Winter is not usually associated with growing edible plants and why would it be? Growing conditions are generally awful with consistently low temperatures, frozen soil, and shorter days with lower light levels – that is if the sun ever actually comes out.
You may be surprised to find out there are a few salad plants that will grow over this period that are certainly worth a try, and not only will they grow for you they will bring you some fantastic produce right at the begging of the new year when there is nothing else around.
You wouldn’t believe that a plant associated with such soft succulent and tasty leaves would have the slightest chance of surviving a British winter but there are a number of rock-solid varieties that will. The most popular of these in the UK are ‘Winter Density’- perhaps the hardiest of all winter lettuce - and ‘Winter Gem’ – a cultivar of the enormously popular 'Little Gem' - both of which can be grown with only the minimum of frost protection. However, look out for ‘Rouge D’Hiver which is old French strain dating back to 1880. Its name translates as 'red winter' and as it suggests it has a striking red and green colouration with an upright, semi-cos habit..
Sow your winter lettuce seeds any time from August up until the middle of November. Good drainage is essential for growing winter salad as the seedlings will simply freeze if left standing in pools of water. Choose a sheltered, sunny position as this is important when protecting seedlings from cold winter winds..
When sowing spring lettuce seeds directly outside choose a sunny site but depending on how severe or mild your winters are you may need to give them the protection of a small poly-tunnel. This will definitely be the case if you are growing in Northern Europe. Try to keep soil no more than moist as this will help to ensure that your seedlings do not get too cold or wet.
.If you are starting them off into seed beds, sow the seeds very thinly in ½ inch deep drills but leave about 6 inches between each row. If you are sowing them directly into the open ground then leave between 10 and 12 inches between rows. To avoid having a glut of lettuce and to ensure that crops are regularly coming into harvest, make successive, smaller sowings of lettuce seeds, at 4 week intervals depending on how much you intend on using.
Once the seedlings get to about 2 inches high they can be thinned out to leave a gap of about 6 to 12 inches between each plant- depending on the overall size of the variety grown.
.Winter salads traditionally have a strong flavour that can sometimes taste a little bitter. If you find that your salad leaves are not to your taste, try blanching the leaves. This can be done by covering the plants with an upturned flowerpot Leave like this a few days before harvesting, and the leaves will become paler and less bitter. Alternately you could grow the entire crop under horticultural fleece. Not only will this reduce bitterness it will give added protection against the cold.
Depending on the weather harvesting can begin from January onwards. As a rule of thumb, head-forming lettuces are ready to harvest when their hearts are firm. They can be cut at the base, leaving the roots and stem base in place, which can go on to produce a second (smaller) head of leaves.
Loose-leaf lettuce varieties are best harvested gradually, removing a few leaves at a time or cutting them back to 4in. They will soon begin to sprout again which is why they have earned them the name as a 'cut-and-come-again' crop.
As the plants bulk out it is common practice to harvest every other one as needed. This will give the remaining plants more room to grow.