Zinnias flowers

Zinnias come in a variety of colors and grow large blooms. With full sun access, these flowers can reach up to 4 inches in height. "This is a flower we recommend giving a 'pinch' when they reach 12 to 18 inches tall to promote branching and flowering on the plant," say the O'Neals. "The more you cut zinnias, the more blooms they produce."

Do note that you should cut a zinnia when it's fully mature. The best way to tell that it's reached this point is by giving it a wiggle test, they say. Bounce the stem between your index and middle finger, and if the stem is rigid, it's ready to be cut. When the stem is floppy, it's not ready to cut and won't stand up straight in the vase. After cutting your zinnias, they will last for about seven to 10 days, however, they are known as a "dirty" flower, say the O'Neals. "Their stems are hairy, so they make vase water murky quickly," they say. "We recommend changing the water for a vase with these flowers once a day, retrimming the bottom of the stems each time."