Natural Spider Repellents UK: Conkers, Peppermint & More

First, a Reassurance

Before we dive into repellent methods, let's be clear about one thing: UK house spiders are harmless. The giant house spider (Eratigena atrica) that scuttles across your living room floor in September may look alarming, but it cannot hurt you. Even the false widow spider (Steatoda nobilis), which has received sensationalist press coverage, delivers a bite no worse than a bee sting in the rare event that it bites at all. No spider commonly found in UK homes poses a genuine health risk to healthy adults.

That said, a fear of spiders (arachnophobia) is one of the most common phobias in the UK, and not wanting spiders in your living space is perfectly reasonable. This guide is here to help you reduce spider encounters using natural, non-lethal methods. We will rate every commonly recommended method honestly and tell you which ones have real evidence behind them.

Natural Spider Repellent Methods

Peppermint Oil Spray (Effectiveness: Moderate to Strong)

Peppermint oil is the best-evidenced natural spider repellent. Spiders taste and smell through sensory organs on their legs (called chemoreceptors). When they walk across a surface treated with peppermint oil, the strong menthol creates an intensely unpleasant sensory experience. Several studies have shown that spiders avoid surfaces treated with peppermint oil, making it one of the few natural repellents with genuine scientific support.

How to use it: Mix 15 to 20 drops of pure peppermint essential oil with 250ml of water and a small squirt of washing-up liquid (which helps the oil mix with the water) in a spray bottle. Shake well before each use. Spray along windowsills, door frames, corners of rooms, behind furniture, and around any gaps or cracks where spiders might enter. Reapply every 5 to 7 days.

Limitations: Needs regular reapplication. The scent fades and the repellent effect diminishes. Peppermint oil can irritate cats — use cautiously in homes with feline pets. Cheap, diluted oils are far less effective than pure, high-quality peppermint essential oil.

White Vinegar Spray (Effectiveness: Moderate)

White vinegar is a natural spider repellent thanks to its acetic acid content. The strong, sharp smell is unpleasant to spiders, and the acid irritates their sensory organs on contact. Like peppermint, it works best when applied to surfaces that spiders cross rather than sprayed into the air.

How to use it: Mix equal parts white vinegar and water in a spray bottle. Spray along windowsills, door frames, skirting boards, and corners. Avoid natural stone surfaces (marble, granite) as vinegar can damage them. The vinegar smell dissipates within an hour but leaves a residue that spiders can detect.

Citrus Peel and Lemon Juice (Effectiveness: Moderate)

Spiders dislike the scent of citrus. The d-limonene in lemon, orange, and grapefruit peel acts as a natural repellent. This is a pleasant-smelling alternative to vinegar and works well in kitchens and living areas.

How to use it: Rub fresh lemon or orange peel along windowsills and door frames. Place peels in corners and behind furniture. You can also mix lemon juice with water for a spray solution. Replace peels every 2 to 3 days as they dry out and lose potency.

Cedar Wood (Effectiveness: Moderate)

Cedar contains natural oils that many insects and spiders find repellent. Cedar blocks, chips, and essential oil have been used for centuries to deter moths, and they also have a measurable repellent effect on spiders. The advantage of cedar is that it is long-lasting — a cedar block continues to release its scent for months.

How to use it: Place cedar blocks or chips in wardrobes, on windowsills, and in corners of rooms. Sand the surface of cedar blocks occasionally to refresh the scent. Cedar essential oil can be used in the same way as peppermint oil — mixed with water in a spray bottle.

Eucalyptus Oil (Effectiveness: Low to Moderate)

Eucalyptus oil has mild repellent properties against spiders and other insects. The strong, medicinal scent is thought to overwhelm spider chemoreceptors in a similar way to peppermint, though the evidence is weaker. It can be used as an alternative for people who dislike the smell of peppermint.

How to use it: Mix 10 to 15 drops of eucalyptus essential oil with 250ml of water and spray along spider-prone areas. Alternatively, place a few drops on cotton wool balls near windows and doors.

The Great Conker Debate

No guide to natural spider repellents in the UK would be complete without addressing the great British conker question. Every autumn, millions of people across the country place conkers (horse chestnuts) on windowsills and in corners, convinced that they keep spiders at bay. It is one of the most cherished pieces of British household folklore.

The science: The theory is that conkers contain saponin, a chemical compound that spiders find repellent. In 2010, a group of pupils at Roselyon Primary School in Cornwall won a prize at the Royal Society of Chemistry for their experiment testing this theory. Their conclusion? The conkers had no significant effect on spider behaviour. Several subsequent informal experiments have reached similar conclusions.

Our verdict: There is no robust scientific evidence that conkers repel spiders. The saponin content is likely too low, and spiders have been photographed happily sitting on top of conkers. However — conkers are free, harmless, look quite nice on a windowsill, and collecting them in autumn is a pleasant activity. If placing conkers around your home gives you psychological comfort, there is absolutely no reason not to do it. Just don't rely on them as your only defence if spiders genuinely bother you.

Preventing Spiders Naturally

Beyond repellents, there are practical steps you can take to reduce the number of spiders entering your home. These address the root causes of why spiders come indoors.

Turn Off Outdoor Lights

Outdoor lights attract flying insects — moths, midges, mosquitoes, and gnats. These insects, in turn, attract spiders that feed on them. Webs around exterior lights and lit windows are a direct result of the insect buffet you are inadvertently providing. Turn off unnecessary outdoor lights in the evening, or switch to yellow or sodium vapour bulbs that attract fewer flying insects. This single change can noticeably reduce spider numbers around your windows and doorways.

Regular Cleaning and Vacuuming

Regular cleaning removes webs, egg sacs, and the insects that spiders feed on. Pay particular attention to corners, behind furniture, under beds, and along skirting boards. Vacuuming is surprisingly effective — it physically removes spiders, webs, and egg sacs in one pass. During spider season (September to October), a weekly vacuum of spider-prone areas makes a significant difference.

Seal Gaps Around Windows and Doors

While house spiders typically live indoors year-round, garden spiders and other outdoor species do enter through gaps. Check the seals around windows and doors, particularly older or draughty ones. Fit brush strip draught excluders to the bottom of doors. Seal gaps around window frames with silicone sealant. Besides deterring spiders, this improves your home's energy efficiency.

Remove Vegetation from Walls

Climbing plants such as ivy, wisteria, and Virginia creeper provide a direct highway for spiders from the garden to your window frames. If spiders are a concern, cut back any vegetation touching or overhanging windows and external walls. Trim hedges and shrubs near the house to reduce harbourage.

Reduce Clutter

Spiders thrive in undisturbed, cluttered spaces. Boxes in spare rooms, piles of magazines, cluttered garages, and overstuffed cupboards all provide ideal hiding spots. Decluttering and organising these spaces removes spider habitat and makes regular cleaning easier.

Best Natural Spider Deterrent Products

These are the top-rated natural and humane spider deterrent products available in the UK. We have prioritised genuinely non-toxic repellents and humane catch-and-release tools.

When Natural Methods Aren't Enough

For most people in the UK, natural spider repellents combined with good household practices are more than sufficient. UK house spiders are harmless, and reducing their numbers — rather than eliminating them entirely — is a realistic and sensible goal. Complete elimination is neither necessary nor practically achievable in most homes.

However, if you have a severe spider phobia that affects your daily life, or if you are dealing with an unusually large number of spiders in a specific area (perhaps a basement or outbuilding), chemical spider repellent sprays can provide a stronger barrier. These typically contain synthetic pyrethroids that create a residual barrier lasting several weeks.

Frequently Asked Questions

Do conkers really keep spiders away?

There is very little scientific evidence that conkers (horse chestnuts) repel spiders. This is one of the most persistent pieces of British folklore, but controlled experiments have not demonstrated a significant repellent effect. The theory is that conkers contain saponin, which spiders dislike, but the concentration is likely too low to have a meaningful impact. That said, conkers are free, harmless, and many people enjoy the tradition — there is no downside to placing them on windowsills alongside methods with stronger evidence.

What is the best natural spider repellent?

Peppermint oil spray is the best-evidenced natural spider repellent. Spiders taste and smell through sensory organs on their legs, and the strong menthol in peppermint oil creates an unpleasant surface that they avoid crossing. Mix 15 to 20 drops of pure peppermint essential oil with water in a spray bottle and apply to windowsills, door frames, and corners. Reapply every 5 to 7 days for continued effectiveness.

Are UK house spiders dangerous?

No. The vast majority of UK house spiders are completely harmless to humans. The giant house spider (Eratigena atrica), the most common large spider found in UK homes during autumn, cannot deliver a medically significant bite. The false widow spider (Steatoda nobilis) can bite and cause localised pain similar to a bee sting, but serious reactions are extremely rare and typically only affect people with specific allergies.

Why do spiders come into houses in autumn?

The spiders you see indoors in September and October are almost always male house spiders that have left their webs to search for a mate. They are not coming in from outside — they have been living in your home all year, hidden in wall cavities, behind furniture, and in undisturbed corners. The autumn mating season simply makes them more visible as they wander across open floors and walls. This is why you suddenly see large spiders in autumn when you did not notice them all summer.

Does keeping lights off outside reduce spiders?

Yes, and it is one of the simplest and most effective natural spider prevention measures. Outdoor lights attract flying insects such as moths and midges, which in turn attract spiders that feed on them. Turning off unnecessary exterior lights or switching to yellow or sodium vapour bulbs (which attract fewer insects) can noticeably reduce the number of spiders around windows and doorways, particularly during the warmer months.