Minecraft wiki entry for Sugar_Cane, associated text: Sugar cane can generate naturally up to four blocks tall, but short plants grow only to a height of three blocks, adding a block of height when the top sugar cane block has received 16 random block ticks (i.e. on average every 18 minutes on Java Edition or 54 minutes on Bedrock Edition, but the actual rate can vary widely). Sugar cane must be planted on a grass block, dirt, coarse dirt, rooted dirt, podzol, sand, moss block, mycelium, red sand or mud‌[upcoming: JE 1.19] that is directly adjacent to water, waterlogged block, or frosted ice (not merely above or diagonal to water), or on top of another sugar cane block. The adjacent water block can be covered with another block, whether opaque or transparent, and sugar cane can still be placed and grow next to it. Sugar cane grows regardless of light level, even in complete darkness.