and another two plots away so just a matter of time. Put all my outdoor tom plants in sacks last night too :( But look on the bright side - my maximus sprouts are doing well so might just have Christmas early this year, after all it's feeling like November already :o
There does not appear to be any suggestion of blight in the original posting, but more of the haulm `flopping` as if starting to die back.
All of my maincrop are flat on the ground - nothing to do with dying, but all to do with torrential rain beating them down, and they`re still growing, if sideways rather than upwards.
Tuber initiation in maincrop potatoes is governed by daylength, and has nothing to do with weather conditions except in so far as they would drastically reduce the number of daylight hours. For most maincrops - in my area at least - daylength would not have reduced to the point of causing tuber initiation until
about the third or fourth week in July, and the plants would not normally start dying back until at least three weeks or so later.
In the present case, I would adopt the principle (for the time being at least) of `wait and see`. We have had sufficient heavy rainfall recently to cause all sorts of temporary physiological problems, and what looks like dying back may be simply a form of weather induced chlorosis which could correct itself once (if ever) the rain stops.
Having said which, I often get the odd second early or maincrop plant dying back about now - this year I have (or rather had) 2 second earlies so affected. I always dig them up, there`s never anything underneath them, and usually they have been `got at`underground by either pest or disease.
I know the early signs of blight and i dont think its that. What i mean by flopped is just that the stems have fallen over rather than nice and upright (like the haulms on my earlies are). The have also made about a third less growth than the earlies before doing so. After lifting the first of my earlies today i ahd a rumage around in the soil beneath the mains, without disturbing the haulms and found no sign of any tubers.
So if they have 'bolted' ie rushed to maturity then they havn't produced much of a crop! :(
They haven`t rushed to maturity - the requirements of photoperiodic response don`t allow them to rush to maturity in June, as I thought I had made quite plain in my posting.
If the tops have not gone yellow then they`ve simply fallen over (like most other peoples`) under the weight of rain.
Garden Apprentice, you say that you have reduced the spacing this year. May I ask what the spacing is and why have you reduced it?
Check the stems of the flopped plants to see if they're going brown or black. Blackleg can cause the stems to flop over even before it is obvious and lots of wet weather can cause this disease.
Sorry kepouros i hadnt read your post properly ::). I guess it could be just the weather but as i have stated before the earlies have not been affected. Maincrop potatoes might be photoperoidic and as such dont 'bolt' like you said but they do appear to have stopped growing and yes there is some yellowing on what shoud be the lowest leaves. Contrast this behaviour to last year when they grew far more and stayed upright for far longer, and that was in a very dry year. i would have expected what has happened this year to result from drought and lack of water, not too much of it
I have to confess I have crammed the protatoe in a bit this year, planting the seed tubers around 6 inches apart rather than the recomended 12"plus. As i stated in my earlier post I have reduced the amount of ground used for spuds this year, but still wanted to grow as many potatoes. I did this on the understanding that in raised beds you can plant closer together and , Ok get a slightly reduced crop, but still get good results. In fact prior to last year when i decided to do things 'properly' I have tended to plant closer together than recommended and have usualy got a good crop.
Oh dear.
One of the most obvious results of crowding plants far too close together is that the stems become leggy and weak, and will fall over in heavy rain. Another result is that the lowest leaves often become yellow and sometimes die off prematurely.
The reason why planting/sowing distances can be reduced in raised beds is that there is a greater depth of soil for the roots to go down and less temptation for them to spread laterally. This is particularly applicable in the case of root vegatables such as carrots and parsnips, or those with a tap root, such as beetroot and turnips. Potato roots do not go down more than an inch or two however deep the soil - they fan out sideways from the bases of the shoots which spring from the eyes of the seed tuber (i.e. the top of the seed tuber), and however deep you make the raised bed the potato will still require roughly the same amount of lateral space. It is the size of the leaves and density of the haulm that dictates planting distances for potatoes, not the depth of the soil.
With such close planting the roots of the plants will intermingle, and there is an obvious danger that if you have one `dodgy` seed any viral or bacterial infection may spread to surrounding plants.
SUBJECT: Potatoes have nasty scabs:
(1) what is the problem/disease?
(2) are they edible?
Hi
[BTW, I thought I'd add this to an existing thread that covers a similar problem, rather than start anew. In case anyone reading that thread has any good advice! So here goes . . . :]
I have just harvested 2 batches of my potatoes (grown from seed potatoes). I have 4 different varieties in 4 different pots (i.e. one variety was grown per pot) These are:
Charlotte; Desiree; Maris Piper; Vales Emerald.
Sadly we don't know which of the 4 we have harvested! I think 1 of them must be - from its reddish colour - the Desiree; but cannot be sure(!)
The problem is that neither batch looks very healthy.
Both types have the same problem - plus the same problem is present on ALL the potatoes in the batch: they have nasty brown scabs. Plus some of the potatoes look like the skins have been stretched; in fact I'm worried they might?! have been burrowed into.
We are new to growing potatoes, but tried some last year for the first time and did NOT have this problem in 2012.
I wonder if it is several problems, perhaps one problem leading to the other?? Any ideas??
P.S. Later, I will include at this forum either some photos of several of the potatoes (if I can find a way of uploading attachments!) OR a weblink to a URL to an online photo-storage website.
I have 2 main queries:
1. Can anyone tell me if the potatoes are edible if the skins are removed/peeled (then cooked, of course! LOL!)? We HAD hoped to boil & eat these with an evening meal, but sadly now will have to wait for a reply here!!
2. Can anyone help me identify the problem by name so that we can:
(i) research any disease online
(ii) hopefully avoid the same problem when we try growing tatties from a new batch of seed potatoes, next year.
BTW, we found a slug in one pot & at least 3 snails on the edges of both pots. Would this have caused/contributed to the problem?
All help appreciated!
Thanks
TuttiFrutti
Two diseases cause scab on potato skins:-
1. Common scab - more prevalent in hot dry conditions and on sandy soil. Maris Piper is one of the most affected varieties.
2. Powdery scab - this disease is worst in cold wet summers, it is spread by infected tubers which can infect the soil and can affect a potato crop some years later when variety and soil conditions are suitable.
With both these skin conditions, the underlying tuber is unaffected and is perfectly good to eat. It is probably best not to compost the peelings , although Common scab is not seed transmitted, Powdery scab can be so similar that only an expert can tell them appart.
On some Potato varieties, Powdery scab can cause growth knobbles and cankers on the tuber.
Yes they are edible. The scab is only skin deep. I was taught it was lime in the soil that causes scab. The stretching of the skin is with lack of water then sudden watering.
Quote from: TuttiFrutti on August 29, 2013, 14:08:41P.S. Later, I will include at this forum either some photos of several of the potatoes (if I can find a way of uploading attachments!) OR a weblink to a URL to an online photo-storage website.
Thanks! We didn't want to poison ourselves! ,-)
If it helps, some photos of both batches of scabby potatoes are viewable at URL: http://s1235.photobucket.com/user/In-The-Frame/library/Potato%20scabs%20-%20crop%20of%2021Aug2013
Lime in the soil can very frequently result in scab on the potatoes, but scab can also result from the soil becoming very dry - as has very probably happened in your plot this summer. Unfortunately, in Desiree, you picked probably the most likely candidate of all for scab. I would suggest that when you lift the crop you take great care to make sure that the skins are properly dry - particularly the scabby bits. If the scabs are properly dry there is usually no problem in storage, but ifthe tubers are stored with the scabs still damp there is a danger that they will `weep`, leading to rotting in storage
We have very limey soil so we are very prone to scab. Made even worse by tap watering which is very high in lime. I try and produce leaf mould, so they can be grown in that. Putting comfrey round the potatoes helps as well. If you cannot produce enough leaf mould them straw is a good substitute.
It is odd to think of Desiree as particularly prone to scab because when I first started growing it about 25 years ago Desiree was particularly clear of it. I have become convinced that Desiree has more than one genetic form. The older variety tasted better as well and had particularly long oval potatoes.