Low lighting doesn't destroy crops immediately, block update required.

Crops planted in Minecraft are not immediately destroyed in low light, but the instant I put a block next to the crop (in this case, fully-grown wheat) the block gets destroyed normally.

This is not a huge issue and does not affect gameplay in a large manner. Just letting the Devs know. 

It is impossible to place anything on the block after the crops have been destroyed, until of course a light source has been placed nearby. 

Thank you for reading, and fix it someday.

P.S. Not sure if this is actually an intended feature or a bug, but I'm assuming it's a bug since it hasn't been mentioned anywhere.