Overwintering Garden Furniture: What Can Stay Outside – and What Can't

"Does garden furniture have to go indoors for winter?" The honest answer: it doesn't depend on the calendar, but on the material. Teak, aluminium, stainless steel and high-quality synthetic-fibre weave survive the winter outdoors; cushions, pillows and textiles, on the other hand, belong indoors, dry, without exception. The real opponent here isn't the cold itself but water – standing water that freezes, and moisture that condenses under tight covers. Frost days are part of every Zurich winter, and you can plan around exactly that: if you know your material, you can make an informed judgement instead of clearing everything away. The following sections go through the major material groups one by one.

Untreated teak survives the winter outdoors – and it's allowed to turn grey while doing so. The honey-brown colour gradually shifts outdoors into a silver-grey patina, because the pigments in the top layer of the wood fade. According to a leading teak furniture manufacturer, that's purely a colour change: the greying doesn't harm the wood, and treatment with care products or sealants has no effect whatsoever on the strength or lifespan of the furniture. If you want to keep the honey colour, you're deciding on looks, not substance. Teak is naturally oily by nature – which explains its composure in the face of the weather. In practice, manufacturers recommend it's enough to let the furniture weather naturally and clean it once or twice a year; soapy water with a non-abrasive sponge is standard in the trade for that. Important for winter: place the furniture under cover or at least tilt it so water can drain away. And if you want to store it, choose the watertight garden shed or the garage – explicitly not the heated living space: the abrupt swings in temperature and humidity can, according to the manufacturer, cause the wood to crack. The unheated garage is the better winter spot than the warm living room.

Aluminium garden furniture is weather-resistant and can stay outside year-round – that's the materials knowledge of the garden furniture trade. The reason is established materials science: the top layer reacts with oxygen and humidity to form aluminium oxide and so protects the layers beneath; a powder coating adds further protection. Water alone is enough for cleaning – abrasive sponges and aggressive cleaners stay in the cupboard. Stainless-steel and polyrattan furniture also survive overwintering outdoors; a protective cover is still recommended in furnishing practice, though. Steel is different: steel garden furniture needs more care and should be treated before winter to prevent rust. If you're not sure whether your frame is aluminium or steel, it's best to find out before the first frost – the answer decides the winter programme.

Cushions and pillows are the one category with no exceptions: they belong fully dry and ventilated indoors. According to manufacturer information from the premium-weave segment, furniture and cushions must be thoroughly dry before longer covering or storage; covers that have got wet must never be packed together or stored folded, but must dry first in a well-ventilated place – otherwise mould stains threaten. The same mechanism turns closed cushion boxes into a trap: in the cold months, condensation can form inside, showing up on the cushions as mould stains. A proven practical tip from the specialist trade: put a container of rice or cat litter in the box – it absorbs the moisture. The same logic applies to protective covers: don't pull them all the way to the ground, so air can circulate. A cover should keep rain out, not trap moisture in.

It isn't the cold that damages garden furniture, but water that can't drain away. The physical reason comes from the US Geological Survey (USGS): when water freezes, its density drops by around 9 percent – ice, in other words, needs around 9 percent more volume than liquid water. Wherever water sits in hollows, vessels or absorbent materials and freezes, it presses against its surroundings. There's plenty of opportunity for that: the City of Zurich defines a frost day as a day on which the minimum temperature falls below 0 °C; on an ice day, even the maximum temperature stays below zero. Days like that are part of every Zurich winter. The most important precautions follow directly from this:

If you know you have neither a cellar nor a garage available, choose materials from the start that are allowed to stay outside – and plan storage space only for the cushions. We clarify exactly these questions in the consultation, before a quote is drawn up. In our showroom at Nüschelerstrasse 30 in Zurich, five minutes' walk from the main station, we show outdoor furniture from Unopiù and outdoor kitchens from azado of Wittenbach, SG – and talk openly about which piece needs which winter spot. The initial consultation is free; we're open Monday to Friday from 10:00–19:00, Saturday from 10:00–18:00. Delivery and assembly are handled throughout Switzerland by our own team — items in stock usually within 48 hours, made-to-order items according to the manufacturer's schedule.