Crops like carrots grow faster when planted in an alternating pattern with a secondary crop like wheat.

Steps to reproduce:

1. Place a source of water on the same layer as your farmland
2. Tilt your farmland around the water source in a 9x9 pattern
3. Plant carrots on your farmland and leave a space of 1 block row between each row of carrots
4. Plant wheat in each empty row of farmland
5. Those crops whil now grow faster than a full field of only one crop type