HOW TO OVERWINTER HERBS |The Garden of Eaden

selection of hardy herbs planted in the ground

How to overwinter herbs

After a year of harvesting your favourite herbs it's understandable that you would try and keep the established herbs you have rather than purchase another collection the following year and wait for them to grow to a suitable size before you can start harvesting. Of course tender species and cultivars such as lemongrass and basil will never survive outside in climates which experience freezing winters, but there are plenty of hardy herb species which with a little help and encouragement will easily pass through the winter unimpeded, ready to supply you with fresh grow as soon as spring appears.

In most northern European climates October will be the time to help prepare your herbs for over wintering, although you can probably wait until mid-November in the milder regions of England and Ireland. Cut herbaceous varieties such as marjoram down to ground level removing all of the woody sprigs so all that is left is a tidy carpet of young fresh foliage. Not only will this make your plants look a lot tidier, it will also prevent you from catching the sprigs under your nails when harvesting new shoots over winter.

How to overwinter herbs

Conversely, leave the pruning of woody herbs such as rosemary and sage until later. The leaves, although looking weather worn, will act as a protective barrier against the worst of the winter weather and insulate the dormant buds below. The old foliage can be pruned off in the spring once the danger of frosts has passed.

For a supply of fresh chives over winter dig up and split the clumps, potting them on into compost filled pots. Leave in a porch or cold frame and they will continue to produce fresh leaves throughout the winter. The same treatment will also work for mint.

Remove any dead leaves that may have fallen onto your thymes or other small evergreen herb's as this can cause fungal infection.

If the weather looks to be getting a little too cold then keep an eye on your bay trees. These will either need to be fleeced up or brought in undercover to a cold greenhouse or porch. This is for their own protection otherwise the top leaves will suffer cold damage turning them brown. It is just as important to make sure that any new grow in the spring is not knocked back by late frosts. This is particularly important for topiary bays as these dead patches will cause them to loose shape. However, should the worst happen, a solid trim and a good nitrogen feed in the spring should bring them back to their former glory by the end of the summer.

If you have planted out a specific herb border then the easiest way to ensure winter protection as well as extending the harvest season is to cover the entire bed in a purpose built or makeshift polytunnel. This can be put in place as soon as overnight temperature look to drop below 7 degrees Celsius and then removed in the spring as soon as the risk of late frosts have passed.