Technically speaking, maximum efficiency can always be at 100 % . comparing this fact to the growth rate of hay grass in rimworld, I observed growth rate to be 140%. this is only for that specific haygrass. neighbouring hay grass's growth rate is 100%.

Why is that hay grass growing at 140%?

Edit: earlier i had thought that was a bug. But from the answer below it is clear.

I am using vanilla rimworld 0.14.1234

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1 Answer

Without selecting anything, hover over the soil the plants are planted in to see what type of terrain it is on and the growth rate in the bottom-left corner.

Rich soil provides the 140% growth rate bonus. Regular soil is the 100% growth rate and other terrain types will have varying levels of growth from 0% to 140%.

Judging from your picture, the darker spots of soil are more likely to have a higher growth rate than the others. Again, you can see the name of the soil type in the bottom-left corner if you hover without selecting anything.

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