Monday 13 June 2011

Sunshine and showers

sun and showers

The showery weather continues but in the last day the temperatures have ramped up again significantly. This is important because until now the chilly nights have provided a measure of protection against the proliferation of blight spores. As soon as the humidity is matched by warmth for a couple of days then an event known as a Smith period occurs. The Smith period is defined precisely as at least two consecutive days where the minimum temperature is 10ÂșC or above and on each day at least 11 hours when the relative humidity is greater than 90%. This is just what the blight needs to sporulate and spread. Add to this the fact that frequent showers are keeping the plant leaves wet and the possibility of blight on the potatoes becomes almost inevitable.

Tomorrow, in a brief predicted moment of dry I'm going to try spraying with Bordeaux mixture. If the blight can be held away for another month we'll probably have a fairly good crop because of the very early start.

shot spinach bloomsdale

While I was in Italy the spinach bolted. Not an unexpected event given the circumstances and on the few occasions it's happened before I've just ripped the plants out pronto to make room for something else, but this time I thought I'd let nature take its course and see if I could save seed.

This was the moment that I discovered I knew less than nothing about Spinacia oleracae. It's quite unusual as a annual vegetable in that it is dioecious, having both male and female plants and requiring both sexes to be present to produce seed. It's very hard to sex the plants at the seed stage so seed packets do usually contain both male and female plants which is hardly noticed by most gardeners because they eat the young plants before the flower and seeds develop anyway.

For the home seed saver this not very complex but slightly interesting characteristic combined with a wind pollination habit that requires isolation of five miles or more to ensure purity means that plants need to be caged or bagged in mixed groups - two males for each four females - during seed production. It's easy enough to identify the sexes, the males are bit fluffy and the females have sturdy stems with big seed capsules but if you're growing specifically for seed you may need to plant in groups that can be easily contained, perhaps removing any excess male plants before you do.

Unless you happen to be five miles away from civilisation like me! I can't guarantee that no rogue spinach pollen will drift in from the village but given the distances and tall barrier of beech trees on most sides I think my Bloomsdale will be driven snow this year.

artichoke harvest

I took a harvest from the artichokes this morning. There are two seed raised plants which have proved hardy enough to survive though a couple of winters now. I think the variety was supposed to be Green Globe but as with many seed raised plants some considerable variation was shown. The smoother tidier looking heads are as Green Globe should be but the spikier, almost lethally thorned, sort is clearly a throw back to a more original type. It's still just as edible but the thorns need careful removal before serving, I use kitchen scissors to trim the leaves when the artichokes are to be served whole.

I made a jar of marinated artichokes from most of these, the recipe will probably appear on the Stripey Cat in about a week, when I've had a chance to sample them.


Robert Brenchley said...

Unless there's a farmer locally with an entire field of spinach, youve no need to worry about cross-pollination beyond twetny yards or so. the distances are intended for farmers not gardeners.

I hope we don't get any Smith periods for a while, but I'm experimenting with TPS from a variety which resists the US strains of blight. We'll see whether it survives ours!

Catofstripes said...

Hi Robert, I'm sure you're right and for my own purposes, spinach is spinach and as long as it doesn't revert to a wild type I'm happy enough with it but I do think it's important to pay attention to variety purity, one) because I sometimes swap seeds and wouldn't like to offer something that I felt wasn't a good example of the variety and two) because I have very little income here and hope one day to have a small revenue stream from raising some seed varieties. Knowing about distances and methods of pollination is part of my required education for that. Professionalism is an ambition.

Good luck with your blight resistance testing.