I live in Ontario Canada and experience all four seasons.  Therefore in the winter, I do not tend to use the shed quite as much as I would in the spring, summer and fall.  It is during this time that mice start looking for a warmer place to set up home and start producing even more mice.

You can get all the poisons and traps you want, but if you don’t start with a clean and

organized shed, you will be wasting your hard earned money.  You need to cut off all the food supply, so that they don’t consider your garden shed a free buffet and party house.

It is amazing, what they will eat and what they will turn into a home.  You may look at that cute little mouse and wonder just how much damage can he do?  Numbers, they work quite well in numbers, they actually work like a well oiled machine when it comes to destructive tendencies.  You need to get your line of defense in order before the winter. 

1. Check Everything Before Storing for the Season

You would be amazed at how these critters end up in there in the first place.  You could have a garden shed built like Fort Knox, and yet you can still find them in there.  One of the easiest ways for them to get in is by hiding in the things you plan to store.  At the end of the summer season a few years ago, I had a mouse crawl up under the patio table umbrella now that it was not expanded, and I simply went and placed it in the shed for the winter. 

I just happened to open it a bit to check that there were no moths, and out falls this mouse and off he goes running.  Luckily he ran outside.  They also love to burrow and hang out in those planters, garden furniture, grass bags from the lawnmower and also under the lawnmower and some pond supplies. 

You could be bringing them in, so you need to open the umbrella and get rid of moths and bugs and check for mice, and really check those planters if you have to bring them in.  My mother ended up with a mouse in her house when she brought in a house plant that she had put outside over the summer.  It was sitting proud as can be in the soil, and she didn’t notice it until it was too late.  She had cleaned the plant with a soap and water spray for bugs, but forgot that mice can get a one way free trip into the house this way.  It took weeks to catch it.

Check everything, including the lawnmower and underneath and get rid of old built up grass.  This is your first line of defense.

2. Metal Containers

I have used plastic in the past and the little monkeys have been able to chew through that, even the thickest plastic, so I feel it is time to invest in some metal containers with well fitting lids for any type of seed you need to store in the shed or even in the house.

All that great bird seed we purchase or that grass seed or even leftover veggie seeds especially the corn, or flower seeds are game to these little critters.  It is actually amazing just how much trouble they will go to, to get at those seeds and bulbs.

So, if you need to store bird seed in your garden shed, or garage or house, then make sure when you purchase the bag it comes in, that you quickly transfer it to the metal container, and place the lid on tight.  Don’t leave it in the bag or they will be attracted to it.  Clean up any spills as well.

So now that you have cut off their food supply, let’s make it more difficult to set up house.

3. Don't Leave Anything That Can Become Bedding

This includes newspapers, or any paper bag, grass clippings, patio cushion covers, or any padding.  If you use newspaper in the garden, then maybe it is time to recycle the end of season supply, and start again in the spring.  If you store garden bulbs in paper bags, get them either into the garden or tins.  Just look around your shed.  Give it a good sweeping to get rid of dust and debris and old grass clippings, because they will simply gather this up and call it home.

My sister-in-law had mice turn the owner’s manual in her truck into a chewed up fluffy mess in her glove box.  These critters are geniuses at building a home.  So your best proactive step is to cut off the food supply and the bedding materials.

4. Fill Any Gaps and Holes

My shed is an old wooden shed, and I think there are more holes than shed, but if possible take some caulking to holes around the window or base of the walls to make it harder to get in.  They don’t need a large hole; if you can see to the outside then it is big enough for them.  I my case I have to make it less inviting.

5. Make it Uncomfortable

This one works well for me.  There are many home remedies over the years that work quite well.  Many swear by one more than another, but they do work if they are used in combination with the above steps.  Cut off food supply, get rid of bedding materials, make entry difficult and now make it a nasty environment with products such as peppermint oil, or dryer sheets or moth balls or cat litter.

6. Peppermint Oil

Get a good quality concentrated oil and then using cotton balls, put some liquid on the cotton and place many at different areas of the shed, especially in the corners and along the floor where they will come in, but it wouldn’t hurt to put a few on the shelves.

7. Unused Dryer Sheets

You need to invest in a box of scented dryer sheets and use them fresh from the box and put sheets around the floor and corners and on shelves.  You could use them as well as the peppermint oil.

8. Moth Balls

These will work too, but are not healthy to touch and not everyone can tolerate the smell, but they also keep moths away as well as put off mice.

9. Used Kitty Litter

This is my all time favourite.  I know this sounds gross, but I realized one night when I was

putting the garbage out the night before that also contained a thin bag of used kitty litter that my garbage never would bet ripped open by any critters in the night like my neighbours.

It may not smell very nice, but this works well especially if you will not use the shed very often and want to protect seeds and other supplies.  Place a small open baggy of kitty litter in each corner of the shed, or tie a bag and poke a few holes in it.  Mice will run in the other direction.  This is something many car owners use when storing vintage or project cars to keep them out.  It works in the shed too.  In the spring, just air it out and remove.

10. Commercial Yet Natural Products Online

If you don’t want to go to that trouble, you can get products on the market that are natural and less offensive to you but mice hate, so these are options too.  So, get proactive, and cut off food, housing and quality of life for them and they will move on.