Over-winter herbs to add soul to warming winter cuisine. With a little bit of care you can keep a fresh supply growing through frosty winters.
While it’s goodbye to summer favourites like basil, mint and chillies there are many other herbs that can happily survive through winter if they are cared for correctly.
Robust culinary herbs like thyme, oregano, marjoram, parsley, chervil, and even sage, are hardy enough to survive our dry, cold and even frosty winters provided you find a sunny, sheltered spot for them.
In winter, herbs need at least four hours of sun a day, and they should be kept out of cold winds, especially if the soil becomes too wet. The best way to ensure this is to pot up a few of your favourite herbs and move them as the sun moves.
Sage is probably the least hardy of the herbs but leaves can still be harvested up until the end of July even though they get smaller and smaller. Sage is also the most sensitive to over watering so the potting soil should drain well. In spring they will sprout again and throw up lovely spikes of mauve flowers.
Sage, parsley and thyme also have medicinal properties for treating winter ailments like coughs, colds, and sore throats. By adding hyssop, which has expectorant properties for relieving bronchitis, and yarrow for lowering fevers, it is also possible to have home-grown winter remedies on hand.
If there is not an area in the garden that receives consistent winter sun, then containers are the best option. Choose containers that are at least 20cm in diameter (larger is better) have drainage holes and are deep enough for the herb’s roots to develop. Use a normal commercial potting soil that drains well.
Generally potted herbs only need to be watered one or twice a week in winter, preferably in the morning. Check the soil moisture levels daily because the soil should not dry out completely. Herbs don’t like wet feet so don’t put saucers underneath the pots.
Another option, especially for apartment dwellers, is to grow herbs on a windowsill that receives winter sun.
Ideally herbs are meant to be grown in full sun, in well-drained soil. However, that doesn’t mean you can’t grow them on your windowsill. You just need to adjust your expectations.
Don’t expect them to act like perennials. Treat them like any other flowering pot plant that you buy for the house and discard when it has finished flowering.
The same applies to herbs. Use them and when they start looking sickly, turf them out and buy a new pot. It doesn’t mean you have failed as a gardener.
The reason why such herbs have a limited lifespan is that the windowsill pots are actually too small for sustainable growth and they are probably not getting enough light. It is also possible that the air may be too hot or steamy and that the temperature changes are too extreme.
Try grouping the herbs close together so that the transpiration from the massed leaves creates some humidity. It’s also an idea to stand the pots on a layer of gravel as this helps retain moisture and keeps them cool without the plants becoming waterlogged.
Their life can also be extended by feeding with a liquid plant food at half the strength. Also, don’t over water. Once a week should be enough.
Keep the soil feeling slightly damp, but not sodden or bone dry. Check that they aren’t sitting in a saucer of water. This causes the roots to rot and the plant to die very quickly.
When harvesting collect small quantities at a time and always leave two growth points on the twig for re-shooting. Instead of cutting at random rather use the opportunity to pinch out or prune the plant to encourage bushiness
Once picked handle the herbs as little as possible because the subtle nuances of flavour are lost if handled or allowed to wilt.