Spiders can be found in almost every room in your home. Backyard sheds are no exception.
Spiders get everywhere. It makes no difference if you have a wood, plastic, or metal shed. Spiders will take up house if they sense a food source exists there, and they can get in.
There are two ways to go about keeping spiders out of your shed:
Spider-Proof Your Shed
There is an old saying - 'prevention is better than a cure - and when you minimize how spiders can enter your shed, and you take away potential hiding places for them and other insects that become their food, you are halfway to spider-proofing your shed.

Outside the Shed
You first need to tackle the outside of the shed:
Inside the Shed
Existing Spider Problem
Suppose you have an existing spider infestation or want to prevent one completely. In that case, I recommend emptying your shed, as in our article 'How to Spring-Clean, De-Clutter, and Makeover Your Shed.'
If you've ever disturbed a spider egg sac and seen hundreds of the little blighters running for cover in all directions, you'll appreciate how they can get everywhere and hide anywhere. An empty shed makes it a lot easier to sort your spider problem.
You will need to deep clean the interior when the shed is empty.
Before you refill the shed, wipe over shelving and storage containers and check for live insects, larvae, or droppings in storage containers, boxes, and bags.

Spider Prevention - Fumigation
An alternative to emptying the shed is to fumigate it with a 'spider bomb.' This will release a fine penetrating fog of insecticide chemicals that will permeate the whole shed, including any cracks or recesses, and dispose of any spiders or bugs hiding there.
Spider Preventive Routines
After gardening, you should clean and dry the tools before putting them back in the shed and keep the shed door shut when you are working in the yard.
Make your Shed Interior Less Attractive to Spiders
To keep spiders away from your shed, you need to follow some simple ongoing procedures:
Remove Food Sources
Spiders generally set up homes in sheds that can provide them with a food supply, so you must remove all potential food sources straightaway. As with other insects, they like places to hide, nest, and lay eggs, so you need to reduce the potential for them to do that too.
Don't keep garden refuse in the shed - no grass cuttings, deadheading, pruning debris, leaves, and twigs - anything that could contain insects that will attract spiders or attract other species. Leave your garden rubbish in the yard, sacked up for disposal, or on the compost heap.
Similarly, if you are going to keep soil or potting composts in the shed, they should be kept in airtight containers. Insects love these materials to nest and leave eggs in, attracting spiders. Better still, keep your supplies away from the shed.
None of this will be straightforward if you keep small pets in a shed, even if you provide them only with winter quarters. Pets such as rabbits, ferrets, guinea pigs, etc., will need bedding materials such as hay or straw, which will be attractive to insects for nesting or laying eggs.
Keeping pets in a shed means keeping the shed tidy regularly and following the other recommendations. Namely - keep animal feed in airtight containers, ensure bedding materials are sacked and sealed, dispose of soiled material daily, and keep everything clean.
As an added precaution, you should also store your trash cans away from the shed because they'll only attract more bugs as well.

Lavender oil makes an excellent spider repellent.
Add Spider Deterrents
An extra layer of defense in your quest against spiders would be introducing some spider repellents. Spiders do not like strong smells. They can't stand them. They naturally repel spiders, so if you can deploy some of these inside and outside the shed, it all helps.
What is the Best Spider Repellent?
Outside the shed grow some spider repelling plants in containers, not the ground. Not only will these plants keep the multi-legged little nuisances away from windows and doors, but they also produce a nice aroma that is pleasing to us while not to them.
Great spider repellent plants to consider are:
Inside the shed, you can use the oils from some of these spider-repellent plants to great effect as a spray. Mix the oil with some water and a little dish soap to help break down the oil, so it mixes with the water, then spray it around all access points to the shed - vents, windows, and doors.
You can leave a ball of cotton wool with a few drops of oil on it in many nooks and crannies you have seen spiders lurking. Do this every week. It only takes a few minutes.
Natural Plant Oils that Repel Spiders include:
Recap
You will never create a shed environment that is 100% spider-free, and it is not realistically possible. Spiders are tiny creatures in the main and can sneak in via the smallest gaps.
But you can create an unattractive environment that discourages them from hanging around.
Checklist
