Topic: Compost Blight?

[7oaks plot]

Hi everyone I am new here even though I've had an allotment plot for a year now I still need to know so much so what better way than to ask fellow allotmenteers.

My problem is this, last year owing to lack of space on my plot i grew my Tomatoes in containers and because my potatoes got blight so did the tomatoes so what i need to know is, is the compost in the tomato containers now contaminated as i had planned to incorporate it into my raised beds, i wont be putting it where the potatoes are going to be planted obviously but would it be OK to put it in my other beds with all the other types of vegetable.

I hope that all makes sense and wonder if anybody has the answer.

Thanks and bye for now from a very very wet Sevenoaks, Kent.

[kt.]

If stuff has one disease you can see, you can bet it has others that you can't see. I would suggest it is best to cut your losses and start over.

Personally, I don't use anything that has been diseased. If it is diseased then it gets burnt or skipped, but is definitely not used in my plot.

[Uncle Joshua]

If stuff has one disease you can see, you can bet it has others that you can't see. I would suggest it is best to cut your losses and start over.

Personally, I don't use anything that has been diseased. If it is diseased then it gets burnt or skipped, but is definitely not used in my plot.

I'm the same, burn it or bin it.

[redimp]

If stuff has one disease you can see, you can bet it has others that you can't see. I would suggest it is best to cut your losses and start over.

Personally, I don't use anything that has been diseased. If it is diseased then it gets burnt or skipped, but is definitely not used in my plot.

I disagree totally.  It will be fine if it is going where nothing from the solanum family is going.  All my potatoes and tomatoes got blighted last year and I certainly ain't digging up and disposing of 60m² of soil, and my broad beans have been all right so far.

Do bear in mind though that it will be exhausted so is more of a soil conditioner rather than additional fertility.

[Eristic]

OK. Lets warm up the room a bit. Last year I remember some serious debate at the height of the potato blight where the more scientific members of the forum stated that blight spores only survive days or a few weeks when not on living solenoids. While I am not convinced about this, it would follow that if all the tomato plant, leaves, roots and fruit were cleared away, the compost should be safe to use this year even for tomatoes. To be safe, I recommend not using the compost for susceptible crops this season but it should not be wasted.

[kt.]

I disagree totally.  It will be fine if it is going where nothing from the solanum family is going.  All my potatoes and tomatoes got blighted last year and I certainly ain't digging up and disposing of 60m² of soil, and my broad beans have been all right so far.

Do bear in mind though that it will be exhausted so is more of a soil conditioner rather than additional fertility.

Possible misunderstanding here. I mean not to use the home made compost, made from last year. I wouldn't dream of excavating a plot ;D ;D

[Robert_Brenchley]

Blight can only survive long in living tissue, so there's nothing to worry about. If your compost is contaminated, then most of my plot must be.

[morton]

I am no expert with blight although, like everybody else, I have suffered from it for the last few years with the weather being as it is. I may be wrong but my thoughts are that most people would have cut the tops off of their potatoes at the first sign of blight and as such it would not have gone through the plants into the tubers and in to the soil.
Similarly with tomatoes in pots you would not have let them die right back from blight. You would take the leaves off at the first signs to try to prevent it spreading through the plant. If it took hold you would cut them down so the compost should be ok to spread around the plot.

[redimp]

I disagree totally.  It will be fine if it is going where nothing from the solanum family is going.  All my potatoes and tomatoes got blighted last year and I certainly ain't digging up and disposing of 60m² of soil, and my broad beans have been all right so far.

Do bear in mind though that it will be exhausted so is more of a soil conditioner rather than additional fertility.

Possible misunderstanding here. I mean not to use the home made compost, made from last year. I wouldn't dream of excavating a plot ;D ;D

No misunderstanding - I was trying to show that if you wouldn't chuck away that much of blighted soil because blight is not a risk if you rotate, why waste compost when it too can be rotated.

[manicscousers]

Hiya, 7oaks, welcome to the mad house, we re- use all our compost and have done for many tears, as everyone has said, not on susceptible plants..I hate to see anything skipped, most of all compost and plant materal  :)

[Magnolia]

Can I jump in with a related question?

I will be planting in a lot of containers this year (no allotment yet and only a small veg patch).  I have no idea what to do with all the compost after it's been used.

Would you empty the lot and make a pile to mix in with fresh compost for next year?

[manicscousers]

hiya, magnolia, we empty the compost from our containers around other plants as a mulch :)

[calendula]

it is always good to have as many compost bins as space will allow and then you can make sure one at least is a 'long termer' and in time I'm pretty sure no disease will thrive - it's never bothered me in all the years I've been growing fruit and veg - one way or another nature will do 'its' thing  ;)

[Toadspawn]

I would never dream of discarding compost from tubs, grow bags, pots etc even when the plant has shown signs of foliar disease. It always gets incorporated into the rest of the garden as a mulch. I have even used the compost (with added nutrients) from growbags used for peppers/chillies in the GH as a basis for potting on larger plants. So far no problems.

Blight does not remain in the compost, only on living material so it would be perfectly safe to use the material from growbags in which tomatoes had become infected with blight for tomatoes or even potatoes in the next year provided ALL living material has been removed.

[Magnolia]

But is it ok to use some of the old compost that I have in pots from my earlies, mixed with new, to use in pots again.  Mixing a bit of fresh with the old and planting on in the same container?  Other wise I can see it being quite expensive buying new compost for each container.

For example - using a mixture of old compost & new from 1st early spuds with main crop.

x

[Toadspawn]

No reason not too but you will have to improve the fertlity level because the old compost will be significantly depleted of nutrients.
Also be careful in case the potatoes were infected with any of the soil borne pathogens eg Fusarium spp. or potato cyst nematode.

However I always use new compost for growing potatoes in containers. The extra cost is justified by the better crop.

You do not need to fill the container to plant potatoes. Put about 3" compost in the bottom of the container and put a tuber on the top. Cover the tuber with a handful or two of compost, water carefully and stand back and wait. As the shoots grow add more compost to the pot until the pot is full like 'earthing up' . Keep the pot well watered and add fertiliser as you add extra compost.
 
Can you not give your used compost away if you have no where to spread it?

[flowerofshona2007]

I use my 'spent' compost on my flower beds  :) that way it improves the soil and is re used but no chance of any nastys in your compost or plot  :D

[Magnolia]

Cheers.  Thats great stuff.  Yes I can always give the used compost away through freecycle or my mates with allotments...  hadn't thought of that - duh!  Many thanks. x

[cornykev]

Hi 7oaks and welcome to the asylum, blight totally wiped out my Tommie's but never got to my spuds, luckily I had Tommie's growing at home, so this year all my Tommie's will be grown at home. The blighted plants were bagged and stored in a corner, burnt later and ashes spread on the soil, the compost you mentioned can also be spread on the soil, but I wouldn't use the compost in containers the following year as the nutrients would be spent, well that's my three pennith worth.  ;D ;D ;D

[alienwithaview]

I don't re-use "spent" compost - from tomato pots or similar container crops - immediately, but put it in the compost bins, where it bulks up the kitchen waste which I first treat with bokashi. This way I'm quite confident that any diseases which might be in the old compost are broken down sufficiently and that the nutrient-poor soil is mixed in nicely with the "fresh" stuff.
Admittedly we only moved here last summer, and although we have three compost bins on the go they are all at the same youthful stage now. Long-term we hope to rotate them for a continued supply of compost all year round.
With regards to blight at the allotment, which killed off our tomatoes last year and caused much panic and disillusion amongst all our neighbours, we are planning to put in spuds this spring, although not in the beds we had the tomatoes in. I understand that blight needs rain and as it is airborne it affects and acts through the leaves, not the soil, so it's just a question of keeping Wiltshire sunny! Anyone with some farming wisdom for a long-range weather forecast?