My Urban Oasis: August 2009

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.

This is the third very wet July in a row now, and possibly forming something of a trend based on the jetstream flowing across the country in high summer as opposed to well north of the British Isles. It's a long, long time, July 2006 or maybe the unseasonably warm April 2007, since I was worried about water shortages and my waterbutts have remained full throughout the summer thus far. Even if things dry up now I think the ground is so well charged with water that there will be no danger of drought affecting my plants. Although the rain is welcome, I would appreciate some settled weather now to help ripen the outdoor tomatoes and other fruits that rely on sunshine and warmth to attain their full depth of flavour

After yet more copius rainfall this week, with over an inch on Wednesday and a similar amount during Saturday's deluge, the sun finally shone on Sunday for a trip to the plot. As my sister was visiting for the weekend it was a chance to show off the allotment in its prime and send her back to Harrogate with a bag of fresh veg. I was also able to demonstrate the delights of a freshly picked apricot - the 4th and final ripe fruit I'd been saving in anticipation of a family visit. It was/ they were all delicious!

Everything appears to be flourishing thanks to all the rain, with the beds looking full and lush and no signs (yet, touch wood) of any blight, mildew or general ill health amongst the plants. We managed to pick some huge beetroot, several large courgettes, a punnet of raspberries and blackberries and about half a bag full of beans. There are also some decent squashes forming now, with the first of the butternuts also setting fruit.

Here's a few pictures to show how things have progressed since mid July.

Looking across the plot to the polytunnel - rows of celeriac, beetroot, scorzonera, carrots, parsnips and potatoes...