Updates from November 2011.
Updated 13th November
This posting is a celebration of some extraordinary warmth which makes it hard to realise that winter is just around the corner. Growth has been strangely abundant for the time of year and I m picking so much salad from outdoor plants which normally, at this time of year, are growing only slowly and with leaves of lesser quality. Broad beans emrging already means they will be well established before winter begins, I just hope their stems won’t be too long and at risk from frost.
The pointed cabbage above makes delicious coleslaw. It was covered with mesh in July and August and has resisted the caterpillars since then: I am about to harvest it. One of my brussels sprout plants has just been partly defoliated by caterpillars after surviving through summer and autumn. The chicory is a lovely red radicchio for mixing with other leaves in salad; its heart resists some frost and is more likely to be damaged by leaves rotting from inside when the heart is fully mature.
The salads above were intended for winter more than autumn…. I am planning to cover them with a cloche, but there is no point in putting a cover on at the moment. Average temperatures in the past fortnight have been 8C by night and 14C by day, much above average. The purslane and endive plants in front have been harvested once, with a a knife and by hand respectively, around the edge in both cases.
Because there is so much salad outdoors, I have been keeping the tunnel salads in reserve in case of cold weather, but some are now so large that we are having to pick and compost their outer leaves. At least the plants are well established before winter!
Normally I grow lettuce Grenoble Red through winter indoors; also this year I am trying some Valmaine cos and also some Little Gem for picking as leaf lettuce. All the tunnel salads are still quite long stemmed and large leaved but new growth after picking will be more compact in the lower light levels of midwinter, and presumably the lower temperatures.
As we enter the year’s winter half, summer is hanging on and the garden is bursting with leaves and roots to harvest. Temperatures have remained mild, apart from slight ground frosts on three mornings in October and one small air frost.
Mild conditions help growth of winter salads and any October sowings should be benefiting. I am often asked, can salad seeds be sown in November? Yes they can (undercover only), BUT growth will be slow and little harvest, if any, can be taken until March, unless it is of tiny leaves, or winter is unusually mild. Whereas salad seeds sown by the end of September, as below, are starting to crop now and should give leaves through winter and until the end of April, although leaves are small in midwinter.
The main thing is that plants survive in good health and ventilation is important for salad: keep the greenhouse or polytunnel window and door open every day. My tunnels have mesh rather than plastic doors, allowing air at all times, day and night. If there is too little ventilation, even in freezing weather, stale air can lead to mildew, and lettuce can even rot through their stems.
Watering of winter salad needs to be as infrequent as you dare. I water every ten days or so through November and make sure that soil is fully moist by month’s end, then water much less. Last year because it was so cold, I did not water salad in the polytunnels between late November and early February. Over two months without any watering! A watering in mid February was then followed by ten-day waterings in March, and weekly in April. Weather affects the time period between waterings and if your soil is light, you will need to water more often, but go steady in winter, always making sure that soil is fully moist each time, to increase the time before another watering is needed.
Outdoors: last sowing, clearing, composting
If you have not already done so, there is still just time in early November to sow broad beans and garlic, as soon as possible. Don’t worry if you see no new leaves for two or three weeks, even two months in the case of garlic. Last year mine emerged in early January, from planting in October, and grew superbly. At this time of year, new sowings are making roots as much as leaves.
After sowing, beds can be mulched with a layer of compost or manure so that garlic cloves and broad bean seeds are well buried, at a level where soil is less cold and they are less easily pulled out by birds, or pushed up by frost: garlic can be two or three inches below the surface and beans up to six inches below although mine are about four inches down.
Other beds want clearing of crop residues and any weeds after last harvests are taken, then compost and manure can be spread. Sometimes I leave the leaves of leeks and carrots on the surface, spread compost on top of them and find that they have been taken in by worms by winter’s end. But there is a risk of encouraging a higher slug population when too many residues are left on the surface, so be careful on clay soil and if you are planning an early sowing of carrots. Keeping ground clear of weeds through winter helps keep slug numbers down, so that early sowings can succeed better.
Sometimes it is argued that bare soil in winter is a bad thing, “because of nutrients being washed away”. I disagree with this because in an organic garden the nutrients are not water soluble and hibernate through winter in healthy soil, compost, aggregations of organic matter, wormcasts and even in dead organisms in the soil, ready for eventual release next spring and summer when sought out by plant roots, in cooperation with soil fungi. I think that misunderstandings arise from the widespread use of synthetic nutrients (in fertilisers such as ‘growmore’) which are indeed water soluble and leach away in winter. Even some organic gardeners have been influenced by this and cover their beds with plastic to “conserve nutrients”. But compost is not plant food in the way that artificial fertiliser is: it is SOIL FOOD! Its nutrients may ultimately be the same but they become available in a different way.
My experience of three decades with bare beds in winter is emphatically that nutrients are retained in bare soil, and that this makes gardening much quicker and more successful in spring. Especially in comparison with the digging-in or covering of over-wintered green manures, which also tend to harbour slugs and weeds, then need time in spring to rot down and for their nutrients to become available to plants.
For winter, I recommend bare, weed free soil with a surface mulch of compost or manure, which is ready for sowing and planting at any stage from Febvruary to June, after simply knocking out any larger lumps with a rake. The surface does not need to be super fine and after one of my October courses, Lindsay Williams from Kent wrote a helpful piece:
“One thing I took away was how the soil looks given repeated dressing. The surface is quite rough and bumpy. I had a feeling that compost should be sieved, a tedious and back breaking job. But Charles does not sieve and sees benefit in this lumpy surface because it dissuades slugs, and is good for seeds and plants.”
Carrot root fly has been bad this autumn and I have just had to compost a third of the last harvest which were grown under mesh since July! It appears that the flies can crawl under edges that are not buried (mine were secured with stones at three foot intervals), or does anybody have more knowledge of this?!
Leek moth has also been abominable, so numerous that some gardeners are reporting total wipe-out. It seems the moth was laying eggs in May and June on leek plants in seedbeds, so the ypung plants had eggs and/or small maggots inside them when transplanted. So even if covered with mesh, to keep the moths out, there were maggots quietly eating away underneath the cover!
I have not used mesh and am so far disappointed with my plantings from leeks sown in an open seedbed. However it looks likely that three quarters of them are strong enough to grow well through winter, as the maggots have now pupated and are not eating any more. I did not cut leeks to ground level and find that mostly they do well without that drastic stem-cut.
I do have a GOOD RESULT from leeks sown in modules in the greenhouse in late March: varieties Swiss Giant for August to October harvest, and Autumn Mammoth (above) for harvesting now and through winter if it is not too cold. There is caterpillar damage to most plants, but they are large enough to possess some lovely shanks underneath the eaten leaves. Because these are grown from module-raised plants, their stems have not been buried at planting time or earthed up later, so the shanks are not pure white, but look how clean and light they are, and the flavour is good.