How to Winterize Your Robot Mower (and Why the Battery Is the Whole Game)

The number one avoidable robot mower repair in spring is a dead battery. It happens when a mower sits through winter with a drained or frozen battery, and it's the repair that a single afternoon of prep in November would have prevented.

Here's the part most winterizing guides get wrong: Segway and Husqvarna don't give the same instructions. The battery step is different for each brand, and doing the wrong one is how batteries get killed. Here's what each manufacturer actually says, from their own winter storage guides.

Segway Navimow: charge to 85%, then hibernate

Segway's X4 winter storage guide is specific. Charge the mower to at least 85% battery, then put it in hibernation from the app — tap "Begin hibernating" to power it off. Hibernation uses less energy than a standard shutdown, which is what preserves the battery over months of storage. To wake it in spring, charge it before you power it on.

Before you hibernate, disable all mowing schedules in the app so the mower can't set off on its own while you're working on it.

Then mark the charging station's spot. Segway ships four silicone pegs in the mower's box for exactly this — unplug the station, unscrew it, and leave the pegs in the ground where it sat, so you put it back in the same place in spring. If you move the antenna, you'll need a new map, so note where that is too.

Take the blades off — gloves on, they're sharp — and clean the mower thoroughly. Brush it down, hose off the dirt, and let it dry completely. Pack the mower, the charging station, the antenna, and all the cables into the box, and store it indoors somewhere dry and frost-proof, between 5°C and 45°C (41°F to 113°F).

If you don't hibernate it, Segway says to recharge the battery once every three months through winter.

Husqvarna Automower: charge it fully, then switch it off

Husqvarna's instruction is different, and it's blunt. Charge the battery fully before winter storage. Their manuals carry a caution in bold: if the battery is not fully charged, it can be damaged and in certain cases rendered useless. When it's fully charged, set the main switch to OFF.

Clean the mower carefully before you put it away, and check the blades and wheel bearings for wear while you're in there. Store it standing on all four wheels in a dry, frost-free place, preferably in its original packaging. Husqvarna also sells a wall hanger if you'd rather hang it.

The charging station and power supply come indoors. The boundary wire and guide wire can stay in the ground — just put the wire ends in a container with grease so they don't corrode. If the charging station has to stay outside, Husqvarna says it must stay connected to the mains and the wires all winter. Don't leave it out unplugged.

Husqvarna also recommends fully charging the battery at some point during the winter to extend its life. And their manuals say to take the mower to a dealer for a service before winter storage. That's not a sales line — it's how they tell you to keep the machine in good condition.

When to do it

Winterize when your grass stops actively growing — typically when soil temperatures drop below 50°F for several days and overnight temperatures start settling toward freezing. In most of the US that's late October or November. Don't wait for the first snowfall.

For the final cut of the season, leave the grass a touch longer than your summer setting, around 2.5 to 3 inches.

Either way, the thing to do is the prep, not the repair. An hour in November is the difference between a mower that wakes up in spring and one that doesn't.

Sources: Segway Navimow X4 Winter Storage Guide (navimow-support.zendesk.com); Husqvarna Automower operator's manuals (winter storage sections).