Keep Your Lawn Mowed with the HART 21" Self-Propelled Lawn Mower
What a difference a year makes! Looking back at HART's 40V cordless lawn mower, there's plenty of room to move up to a higher level of performance. As we head into spring mowing season, the HART 21-Inch Self-Propelled Lawn Mower promises to reach even greater heights. We put it to the test to see if it's right for your lawn.
advantage
- excellent cut quality
- Handles fold down for easy vertical storage
- Bags, covers or side discharges
- Single point height adjustment
- Power boost mode gives you short power jumps in lush grass
shortcoming
- We wanted to embed the presence bar into the handle for a more comfortable grip
- Drive speed slider prone to mis-hitting
cutting force
HART's brushless motor spins a 21" blade with some nice muscle behind the blade. It cut through our thick St. Augustine grass with more confidence than some HART mowers we've tested before.
One cool feature is the temporary power boost. The motor automatically adjusts power as we expect. You can also actively activate it by pressing the blade activation button again as you approach a tough patch. It enters a high power state for about 6 seconds.

There's a power gap to the best performing battery-operated lawn mowers, but they're also hundreds of dollars more. In terms of changing gas, this mower works better than the 140cc class.
cutting quality
HART gives you three discharge options and includes everything your lawn mower needs. Using a true side discharge instead of a rear attachment, the mower easily distributes cuttings several feet outside our mowing path.
If you like coverage as much as we do, the plugs are simple to install. Simply lift the rear hatch and install the plug to close the bagger chute. The mulch was satisfactory compared to what we've seen from HARTs in the past, and more like what we've come to expect from mid-to-high-end mowers.

The high airflow that contributes to its mulching characteristics also lends itself to impressive bagging for a battery-operated mower.
Cutting uniformity
Looking back at the grass we cut, we are very pleased with the results. Aside from some messy blades, we saw a big improvement in the uniformity of the overall cut.
run
The HART 21" self-propelled lawn mower has two active battery bays. However, it does not have an automatic switching function. When one battery dies, you need to flip the red key under the cover to restart the mower and keep driving the truck. If you have a smaller lawn, you can run the mower on just one battery.

HART estimates that up to 3/4 of an acre can be cut on a single charge under optimal conditions. We tested run times with moderate maintenance cuts in dry weather with temperatures hovering around 90° F (run times tend to drop off slightly at higher temperatures). Using the two 6.0Ah batteries in the kit, we cut a total of 50:57. Hart's estimate might be a bit ambitious, but 1/2 acre is certainly possible.
HART 21" Self-Propelled Lawn Mower Design Notes

- 21" Polymax composite deck is lightweight, corrosion resistant and strong enough to take moderate impact from yard debris
- If space is limited, the Fast-Fold handle allows you to easily store the mower upright
- Quickly adjust deck height from 1" to 4" with a single point adjustment
- LEDs on the front for mowing in low light
- Slide thumb switch lets you easily adjust drive speed to match your preferred walking pace
HART 21" Self Propelled Lawn Mower Prices
Get this HART mower for $498 at Walmart. It comes with two 6.0Ah batteries and a fast charger that charges each in under an hour. It comes with a 5-year limited tool warranty and a 3-year limited battery warranty.
the bottom line
After using the HART 21" self-propelled lawn mower, we have been impressed with the improvements in performance, cutting and design over last year's model. The design team at HART set its sights high and stepped up to compete with other mowers in the $500 range.
To view the complete HART 40V range, click here.
HART 21" Self-Propelled Lawn Mower Specifications
- Model: HART HLPM061US
- Power supply: HART 40V battery
- Cutting Tape: 21"
- Accessories: Mulch Plugs, Side Discharge Chutes, Collection Bags
- Motor: Brushless
- self-propelled
- Cutting height: 1-4 inches
- Deck height adjustment: 7-position single point
- Warranty: 5 years on tool, 3 years on battery
- Price: $498 (kit)