Grayson's sunflower is 46 inches tall.
Luca's sunflower is 3 inches taller than Grayson's sunflower.
Izzy's sunflower is 6 inches shorter than Luca's sunflower.
How tall is Izzy's sunflower?
Luca's sunflower is 46 + 3 = 49 inches tall.
Izzy's sunflower is 49 - 6 = 43 inches tall.
Thus, Izzy's sunflower is 43 inches tall.