Bug with Zyra's W /passive.

Im not exactly sure what triggers it, but sometimes when i press W to plant a seed while my passive is also open, it will take both seeds i have in store instead of just 1, and it will only spawn 1 plant as well. Otherwise there is 2 plants spawning in the same exact spot. idunno its just something weird i've been noticing, happening at least 4 or 5 times a game.