Making a Simple Sage and Thyme Infused Oil

Why Sage and Thyme Belong Together

Sage and thyme have grown side by side in British herb gardens for centuries, and they make a natural pair. Thyme brings a warm, earthy, faintly medicinal note; sage adds depth, a whisper of pepper and a soft, almost velvety finish. Infused together in good olive oil, they create something neither could manage alone — a golden-green oil that tastes of late summer and does quiet, useful work in the kitchen.

Both herbs are generous infusers. Their leaves are packed with aromatic oils, so they give themselves up to warm oil readily, and both keep their character well once dried. That makes this one of the most forgiving projects in the herbal calendar: no fermentation, no fiddly chemistry, just gentle warmth and a little patience.

There is a wellbeing dimension too. A spoonful of sage and thyme oil stirred into a dressing on a grey February evening feels like a small act of caretaking. Both herbs have a long folk history as winter companions — thyme for the chest and the spirits, sage for the throat and the digestion — and while a salad dressing is not a medicine, using your own infused oil does connect the garden to the plate in a way that shop-bought bottles never quite manage.

What You Will Need

• 50g dried sage — rubbed, loosely packed, and genuinely dry. If it bends rather than crumbles, it is not ready.
• 50g dried thyme — the common garden thyme is ideal; lemon thyme gives a brighter oil.
• 500ml olive oil — a plain, mid-range extra virgin works best. Save the expensive peppery bottles for the table.
• A clean 500ml jar with a tight-fitting lid, plus a second jar or bottle for the finished oil.
• A square of muslin, a fine sieve, and a funnel.
• A bain-marie, a heatproof bowl, or a slow cooker on its lowest setting.

Choose dark glass for the finished oil if you can, or simply keep a clear bottle in a dark cupboard. Sterilise your jars by washing them in hot soapy water, rinsing well, and drying them in a low oven at 120°C for fifteen minutes. Everything that touches the oil should be bone dry.

The Gentle Warming Method

The word to hold on to here is gentle. You are coaxing the oils out of the herbs, not cooking them. If the oil ever sizzles, spits or smells fried, the heat is too high and the delicate aromatics are burning off.

• Tip both herbs into your jar and pour over the olive oil, stirring with a dry spoon so no pockets of dry herb remain.
• Set the jar in a bain-marie or a bowl over a pan of barely simmering water. The water should be steaming, not rolling.
• Keep the oil between 40°C and 50°C — comfortably warm to the touch, like a bath for a small child. Never let it climb above 60°C.
• Leave it for two to three hours, stirring every half hour or so and topping up the pan water as needed.
• Test by scent: when the oil smells richly, unmistakably of sage and thyme, it is done.

If you would rather not stand over a pan, a slow cooker on its lowest setting works beautifully, and a yoghurt maker is almost purpose-built for the job. A cold infusion is even simpler: seal the jar and leave it in a cool, dark cupboard for three to four weeks, shaking it daily. It takes longer but captures a slightly greener, fresher note.

Straining and Bottling

Let the jar cool until it is comfortable to handle, then line a fine sieve with a double layer of muslin and set it over a jug. Pour the contents through and let it drain undisturbed for twenty minutes — resist the urge to prod at it.

Once the flow slows to a drip, gather the muslin into a bundle and squeeze firmly. You will be surprised how much good oil is still held in the herb. Some makers prefer to leave that last squeeze out, believing it makes a cloudier oil; both are perfectly good, so squeeze or don't, as you please.

Funnel the oil into your sterilised bottle, leaving a little headspace, and cap it tightly. Label it with the herbs and the date. You should end up with around 450ml from a 500ml start.

Storing and Using Your Oil

Keep the bottle in a cool, dark cupboard — not beside the hob, and not on a sunny windowsill. Made this way, with thoroughly dried herbs, the oil will keep for six to nine months, and often a year. Refrigeration is not necessary; cold oil simply clouds and thickens, though it will clear again at room temperature.

In the kitchen, this is above all a dressing oil. Whisk three parts oil with one part lemon juice or cider vinegar, a teaspoon of Dijon mustard, a pinch of salt and a little sugar, and you have a vinaigrette that lifts a bowl of winter leaves beautifully. It is excellent drizzled over roasted carrots, new potatoes, white beans or sliced tomatoes, stirred through a grain salad, spooned over a bowl of soup, or rubbed into a chicken before it goes in the oven. A little over warm bread with salt is not a bad use of it either.

Small Cautions Worth Knowing

• Use dried herbs only for oil you intend to store in a cupboard. Fresh leaves carry water, and water trapped in oil can allow harmful bacteria to grow.
• Never add fresh garlic, chilli or citrus peel to a cupboard-stored oil for the same reason.
• Keep everything dry — jar, spoon, funnel and fingers. A drop of water is the enemy of a long-keeping oil.
• Discard the oil if it smells waxy, like old crayons or rancid nuts, or if you see cloudiness, sediment or mould. Trust your nose.
• For skin use, patch test on the inner arm first. Sage contains thujone, so concentrated sage preparations are best avoided in pregnancy and by anyone with epilepsy. Keep infused oils away from babies and very young children.

Made carefully and used generously, a bottle of sage and thyme oil is one of the quiet pleasures of a well-kept herb garden — the summer border, captured and poured out over the darker half of the year.