Here is the full list of all 55 Rusty's Retirement achievements. It takes around 120-150 hours to unlock all of the achievements on Windows.
Unlock all crops
Unlock all berries
Build on every available tile
Place 10 Bulb Hives on a single farm
Build 10 Biofuel Converters on a single farm
Max upgrade a Fertilizer Bot
Unlock the Flower Swamp farm
Earn 1 MILLION spare parts across all farms
Place 100 decorations on a single farm
Play the game for 24 hour (across all farms)
Grow a Giant Cucumber
Max upgrade a Harvest Bot
Max upgrade a Waste Bot
Max upgrade a Feeder Bot
Max upgrade a Berry Bot
Produce 100,000 biofuel across all farms
Collect 1,000 animal waste
Unlock 25 crops
Earn 250,000 spare parts across all farms
Build Splunk's House
Grow a Giant Pumpkin
Deploy one of each robot on a single farm
Place 25 decorations on a single farm
Build Slate's Barn
Produce 25,000 biofuel across all farms
Max upgrade a Water Bot
Grow a Giant Tomato
Max upgrade a Biofuel Bot
Build Forbic's House
Build Echo's Workshop
Earn 50,000 spare parts across all farms
Produce 5,000 biofuel across all farms
Move a building at least once
Earn 15,000 spare parts across all farms
Unlock 10 crops
Place at least one decoration
Build Sonnet's Shop
Spin the Cog a thousand times
Build Pinion's House
Produce 1,000 biofuel across all farms
Build Haiku's House
Play the game for 1 hour
Unlock a new crop
Spin the cog once
Play the game for 48 hour (across all farms)
Earn 10 MILLION spare parts across all farms
Produce 1 MILLION biofuel across all farms
Place down ten cows on one farm
Place down ten pigs on one farm
Build 666 crop tiles on a single farm
Unlock the Sandy Desert farm
Unlock the Blossom Forest farm
Unlock the Desert Oasis farm
Water 1 MILLION crops (across all farms)
Harvest 250,000 crops (across all farms)