How to keep a garden warm: heat, shelter, and what each one costs an hour

Heat is the second thing to fix, not the first. Wind takes more warmth off a person than cold air does — that is why a still 6°C evening is pleasant and a breezy 9°C one is not — so the order that works is: block the wind, put something overhead, then add heat, then stop sitting on cold metal. Do all four and a British garden is usable most of the year. Do only the fourth and you will burn gas to heat the sky.

What follows is each of those four, what it costs to buy, and — the part nobody publishes — what it costs to run per hour.

What each option costs to run, per hour

Every guide to outdoor heating lists the options. None of them tells you what happens to your bill, which is the only question that separates them once you have seen the photographs. Electricity here is charged at the October–December 2026 price cap; gas figures assume a 13kg propane bottle at £40 to £60, which is the part of this that moves most.

The gap is the story. An electric heater costs roughly a tenth of what a gas fire pit table costs to run, and a gas fire pit table is the one people want anyway — because it does something the electric one cannot, which is give a group something to sit around. That is a fair trade as long as it is made deliberately.

First: stop the wind

A 10mph breeze at 8°C feels like about 5°C, and it strips the heat off a patio heater before it reaches anyone. Blocking it is the cheapest degree of warmth available and the only one that costs nothing to run.

A solid barrier is the wrong instinct. Wind hitting a solid fence rolls over the top and drops back down as turbulence a couple of metres behind it, so the sheltered patch is short and gusty. A screen that lets roughly half the wind through slows it instead of stopping it, and shelters a distance of up to ten times its own height downwind. Our freestanding metal screens are cut-out panels for exactly that reason — at 198cm tall, a pair placed on the windward side of a seating area does more for comfort than another kilowatt of heat. The rhombus pattern and the twisted-line pattern are the same panel in different cuts, and the triangle screen is the most open of them.

Second: something overhead

Heat rises and leaves. A roof of any kind — canopy, pergola, gazebo — keeps some of it at head height instead, and keeps the drizzle off, which in Britain is the thing that ends an evening more often than the cold does. It is the difference between a heater warming people and a heater warming the sky.

A lean-to pergola against the house is the cheapest way to get a roof because the wall does half the work, and it puts the sheltered area right by the back door where it actually gets used. Freestanding, a retractable-canopy pergola or a pergola with curtains gives you a roof you can open in July, and the curtains do the wind job and the roof job together. A 3m double-roof gazebo is the version that comes down for winter.

One rule that is not negotiable: nothing with an open flame goes under a fabric canopy. A gas fire pit table belongs on the open side of a pergola, not under the middle of it, and the clearances are in our gas fire pit guide.

Third: fire pit tables — heat you sit around

A gas fire pit table is the only form of outdoor heating that arranges people rather than just warming them. A tall patio heater puts out similar heat and everybody stands under it looking at nothing; a fire pit table puts the flame in the middle of a low table and the seating faces inward, which is why they sell and why they keep selling.

Two outputs, and the honest difference between them is smaller than the numbers suggest. 40,000 BTU — from £149 — is enough for a patio with walls or fencing close by, and a bottle lasts noticeably longer. 50,000 BTU (£179 with a glass screen and cover) earns its extra where the space is open, where more than four people sit round it, or where it is being used in December rather than September.

The glass screen matters more than the extra 10,000 BTU. It stops the wind pulling the flame sideways, which is what makes a fire pit table feel weak on exactly the evenings you bought it for, and it keeps the heat rising where people are rather than across the garden. If the budget stretches to one upgrade, take the screen over the burner. The 81cm table at £187 and the grey 81cm at £198 are the larger tops, which matter if the table also has to hold drinks for six.

Every one of ours hides the bottle inside the base, takes a standard 13kg patio gas bottle, and comes with lava rock. Which fuel suits you at all — gas, wood or electric — is its own question, and we have a guide to that.

Freestanding gas heaters — heat you stand under

The 180cm mushroom heater is the pub-garden option, and it is the right one where people are standing and moving: a bar, a barbecue, the end of a party. Ours run at 11kW with adjustable output, which is roughly a 3m circle of useful warmth and about 16 hours from a bottle at full. Turned down, which is how they are actually used, considerably longer.

Buy one with a tip-over cut-off and use it — this one has it. A tall heater with a gas bottle in its base is exactly the shape that goes over in a gust, and the cut-off is the part that makes that an inconvenience rather than an incident. Weight the base, and bring it in or cover it when it is not in use.

Electric — the cheap one, with a catch

At 53p an hour, electric heating costs a fraction of gas, and if there is a socket and a roof it is the sensible answer. The catch is both of those conditions. Electric patio heaters want mounting — to a ceiling, a wall, a beam, or a parasol pole — and they want to stay dry, so they suit a covered porch, a veranda or a pergola with a solid roof far better than an open lawn.

Choose infrared over convection outdoors. Convection heats the air, and outdoors the air leaves; infrared heats the surfaces it lands on, including people, and works in a light breeze. The 1000–2500W infrared hanging heater is the one to want, the 1000–2000W waterproof ceiling heater is the cheaper mount-and-forget version, and the parasol-mounted heater clamps to a 25–70mm pole and needs no fixings at all — the only one of the three a tenant can install.

Wood, if you want the smell

Nothing gas does smells like a wood fire, and for some people that is the entire point. A smokeless wood fire pit at £120 is the cheapest heat here to buy and among the dearest to run once you are buying kiln-dried logs. Double-wall smokeless designs burn the smoke rather than releasing it, which is what makes them tolerable in a garden with neighbours either side.

Burn dry seasoned or kiln-dried wood and nothing else — wet wood is most of what makes a fire pit a nuisance, and treated timber and household waste are both illegal to burn. If you are in a smoke control area, check your council's position before buying anything wood-burning; gas has no such restriction, which is one of the quieter reasons it has taken over.

The half that is not heating

Cold reaches people through what they sit on before it reaches them through the air. A metal chair at 5°C takes heat out of you faster than 5°C air does, so cushions, a throw over the back of each seat, and something on the ground are worth more than they sound — and cost nothing to run. Our garden furniture sets are specified with cushions for that reason rather than for looks.

Light does the rest. A garden that is warm and dark still empties at six o'clock in November, because people leave when it feels like night rather than when it feels cold. Low, warm light at the edges — a pair of dimmable solar bollards along a path, a rattan solar floor lamp beside the seating — extends the evening further than another kilowatt would. Warm white, not cool: the difference is in our lighting guide.

If you meant keeping the plants warm

Different question, and worth saying plainly rather than pretending it is the same one. Plants come through a British winter on drainage and root protection, not on heat: pots up off the ground so they drain and do not sit in ice, the vulnerable ones grouped against a wall, and containers in a material that does not split when the water in it freezes. Which materials actually survive is a guide of its own, and what furniture can stay out is the matching question for everything else in the garden.

The short version

Block the wind with something half-open before you buy any heat at all. Get a roof over the seating if you can, and keep open flame out from under fabric. Then choose: electric if there is a socket and a cover, at around 53p an hour; a gas fire pit table if you want people to gather rather than merely be warm, at £2 to £4 an hour and a bottle every dozen evenings; a tall gas heater if people will be standing. Take the glass screen over the bigger burner. Then put cushions on the chairs and a light at the edge of the garden, because the last two degrees are not a heating problem.