What You Did
You turned white flowers or celery stalks into colorful flowers or stalks.
Your flowers, or celery, absorbed the dyed water using capillary action, which is the means that all cut flowers absorb water, allowing them to remain alive long after they are cut off from their roots. Capillary action occurs in flowers because the water molecules are more attracted to the inside surface of the stalks than each other. The food dye particles are drawn up into the stalk along with the water, but when the water transpires away from the outer surface of the plant, the dye remains behind.
Using less food dye or cold water may make for less bright flowers. Using a nonwhite flower will produce a different result. The brand and color choice of your dyes will produce different results, with red generally being more effective than blue, which is more effective than green.
Compare different brands, types, or colors of dye. Try blending different colors together. Try different temperatures of water Try different kinds or colors of flowers. Try using more or less than 30 drops of food color
transpiration, capillary action