Crops in focus: brassicas

Which are what most people are harvesting now. I still have exactly one floret of purple sprouting broccoli, so I hope the rest hurries up a bit. First to clarify a confusion: broccoli is an over-wintered crop but calabrese produces its crop the same year, before the winter. Both are brassicas as are cabbage, kale and cauliflower - and they are all part of the mustard family, oddly enough.

The ideal brassica bed needs both nitrogen and humus so the addition of manure in autumn will accomplish both. Dig over the soil and then add a barrow load of manure per square metre to the land. Leave the manure over the winter to give the worms a chance to take some down into the soil. But because adding the manure will have had the effect of making the soil more acid and because brassicas don’t like acidity, it’s best to test pH to measure the acidity and add the appropriate amount of lime to take the level up to 7.0.

Seeds are usually sown in spring, planted out in early summer to give a crop the following February/March through to May. There are early, mid-season and late varieties if you want a long harvest. Wind rock can damage the plants, especially through the winter, so try to find a sheltered site, earthing up around the stems for several inches keeps the plant stable and you may want to stake the tallest varieties – we certainly do!

You’ll also want to keep them netted, pigeons will go for the young plants especially in winter when other food is scarce. Broccoli is a slow-growing crop and it may benefit from a liquid feed, high in nitrogen, in the spring as the heads begin to form.

All brassicas are at risk of clubroot, caused by a soil borne organism which produces cysts which lurk in the soil until a suitable host is available to infect, starting the cycle again. The cysts can live for 8 or 9 years. Even worse, it is easily spread. The first sign is a wilting of plants, especially in dry weather. The roots have swellings and look knobbly. If you have a clubroot problem - start your brassicas off in modules using sterile compost to which you’ve added a small amount of lime – keep potting on until they reach 5 inch pots. Clubroot thrives best in acid wet soils so ensure your brassica bed is well dug with grit or other material to allow free drainage and take the pH up to 7.5 or even as high as 8.5 by adding lime Before planting, dig a hole at least 30cm deep and wide which you dust with lime to whiten the soil in the hole. Fill the hole with bought in multi-purpose compost and then plant your brassica in this. And burn your brassica plants when you’ve harvested, so you don’t return any clubroot to the soil.

Labels: allotment-brassicas, allotment-broccoli, allotment-crops

Winter colour on allotments

What colour would you call this path? I have to say that when I saw it last week I felt a bit … dazzled? It just seems too garish for an allotment, to me at least. Still, it’s not my path so I don’t have to worry about it.













On the other hand, a colour I’m particularly happy to see is this lovely shade of purple which is glowing gently from the brassica corner – my purple Brussels sprouts didn’t blow at all and look lovely, tightly-budded little beauties that they are. I wonder why though? Do they take up nitrogen better than the green ones or perhaps they need less of it? I have no idea why they stayed as tight as buttons while the green Brussels sprouts with which they are inter-planted went off in big rose-like blowing frenzies. Does anybody else know what the answer is?

I’ll tell you what though, that dried blood did the trick. Once I’d picked off all the blown sprouts (and stir fried them, waste not, want not!) and sprinkled dried blood and watered it in (and what a stinking job that is) the sprouts higher up the green Brussels stems are just as unblown as the purple ones. Lesson learned for next year: stake better, lime more, and ensure that if they start to blow I take remedial action on day one.

I suspect that to keep the colour in the purple Brussels they will need to be steamed rather than boiled, so I might try a test run this weekend when I go up to get some more Jerusalem artichokes to make soup. I want to have purple vegetables on our Christmas dinner table, and I’m hoping for both purple sprouting broccoli and purple Brussels sprouts. The first broccoli floret has appeared, so the timing is looking good.

Still no frost to kill off the whitefly though … but lots of rain to wash them away. And we lifted our bean frame this week, so that we can put it in its new location once we’ve manured the soil where it’s going to go. If it every stops raining, we might be able to get on with things a bit!

Labels: allotment-brassicas, allotment-brussels-sprouts, allotment-paths, allotment-whitefly

Jerusalem Artichokes, brassicas and parsnips

These are our ‘overflow’ parsnips – we didn’t have enough space to plant all the parsnips we wanted, so we stuck in a row along the front of our runner beans, knowing that the soil wasn’t ideal (nor was the position, the leaves went over the path and got walked on a lot, and they were a nuisance to step over to get to the beans – most of the bean pods we failed to harvest were low growing ones we couldn’t find amongst the parsnip leaves) and they have come up rather forked but we’re still happy with them, as we haven’t even begun to harvest the ‘real’ parsnips in their properly prepared bed. Hope they are a bit straighter!

Steve Godley emailed thus: I have a block of brassicas containing brussels sprouts, cabbages, cauliflowers and curly kale. It is netted with ½” mesh netting against the pigeons but everything is covered with whitefly. At home in the garden I watch the bluetits and their friends searching through the treetops for similar insects I have just set some 2” wire mesh on two sides of the enclosure in the hope that smaller birds (bluetits and the like) will get in and feast on the whitefly. Has anyone already tried this? Or is there another way to get rid of whitefly?

Well, the only remedy I’ve found for whitefly is soapy water sprayed on at regular intervals. I know that all the gardening books say that whitefly does little or no harm to a plant, but a proper infestation will definitely stop the brassica growing properly, and it is horrible to have to wash thousands of flies (and eggs) off the convoluted leaves of something like curly kale. What we need is a good frost to kill the little blighters off, but no sign of that so far.

Jerusalem artichokes – the jury is still out, but the jury foreperson (me) is inclining towards a ‘guilty’ verdict. They definitely to induce wind, which is rather embarrassing if you spend all day with the public, as Himself does, but also, we weren’t thrilled by the flavour. I cooked three or four in a beef casserole and the results were truly flatulent. We’ll try twice more and if we don’t like them any better the third time, we will not be eating them again!

Labels: allotment-brassicas, allotment-jerusalem-artichokes, allotment-parsnips, allotment-whitefly

Allotment problems – blown sprouts

Just to prove it never rains but it pours, we’ve got blown sprouts. It seems there could be two causes, either