3 Herbs to Overwinter in your Garden to use in your Kitchen Edible Garden

Choosing just 3 Herbs to overwinter in your garden makes it easier for those of you who haven’t considered this gardening “challenge” before. Keeping herbs growing throughout the winter months so that you still have fresh herbs for cooking and for brewing tisanes does not have to be difficult.

When talking about these 3 Herbs to overwinter in your garden, I am referring in particular to the British climate. But the suggestions and growing instructions will be valid for other temperate climates and zones.

Climate, Temperature and Microclimates

The climate has an effect on the plants we can grow in our gardens. That is self-evident. But it isn’t as simple as it may at first seem. Let’s have a brief look…

The United Kingdom has temperate maritime climate. Generally speaking, this gives us cool winters and warm summers. The warming effect of the seas, in particular the Gulf stream running alongside the western coastline, keeps the average winter temperature higher than for other countries at a similar latitude.

When we look at the UK in relation to the USDA Hardiness Zones, the British Isles ranges from 7a to 10a. The USDA is the United States Department of Agriculture. Their zones are just one of the ways to work out how likely herbs and tender perennials are to overwinter in your garden.

For example, the Scilly Isles off the south western tip of Cornwall are zone 10a. This is on a par with parts of Florida. However, the number of daylight hours that the Scilly Isles receives in winter is much less than that enjoyed in Florida.

A whistle-stop tour through regions, areas and localities takes us onto microclimates. This is about your individual garden, and specific areas within your garden.

Microclimates and your garden is a topic we look at in some detail in Plews’ gardening courses, and I have discussed it in other blogs. The relevance here is this. Does it allow you to overwinter in your garden herbs which would otherwise die off in autumn?

For example, Lemon Verbena, Aloysia citrodora, is a tender perennial. It may however, overwinter outside in your garden if you live in Cornwall. Or have a sheltered, South-eastern England garden. Or indeed, live on the North-west coast of Scotland and benefit from proximity to the gulf stream.

3 Herbs to Overwinter in your Garden – which three?

Good question. And we haven’t even defined garden…

Some of the easier herbs to overwinter in your garden if you live in the UK are going to be: –

Bay
Chives
Marjoram
Mint – spearmint
Parsley
Rosemary
Sage
Thyme
Winter Savory

But just because these herbs overwinter doesn’t mean that they’re going to be growing above ground so you can use them! Mint is not difficult to keep growing over winter, but does require a bit of effort. So I thought we’d start with 3 herbs that are useful in the kitchen but easy to keep growing in your garden all winter.

Which brings us back to defining garden. The following 3 herbs – Chives, Parsley, Rosemary – will all grow in the ground in your borders. This could be in a kitchen garden, herb garden or mixed in with your roses and ornamental plants. They will also grow in raised beds, containers and pots. So you could have the main plant growing in the ground, watered by the rain and a smaller version in a pot in a cold frame. As these herbs are suitable for container growing, you could have fresh herbs even if you only have small courtyard or balcony to garden in.

3 Herbs to Overwinter in your Garden – Chives

Chives, Allium schoenoprasum, are likely to die back except in sheltered areas and microclimates. They’ll sprout up again in the spring, but tough luck if you wanted to add them to your omelette in January. Growing a clump of chives in a pot so you can give them cover in the frosty months may help to keep them growing.

Speaking personally, this has worked some years and not others. The variables have altered: in a container herb garden, greenhouse, windowsill, cloche, hard winter, mild winter, North Wales, Southeast England, etc. Typically, I have noticed that an unknown strain I inherited with my allotment is the hardiest and will overwinter on a more exposed site.

However, Welsh onions, Allium fistulosum, known as chibbles in Cornwall, can and do overwinter. The variety Allium fistulosum ‘Siberian Everlasting’ is winter hardy across the UK, as you’d expect from the name.

Eat both the hollow leaves and the bulb ends. Remember to always leave some in the ground so the plant can clump up and provide more chives for your table.

Chives also tolerate shade – a useful herb when you have a north facing back door.

3 Herbs to Overwinter in your Garden – Parsley

Are you surprised at my choosing Parsley? Many people think this is an annual herb. It is actually a bi-ennial, so it lives for two years.

There are two popular types of this well-known herb. Curly Parsley, Petroselinum crispum, and the flat leaved variety, Petroselinum crispum var. neapolitanum, Italian Parsley. Both will overwinter.

You can overwinter spring sown Parsley that you’ve been picking from all summer long. These plants will have developed tap roots and should be hardy even with some frost and snow.

A more reliable method for lots of fresh tasty leaves overwinter is to sow Parsley in August. These younger plants will need frost protection. However, they will still be providing you with fresh home-grown Parsley in spring when it’s expensive to buy in the shops!

3 Herbs to Overwinter in your Garden – Rosemary

An established plant of Rosmarinus officinalis, common Rosemary, is your best bet in the colder regions of the UK. Until established, by which I mean mature, not straggly, you may need to give it some protection if there’s a heavy frost. Rosemary is a Mediterranean plant, particularly found in coastal regions. Perversely it’s not so much the UK’s winter rain and frost as the summer rain that is not good for it.

Generally speaking, in a free draining soil, most Rosemary cultivars will happily provide you with fresh herbs throughout winter. So if you have a young rosemary plant in a heavy clay soil, keep an eye on it overwinter.

You could lift the plant temporarily and improve the ground. If you dig up the Rosemary with a decent root ball of soil, it would be fine in an empty compost bag or bin liner while you prepare the soil. Pop it into a greenhouse or shed and stand on a gravel tray if it’s in the bag for any length of time.

Dig in a good amount of horticultural grit and a little organic matter into the soil. This is to improve the drainage. Then replant your Rosemary.

3 Herbs to Overwinter in your Garden – general points

Although evergreen herbs continue to grow over the winter months, they grow much more slowly. So pick your fresh herbs as you need them; which is the point of growing them yourself, anyway.
This slowing down applies to both those herbs grown outdoors and those grown under protection.
The aromatic foliage of herbs derives its scent from the production of volatile oils. As growth slows, so too does this production.
Frosted leaves will lose some of their flavour. You may prefer to compost badly frosted foliage rather than use it in cooking.
Well-watered, turgid herbs are less likely to suffer from permanent frost damage. Although you shouldn’t overwater them, if you’re regularly picking evergreen herbs in the winter be sure they have enough to drink as you’re stimulating the growth hormone.

Herbs in pots and containers

If you have transplanted the herb into a pot for winter or were growing it in a container to begin with, you may need to give the roots frost protection by wrapping the pot.
You may also want to place the pot in a sheltered spot. Combining a number of pots in a group not only looks better but gives the individuals some protection. They form their own little microclimate.

If you would like more help with growing herbs in your garden, why not get in touch? Plews offers Gardening courses and lessons, planting designs for herb gardens and more, so you can get the most pleasure from your garden.