November polytunnel
It can be tempting to ignore the polytunnel for the next couple of months, especially if the weather is miserable. If a complete clear-up, plant-out, scrub-down and eviction of old plants took place in October, it might be possible to do little work other than harvesting in November, but few gardeners are that organized. Even in the coldest months, there are plenty of things that can be done to get the best out of a polytunnel. Get out there! Keep tidying! Try sowing broad beans, planting out peas or using water barrels for warmth. A polytunnel offers protection from the elements and on bright days it can be quite warm. Put in a few hours per week in November and maybe December will be an easier month.
Weather report
If the winter months are in any way true to form, November should bring an abundance of rain and a few gales or, at the very least, some strong winds. Bitterly cold weather, hard frosts and the first snow falls are also possibilities. Soil in the poytunnel will be slower to cool down than that outdoors, but once it drops below 5˚C/41˚F plant growth will stop.
Bring water barrels into the polytunnel
Sow broad beans and peas
Plant out September and October sowings started in pots
Remove all dead and diseased foliage
Clear summer crops that have stopped producing
Check for storm damage
Start feeding the soil
Water very sparingly
Stake tall plants
Plant a grape vine
Time to sow
Broad beans
Mangetout peas
Winter lettuce
Mizuna
Mibuna
Rocket
Mustard greens
Early carrots
Keep planting out
Late sowings
Anything that is sown in November will grow very slowly and may not give a crop until well into the spring. However, these sowings will still give crops much earlier than similar sowings outdoors.
• Try sowing broad beans and mangetout peas in early November (if you have not done so in late October) and be the envy of other gardeners next spring. These plants should start to crop in April – about a month sooner than those sown outdoors. You can also sow winter-hardy, podding peas, but somehow these don’t seem to crop any earlier than ones sown under a cloche outside.
Choose a hardy variety of bean, such as ‘Aquadulce Claudia’ or ‘Super Aquadulce’, and sow individual seeds in 8cm/3in pots. A cold-tolerant mangetout pea such as ‘Oregon Sugar Pod’ can be sown at four seeds per 10cm/4in pot, or more if you are using larger tubs. Lay seeds on the surface and push them down with a finger to the first knuckle joint, before covering with compost. Sow more seed than you need in case some fails. Cover with a layer of bubble polythene to give the best chance of germination. Don’t provide any extra heat, as this can lead to weak plants that will not survive well in a hard winter.
Direct sowing in the soil is also an option, but always put a few extra seeds in pots, or at the ends of the row; these can be transplanted to fill gaps. Watch out for hungry mice and rats, who will dig up seed and eat it.
Top Tip
I find that putting pea and bean pots in a large, clear plastic storage box (inside the polytunnel) works really well. It keeps slugs and mice at bay as well as providing a small bit of extra warmth.
• Rows of rocket, mizuna, mibuna and mustard greens seem able to survive temperatures as low as –7˚C/19˚F and still bounce back to produce prolific crops. Sowings in November will grow slowly, but should be ready for picking in late winter or early spring. Sow all these crops directly into the soil, as they do not transplant well.
• Winter lettuce can still be sown, but it’s worth starting the seed off indoors. Put pots on a window ledge in a cool room, so that seedlings don’t grow too ‘soft’. Harden off before planting out in the polytunnel when seedlings are 3–4cm/1¼–1½in tall.
Top Tip
In a mild winter you might have success with November sowings of early carrots and kohl rabi. Nothing is guaranteed, but it is always worth a try if you haven’t made earlier sowings and you want a few extra crops.
Water barrels for warmth
If there was no frost in October, there will certainly be some in November. Plants should be frost free in the polytunnel, but many won’t like the low temperatures. To raise temperatures slightly, it’s worth filling a couple of barrels (or dustbins) with water inside the polytunnel. These will warm up with the heat of the sun during the day and slowly release heat through the night. The overall effect may be small, but any gain at this point of the year is worthwhile.
NOTE: A barrel will also be a handy source into which you can dip a watering can. Hosepipes may be frozen, or the outdoor water supply too chilly for sheltered plants.
Try sowing carrots in a large pot
Planting out
• Late sowings of spring cabbage can be planted out in early November. These will be ready to eat in late April or May. It might not be worth doing such a late planting in a small polytunnel, as you will need the space for summer crops before the cabbage has formed good heads.
• Winter lettuce is still worth planting, even in a small space. This will give good pickings next March or April, especially if you use the leaves while the plants are still small.
• Spinach and kohl rabi sown in trays last month should be planted out as soon as possible. Young roots need a little time to establish themselves in the soil before really low temperatures kick in.
• Oriental greens, sown last month, can grow thick and fast. If plants need more space, thin and transplant a few seedlings.
• Mustard greens and kales certainly suffer little harm from transplanting, so it’s worth a try. Remember that this crop is primarily intended for picking while the leaves are small and sweet.
Tomatoes
Thin-skinned varieties may split as they ripen. Such fruit is still perfectly edible if used the same day. Moulds will grow in the exposed flesh if split fruit is allowed to fall or sit on the plant for several days. Small plum varieties seem to have slightly thicker skins, which don’t split so easily, so they may give sound fruit for the longest time.
In a mild autumn, plants can grow on into December. They won’t produce a lot of ripe fruit and the taste won’t be quite the same as a summer sun-ripened tomato, but there is something satisfying about picking tomatoes from the polytunnel this late in the year. The downside of this is that any diseased foliage and fruit hang around for longer than is really sensible. To give the soil a chance to recover, it’s best to pick all fruit (red, green or in-between) as soon as growth and ripening stop. Remove plants and be sure to scour the soil for any dropped fruit and leaves, as these can carry disease through into the next year’s crop.
Top Tip
If you have used canes or poles to support plants, remove these with care. A sudden upward jolt, as you pull them out of the ground, can damage the polythene.
Remember that you don’t have to clear all plants on the same day. Leave the ones that are still cropping and remove the ones that have finished. Burn haulms if they are diseased, along with any fallen leaves; otherwise add them to the compost heap.
Bowls full of green tomatoes will ripen on a window ledge if you put one or two red ones in the bowl to speed up the process.
Top Tip
Don’t compost any fallen or spoiled tomato fruits. This can lead to a host of seedlings carrying disease into next year.
Peppers
Peppers will be enjoying their swan song this month, as they try to ripen through the shortening days. It’s worth allowing peppers to ripen on the plant, even if the leaves look tatty and some start to drop. Fruit stays firmer this way and may even ripen in December, if the weather isn’t too cold. Pick as needed early in the month, but harvest the lot if temperatures fall below 0˚C/32˚F. If plants freeze inside the polytunnel, the leaves will blacken and fruit will spoil.
Harvest all chilli peppers once they stop ripening. They freeze really well and they also dry if left on a plate in a warm room. Try freezing half and dry the rest – both forms are equally useful. Dried chillis keep for months if put in a screw-top jar.
Once picked, sweet peppers can finish ripening on a sunny window ledge, but use them quickly before they become too soft.
Ripe chilli peppers can be frozen or dried
Potatoes
Second-cropping varieties, planted in the summer, should be covered with a few layers of fleece. Even so, they will not survive too many frosts. The leaves and stems will turn brown, but the tubers should be safe and sound in the compost beneath. If you are saving these for Christmas, leave them undisturbed and they will lift from the compost as fresh tasting as any early spud.
Lettuce and salad leaves
Summer lettuce varieties may still be growing well, but it’s worth picking these before they reach full size. If you leave them to grow bigger, they will start to rot as temperatures drop.
In a mild autumn, cut-and-come-again crops such as mizuna and mibuna can grow very fast. Pick leaves regularly; otherwise the plants will flower and the crop will finish much earlier than it should.
Top Tip
If you are faced with a row of large floppy salad leaves, use scissors to cut them back. This will encourage new growth and will postpone flowering for a few more weeks.
Strawberries
These should be outdoors in pots, but don’t ignore them altogether. Check to see that the plants are healthy. Cut off any discoloured leaves, nip out any errant flowers and top up compost if it has settled too low in the pots. They plants will come back into the polytunnel in a few weeks’ time and you should look after them in the meantime.
Winter winds
Gales can be devastating at this end of the year. Check the structure of the polytunnel regularly, especially if there are any strong winds. Fallen branches or flying pieces of debris can puncture polythene. Pre-empt this by cutting overhanging branches and weighting down any materials that might take flight.
Remember that if wind blows straight into a structure, it must have a way to get out.
Top Tip
Doors can blow open if latches are rattled for long enough. Put a heavy weight against the outside of the door to stop this happening.
Feed the soil
A healthy soil will grow healthy crops, but a lot is expected from the borders in a polytunnel. When one crop is lifted, another goes in, and constant demands are made on the soil. The borders don’t contain an endless supply of nutrients. Although you can apply liquid and dried feeds, the soil will eventually run out of steam if it doesn’t get a good bulky feed such as manure, compost or seaweed from time to time. November is a good time to do this: beds aren’t so jam packed and there is plenty of time for the material to break down and be incorporated into the soil for the year ahead.
Spread the manure or compost around growing plants, or make a pile and spread it out as any patch clears. You can always dig it in at a later date. The important thing is to get a good bulk of lovely organic material into the soil.
NOTE: You can buy compost and manure in bags if you don’t have access to a fresh supply.
Feeding the soil
Watering tips
The need for watering should be minimal in November. The water table rises in the land surrounding the polytunnel and borders should stay damp enough through the next few months. An occasional sprinkling of water will be required, but not much more. Containers will still need watering, as will any bed that is raised well above the outdoor soil level.
Water salad crops carefully. Too much water will make lettuce susceptible to grey mould, but too little water will make leaves bitter.
Staking tall plants
Tall plants, such as broccoli, kale or sprouts, need staking when they are grown in a polytunnel. They may not have to withstand the ravages of a winter gale, but plants can become top heavy. The whole plant can fall over and if roots are broken or pulled up, growth will be set back. Drive a stake into the ground and tie the stem to this at a minimum of two points – this prevents breakage across the tie.
Staking tall plants
Plant a grape vine
Vines can be rampant growers, so it’s unwise to grow one in a tiny polytunnel, unless you grow it in a large pot and restrict growth to 1m/39in high. In a large tunnel, however, a vine trained upwards and along the ridge can do spectacularly well.
Ideally the vine should root outdoors and the stem is then trained inside. This can be done through a small hole in the polythene, with all edges of the hole securely taped. Alternatively, plant the vine just outside a door and train the stem around the door frame. This might leave a gap where the door closes against the stem. You can avoid this by cutting a notch in a wooden door or frame.
Top Tip
Ouch! I can’t bear to make any hole in the polythene, even though I have seen it successfully done. I always prefer to wind the vine around a door frame.
Top Tip
Take a little time to select the variety of grape you plant. Ask what does well in your area and, if possible, sample some fruit from a mature vine. The vine will grow for many years. If you plant a small-fruited, seeded variety that is suitable for wine making when what you really wanted was a large, seedless, dessert one, you are sure to be disappointed.
Choose a sunny spot for planting the vine and preferably somewhere that doesn’t dry out too quickly. Dig a hole about 45cm/18in square. Half fill this with compost before planting and top up with soil. The growing medium should be heading towards a pH of 7, so if the soil is too acid scatter a little lime over the surface. Plant the vine at the same level that it grew in the pot it was purchased in and water well if the soil is dry. Prune to leave three or four strong buds.
A grape vine requires some work to produce good crops, but there is nothing that can’t be learned.
Holly time
Holly bushes are full of glorious red berries in November, but it won’t be long before the blackbirds and fieldfares turn up for a late autumn feast. If you want to keep any berries for Christmas, now is the time to act. Cut a few laden branches, with plenty of woody stem at the lower end. Push the cut stem down into damp soil in the polytunnel. There should be enough moisture to keep the berries fresh until Christmas time.
Enjoy the November harvest
Sweet and chilli peppers
Salad leaves
Lettuce
Oriental greens
Tomatoes
Spinach
Kohl rabi
Pak choi
Fennel
Beetroot
Some harvesting hints
• In a mild year, some summer crops will struggle into November. It’s unlikely there will be more than a few small courgettes, or the odd leaf of basil, but it can be worth leaving them to grow until they are killed by frost.
• The main pickings will be from winter greens, although late peppers and tomatoes can also put in a good show. Pick winter crops regularly but carefully. Growth will slow down through the winter and pick up again in the spring, by which time they will tolerate much harder picking.
• Lettuce plants from the same sowing grow at different rates at this end of the year. This is quite handy for spreading out the cropping season. Cut the biggest plants first, and always before they become bitter.