The first properly cold morning always catches a garden bench off guard. One weekend you are eating lunch outside; the next there is a slick of dew across the seat and wet leaves wedged between the slats. Autumn is short, and the couple of hours you spend on maintenance now decides whether your seating comes out in March looking cared for or looking like a job.

None of the work below is complicated. It is mostly about cleaning properly, drying thoroughly and not trapping moisture against the surface.

Clean it properly, not just quickly

You cannot protect a dirty bench. Dust, pollen and bird mess hold water against the surface, and mould spores settle into the film they leave behind. A quick wipe with a damp cloth rarely reaches the places that matter: the joints, the screw heads, the underside of the seat slats and the feet.

Use warm water with a small amount of mild washing-up liquid and a soft nylon brush. Work along the grain on timber and in small circles on metal. An old toothbrush is genuinely useful where an arm meets a backrest. Rinse with clean water from a watering can or hose rather than letting dirty runoff dry back onto the wood.

Two things to avoid. Skip the pressure washer — it drives water into joints, lifts timber grain and can strip powder coating. And keep abrasives away from painted metal, because a scrubbed patch becomes a rust patch by January.

Dry it completely — the step most people rush

This is where autumn maintenance succeeds or fails. Timber that goes into winter damp will swell, split and grow mould from the inside out. Covering a wet bench is worse than leaving it uncovered, because you have effectively built it a small humid tent.

Leave the bench out in sun and breeze for at least a full day after washing. If the forecast is unreliable, tilt it on its side so water can run out of the frame, then check underneath. Pay particular attention to bolt holes, tubular legs and anywhere the frame sits directly on the patio. Stand the feet on small blocks if you can; a centimetre of airflow underneath makes a real difference.

Treat timber while the weather is still dry

Once the wood is clean and bone dry, it is ready for protection. Choose according to the timber and to the look you want. Teak, acacia, eucalyptus and iroko can be left untreated to weather to a soft silver-grey, but a coat of dedicated hardwood oil slows that down and helps repel water. Softwoods and painted benches want an exterior stain or wood paint instead.

Apply thin coats with a lint-free cloth or brush, work with the grain, and wipe off the excess rather than leaving it to pool. One careful coat beats three thick ones. Pick a dry day with a few rain-free hours ahead and read the tin for temperature limits — most exterior finishes want double figures to cure properly. Avoid silicone-heavy sprays, which make future refinishing difficult.

Check the structure while the wood is bare

• Tighten every bolt, screw and dowel, and replace any that are corroded.
• Sand out small splinters and rough patches before treating them.
• Look for hairline splits at the ends of slats and where legs meet the frame.
• Check feet and glides for wear — a worn foot becomes a rotten leg.
• Note anything that creaks when you sit down; a wobble is easier to fix now than in February.

Metal, rattan and composite need less, but not nothing

Cast aluminium and powder-coated steel frames cope well with British winters. Wash them, dry them, then touch in any chips or scratches with matching enamel, because small bare patches spread quickly in damp air. Wrought iron and untreated steel need more attention: wire-brush any rust back to sound metal, apply a rust converter or primer, then paint.

Synthetic rattan and mesh fabrics should be cleaned with soapy water and a soft brush, then rinsed and dried. Never jet-wash woven finishes — water gets inside the weave and stays there. Composite and recycled-plastic benches are the most forgiving: soapy water, a stiff-ish brush for textured surfaces and a rinse is usually enough. Skip abrasive creams that dull the finish.

Cover it, or store it — but let it breathe

A plastic tarpaulin is the classic mistake. It traps condensation underneath, so the bench sits in its own damp microclimate for five months. If you are covering, use a breathable, waterproof cover sized for the bench, with vents or a raised seam, and tie it down so wind cannot flap it loose. Slightly oversized is better than slightly too small.

If you have shed or garage space, storing is the better option. Bring in cushions, throws and parasol canopies — they suffer most and are the easiest to save. Wash cushion covers according to their care labels, dry them fully in the sun, and store them flat or loosely folded somewhere dry rather than compressed in a damp corner.

Stop mould before it starts

Mould needs three things: moisture, still air and something to feed on. Remove any one of those and you have largely solved the problem. So keep surfaces clean, keep covers breathable, and leave a gap for air to move around the legs and seat.

Check the bench every few weeks through winter, especially after storms. Look for black speckling along slats, a green film on fabric, powdery patches on the underside of a seat or table, and dark streaks where water has been sitting. A musty smell is the earliest warning sign and the easiest to act on.

If mould does appear, deal with it outdoors rather than in a closed shed. Wear gloves, and a mask if you are sensitive to spores. For hard surfaces a dedicated mould cleaner or a diluted bleach solution works — but test on a hidden area first, follow the product instructions, never mix cleaning chemicals, and rinse thoroughly afterwards. Fabric needs gentler treatment, so check the care label before washing. If damp and mould are affecting your home rather than the garden, ask a qualified professional for advice.

A dry weekend now, an easier spring

Autumn care is unglamorous work: a bucket, a brush, an afternoon of drying time and a tin of oil. Do it once, properly, and the payoff is a bench that comes through winter without a green tinge, a wobble or a swollen joint. If the weather turns before you finish, prioritise cleaning and drying over treating. A clean, dry bench left uncovered will survive the cold far better than a dirty one wrapped in plastic.

Photo: Kris Møklebust / Pexels