In HappyLand, each season lasts 1 week (168 hours) compare to the real season.
Day 1 to 7 is spring - Sunny weather with a higher chance of rain, springtime is an ideal condition for the cultivation of plants
Day 8 to 14 is summer - Dry weather, plants, and water need more water to grow. There is a higher chance of storms.
Day 15 to 21 is autumn - Cool weather, high chance of hail, storm, and strong rain
Day 22 to 28 is winter - Cold weather, you can only grow specific types of plants during this weather, snowing also causes the yield to decrease
Note: All in-game plants will be reprogrammed to have season-dependent effects. Growing a plant in its optimal season will result in no loss of production yield or a slight produce yield increase from 1-2%. The price of products will change depending on the season. For example, watermelons will have a higher price in winter since it’s a summer fruit. However, growing watermelons in the winter season will yield less produce than in the summer.