If you mow often during the summer, it’s tempting to be like my dad and just park the mower outside and call it good. But doing that for weeks on end can lead to long-term damage you might not notice right away. Heat, rain, and direct sunlight don’t mix well with metal, rubber, plastic, or gas.
“Depending on where you live, storing a lawn mower outside during the summer risks exposing it to rain and harsh UV rays which can cause significant damage,” shared Wes Bollingmo, channel and product support manager at Toro. The impact can sneak up on you—until one day it just won’t start.
Weather Isn’t Just a Cosmetic Problem For Lawn Mowers
Sunlight and moisture are the two biggest threats to your mower’s health.
If left outside, rain can seep into the engine, pool around the mower deck, and stick in hard-to-dry spots causing water damage. If you've ever had to fight with a spark plug that's rusted into a push mower engine, you know the damage outdoors can do.
“Rain can lead to rust and corrosion, while UV exposure can crack and fade plastic parts,” highlights Bollingmo. Over time, this damage adds up. “Storing outside all summer could shorten the mower’s lifespan. Toro recommends storing it in a cool, dry place to prevent issues no matter the season.”
Extreme temperatures also accelerate fuel breakdown in gas mowers. Rubber fuel lines can crack, and batteries don’t do well in hot, direct sun either. If the mower sits on grass or dirt, moisture can get trapped underneath, creating even more rust risk from below.
When You Might Get Away With Keeping Your Mower Outside
If you live in a dry area where rain is rare and humidity is low, storing the mower outdoors with a mower cover might work—for a while. But even then, you’ll want to make a few upgrades.
Covers that trap moisture can do more harm than good, and setting the mower directly on soil can pull water up into the deck.
Ask yourself:
- Is it exposed to daily sun or rain?
- Am I using a breathable, UV-resistant cover?
- Is the mower sitting on a hard, dry surface?
- Am I storing it under a roof or fully out in the open?
A few weeks out in the yard may be fine; a whole summer usually isn’t. Damage tends to show up after the fact, when expensive equipment parts start to crack, rust, or stop working.
Better Options For Outdoor Storage
You don’t need a giant garage or a full shed to protect your mower. There are simple setups that can keep it dry and shaded all summer long:
- Plastic sheds or resin sheds
- Lockable deck box (for small electric mowers)
- UV-resistant, waterproof cover (that’s also breathable or has air vents)
- Concrete pavers or gravel as a base
- Covered patio or awning spot with good airflow
- Folding mower wall racks (for vertical storage)
These options take up less space and still help avoid the worst weather-related damage. They also keep pests out—especially rodents, which are known to chew wires and nest inside engines.
FAQ
Is it okay to leave fuel in my mower's gas tank over the summer?
If you're using it regularly during the mowing season, yes. But if it will sit for a few weeks or more, old gas can gum up the carburetor and fuel tank. To be safe, add fuel stabilizer or run it dry if you expect a long break between uses.
How do I keep my mower blade from rusting in summer?
Clean it often and store the mower somewhere dry. If the lawn mower blades or mower deck gets caked with wet grass, rust can start fast. Scraping off clippings with a putty knife and occasionally spraying the underside with light oil or WD-40® EZ-REACH® (with a flexible straw) can help it last longer.
