Growbags and blight

[compostmonkey]

Hi, my toms that I grew in growbags in my tunnel this year all eventually got the dreaded blight.Thankfully I had a great crop before the worst hit.

Is it ok to use the spent compost out of these bags to add to my outside raised beds?

Many thanks for any advise :)

[compostmonkey]

[saddad]

Yes the spores won't survive on the open ground. They do survive in plant material like outgrade piles on farms but not in the amounts of material you may have...  :)

[Robert_Brenchley]

It survives in living tissue, so the two dangers are the outgrade piles Saddad mentions, plus volunteers. It's endemic on many or most allotment sites because people don't get the left-behind spuds which come up the following year. If everyone was ruthless about digging them out as they emerge, there would be far less of a problem.

The other possible danger is seed potatoes. In the States, up to 1% can be infected; I don't know what the position in the UK is. Hopefully standards are a bit higher over here!

[Vinlander]

Yes the spores won't survive on the open ground. They do survive in plant material like outgrade piles on farms but not in the amounts of material you may have...  :)

To be more precise common late blight* can't survive except in LIVING plant material - so in this country infected tomato plants are entirely safe - unless you grow them in stove-house conditions where they can overwinter - which is really difficult in these latitudes.

Potato tubers are a PERFECT host for blight - though most will usually succumb before they pass it on - some will survive to put up infected shoots.

*There is a risk of newer strains emerging which might overwinter as breeding spores - but assuming local hygiene will protect you from this is like trusting aspirin against the Black Death.

[PurpleHeather]

I agree and re-use compost all the time it has never been a problem.

Personally I think that there is a lot of scaremongering about infestations promoted by producers of products who want us to keep buying new things, from them of course.

Farmers who depend on their crops for a living do have to be sepcially careful and often 'spent' or used compost from them can be obtained at little or no cost if one is trying to increase their soil volume. Harder to obtain these days as the gardening  hobby is becoming more and more popular.