One of the perversities of our human condition is the desire for foods when they’re out of season. When our strawberries, asparagus and tomatoes stop producing at home foreign ones continue on the supermarket shelves till our next crops arrive regardless of their air miles. Many bewail this apparent waste of resources, others the lack of seasonality. The former critics forget the need for developing countries to sell us something- and surely fresh fruit and veg. are better than bush meats and drugs. The other complainants have a point as foods are more appreciated if they have been awaited for a long time. But these critics over-look the simple nutritional economics- surely it is better that people eat out of season, imported, fruit and vegetables than not. The recommended dietery advice of ‘Five a day’ is hard for many to follow, certainly easier with more variety. But home produced items are scarce in winter.
In the summer and early autumn we are faced with massive choice and gluts of almost everything. In winter through early spring we have rather little fresh stuff to choose from at all. No matter how skilful the gardener come the winter months the range of fresh fruit and vegetables we can have growing or stored shrinks remarkably. So it is a positive health benefit to be able to enjoy fresh crops grown elsewhere when we cannot sensibly grow them ourselves.
However, and even more since ‘global warming’, we should be careful not to import and buy in those things we should be growing ourselves. On either the large scale or personal an economic point is that those out of season imports are very expensive. In particular bags of picked mixed salad leaves flown by air. Which, luckily for us, are about the easiest things you can grow in the winter months.
Salads, especially young leaf ones, are intrinsically easier to produce than fruits or other crops, and packed with more mineral goodness. Fruits are harder to harvest out of season because most are perennial woody plants and so locked into the seasons. Given extra heat most still follow the day length and until we adjust that and the light intensity it is difficult to crop most fruits in winter. Though fortunately most of the Citrus naturally ripen at this time they have little other competition. Tomatoes have been intensively selected and such as Sub-Arctic Plenty can be cropped in winter under cover and cucumbers are not immensely difficult.
But salad crops are much easier because they are herbaceous and less locked into the season, or rather those bits we want are. Most salad crops grown from seed will germinate any time of the year given some warmth (excepting lettuce which will not germinate if it’s too warm). Although how these seedlings would do later would vary a lot. But for mixed leaf winter salads we don’t want the final result; we are after lots of small barely developed leaves. The smaller and softer the better. Especially the hotter ones such as Rocket and Chinese mustard greens where to be palatable they almost have to be grown under cover.
Many salad crops might be grown outdoors unprotected as most are reasonably cold tolerant. But then they grow slowly becoming tougher, bitterer, and are more prone to pest, weather and dirt damage. So they do much better in cloches, cold frames or in a greenhouse or plastic tunnel. And as many will not germinate reliably without a little extra warmth it really helps to have a small heated propagator to start them off in cells or plugs for planting out later. With this and either a large cold frame or unheated greenhouse it’s easy to have masses of fresh leaves in prime condition every day of the year.
Salad crops can be grown either directly in the soil under cover, or just as well in large pots. The latter are often more convenient and on very cold nights can be moved together for protection. In both cases continuous rotation is called for with new batches of seed sown every week or two so older plants can be continually replaced by fresh small ones. (In the soil ideally by a different type though in pots it can be by the same if the compost is changed.) The soil or potting compost needs to be in good condition, well enriched with humus and continually moist but never water-logged. I mix in loads of sieved garden compost but as so many weeds germinate from this I then dress the surface with sterilized soil (baked in my Rayburn oven) or spent clean potting compost. By planting through this layer it reduces the weed problem. I recommend you also keep a clean sterile layer on top of the soil as it not only reduces the number of weeds but prevents a lot of diseases started by dirt splashing onto leaves. In pots fill three quarters full with any reasonable potting compost then top off with a sterile quality one again to prevent weeds and diseases.
Good hygiene is needed and always remove any mouldy or fuzzy bits as soon as spotted as infections spread rapidly in winter’s slow growing low light conditions. Water from a dirty butt is more likely to carry diseases than tap water. However the latter is often much colder and could chill so needs warming up a bit first. In either case leave the filled watering can in a warm place over night so it’s nicer for the next day. In pots and containers never let the plants stand in water in saucers as in cold conditions the roots soon rot. Wetting the foliage is also risky so watering needs be done carefully. Feeding, if thought necessary, must also be done carefully or the roots may die from ammonia released by the excess fertilizer breaking. All this said though there rarely are many problems other than weeds and a bit of mould.
Without doubt the most widely grown winter salad is loose leaf lettuce. Available in red, green and crinkly these give usable leaves very quickly from seed, and whole thinnings from the initial cells or pots. Though there are winter hearting lettuces those take so much more time and space they are barely worth considering. For those who like the bitterer tastes you can also sow the lettuce like endives and leaf chicories; though these are slow to bulk they are worth having as seedlings in pots. Rocket is one of the fastest and most useful salads, and very easy in pots. Indeed sow it every week and throw away the old plants quickly as they soon get hot and tough even if cut back. There are many named varieties of Rocket but they vary little and it is worth letting a plant or two grow on for seed as so much gets used. Wild rocket is different, tougher but also hard to eradicate, as is Turkish rocket which gives very early leaves in late winter. Spring onions, ideally of a winter hardy sort, are slow growers and always useful so they need sowing thickly and thinning as needed. Parsley will only grow if warm but can be started off thickly sown in pots in the propagator and used as small seedlings rather than grown bigger. Celery can be similarly started off and utilised. Chervil likewise, and like parsley and celery this is also useful in cooked dishes. Not widely known but really worth having are Lamb’s lettuce, Valerianella, and Miner’s lettuce, Claytonia/ Montia perfoliata. The former, also known as Corn salad, also makes a good green manure flowering like small forget-me-nots in spring, it has bland succulent leaves. The latter is a weed of cool moist places and disappears in warmer drier times making it the most fantastic winter ground cover and green manure. Loved by chickens and children it is a great unknown and good used in quantity in salads or as a spinach. True spinaches can be grown for baby leaves- but choose a variety good for winter conditions such as Lazio or Samish.
Becoming very popular for winter use are Chinese greens- the chunky Pak-chois are intended for cooking but small leaves can be used for salads. There are many other Chinese greens such as Mizuna,s all have a very mustardy taste unliked by some but relished by others- try them with a honey, ginger and balsamic vinegar dressing. The edible chrysanthemum is another Chinese plant and the young leaves are used in stir fries but can also be added in moderation to salads.
Radishes, unless really loved, take too much space for too long. Baby beet and baby turnips are a better bet as their small leaves are good in themselves. Carrots for eating small and fresh can be grown in deep pots- though they are slow.
Of course all culinary herbs such as sage, rosemary and thyme, can add variety to a salad and pots of these may be worth bringing under cover for softer more palatable growths. Mint and chives are definitely worth digging up, potting and bringing under cover for forcing fresh leaves. And if you are really keen then roots of chicory, dandelion and asparagus can all be potted up, kept in the warm and dark to produce blanched shoots in only a week or two. Only mustard and cress are quicker, but they do not need pots of compost doing well sown on moist tissue paper in small trays. But that is less like gardening and more like sprouting which is another subject entirely.