Hi I'm Karen Rodowicz with JK Flowers and I'm here to help you pick that perfect sunflower. As we all know sunflowers grow tall and are just a vision of the sun and that is where they get their name from. When they start to grow a stalk you will see the bloom come up. When the bloom slowly starts to turn its head you will see it look something like this and the bloom will slowly start to open. This is the perfect time to pick your sunflower. Depending upon the height you want your bloom to be depends upon where you cut your sunflower. If you like to put them in a tall vase you want to leave the stalk as long as it can be. Once you pick it, cut the stalk at an angle and place them in some lukewarm water and you'll have an arrangement that will last for at least a week if not more. Sunflowers are great in the Summer, they're great in the Fall and they're lots of fun to grow and just keep in your house. Once again I'm Karen Rodowicz and I hope this was helpful.