Thumb flower

In the magical world,
There's a flower called the Thumb flower,
Which's blossom as tiny as your thumb,
But don't be fooled!
The stem grows tall up to one meter two,
And the tallest can reach one meter six,
Or even one meter seven.

Each flower holds its own special magic,
Starting as pure white when it's young,
And at eighteen, it blooms with magic colors all its own.