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