Blight strikes again

It appears my optimism of earlier posts was premature. Visits to the plot over recent days have shown again the damage that blight can do to both potato and tomato crops in a relatively short period of time.

I first noticed a few blight spots on my maincrop King Edward potatoes last week, so started removing infected leaves in an attempt to delay its effects. I suppose it helped to keep the plants growing for as long as possible but today I decided to cut my losses by removing all the top growth of the plants after the majority of the foliage became infected. I'll leave the tubers in the ground for a fortnight or so for the skins to harden and for the blight spores to disappear and then lift the crop about a month sooner than I'd hoped. Only time will tell whether the potatoes have had enough time to bulk up and provide a worthwhile crop. As for the haulms I've removed, they'll be burned as soon as I get the chance.

Unfortunately my tomato crops in the ploytunnel and outside have also been affected, with far swifter and more devastating results. Tomato blight often appears after the potatoes have been affected but decimates the plants in only a few days rather than over a longer time period. I'm particularly annoyed about the polytunnel crop as one of the main reasons for buying it was to protect my tomatoes after the failure of outdoor plants in recent years, but all to no avail. Again the plants have been stripped of diseased foliage and I've salvaged what I could of the green tomatoes. Together with the tomatillos and a few courgettes I'll make a good batch of chutney, but it's not quite the same as enjoying fresh, ripe tomatoes for the next couple of months.

Blight is now an annual occurence on our site, usually arriving around the beginning of August. Of course it is triggered by the wet and humid conditions that have prevailed in recent summers, but I also feel that, collectively, plot holders don't do enough to mitigate the effects by taking early and decisive action when it does appear. A few on our site spray their crops with Dithane but the majority garden organically and do not spray, me included. Unfortunately the term 'organic' appears to be synonymous with 'do nothing', which couldn't be further from what is actually required to obtain good crops of organic vegetables and fruit.

Soils need to be nurtured and improved annually and plants must be grown healthily to combat the various pests and diseases that would otherwise be tackled with chemical sprays. It is also vital that action be taken to address fungal infections, such as blight, that can devastate not only your own but everyone else's crops in so little time. If action is taken early with blight, such as the removal and destruction of all infected leaves on a regular basis, the plants can be maintained for long enough to at least get a half decent harvest. But if one plot is left untouched, the blight is spread around the site more quickly than might otherwise be the case and any efforts you take end up being futile.

I'm sure there is a lot of confusion about what blight actually is, its effects and how to counter them, so I'll be putting together as comprehensive a guide as possible for next year and circulate it with the quarterly newletter I produce for the site. Hopefully plot holders will then know what to look for and, more importantly, the action they can take, whether chemical or organic, to address the problem.