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Best Robot Mower for St. Augustine Grass (2026)

MA MowAutonomous Editorial Team · Updated 2026-06-23 · 8 min read

St. Augustine grass is a popular warm-season grass in the Southern US. It's thick, dense, and requires a higher cutting height than most cool-season grasses. This guide covers the best robot mowers for St. Augustine lawns.

What St. Augustine Grass Needs

St. Augustine grass wants: (1) Cutting height of 2.5-4 inches (higher than most cool-season grasses). (2) Weekly mowing during growing season (May-September). (3) Sharp blades — St. Augustine is thick and tears easily with dull blades. (4) AWD if your lawn has slopes — St. Augustine lawns are common in Florida and Texas, which often have sandy soil.

Our Top Picks for St. Augustine Lawns

For St. Augustine lawns, our top picks: (1) Mammotion LUBA 2 AWD 3000X ($2,499) — AWD for sandy soil, 15.7-inch deck handles thick grass, 1.0-2.7 inch cutting height (set to 2.5+ for St. Augustine). (2) Segway Navimow X450 ($3,499) — 1.6-3.6 inch cutting height (perfect for St. Augustine), 16-inch deck. (3) Dreame A3 AWD Pro ($2,499) — AWD, 1.2-3.0 inch cutting height, LiDAR for tree cover.

Setting the Cutting Height for St. Augustine

St. Augustine wants 2.5-4 inches. Set your mower to 2.5 inches in spring (after last frost), 3 inches in summer (heat stress), and 2.5 inches in fall (before dormancy). Never cut more than 1/3 of the grass blade height at once.

Frequently Asked Questions

Can a robot mower handle St. Augustine grass?
Yes, but you need the right mower. St. Augustine is thick and dense, so you want a mower with a powerful motor and a wide cutting deck (15+ inches). You also need to set the cutting height to 2.5-4 inches. Our top picks: Mammotion LUBA 2 AWD 3000X, Segway Navimow X450, Dreame A3 AWD Pro.
What cutting height should I use for St. Augustine grass?
2.5-4 inches. Set to 2.5 inches in spring, 3 inches in summer (heat stress), and 2.5 inches in fall. Never cut more than 1/3 of the grass blade height at once. St. Augustine cut too short is vulnerable to weeds and drought.
Will St. Augustine grass clog a robot mower?
It can, especially when wet or freshly fertilized. St. Augustine is thick and the clippings can build up under the deck. Clean the cutting deck weekly during growing season. Replace blades every 4-6 weeks — St. Augustine dulls blades faster than cool-season grasses.

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