Hydrangea flowers are known to change color based on soil pH. In acidic soils, they tend to produce blue or purple flowers, while in alkaline soils, they lean towards pink or even red.
Morning glories are known for their vibrant blue flowers, but they can also appear in shades of pink, purple, and white.
Some African violet cultivars exhibit a phenomenon called "chimerism," where their flowers have multiple colors due to genetic variations.
While roses don't change colors drastically, some varieties have petals with color gradients or "stripes," which can give the appearance of color change.
Some orchids have flowers that change color as they age. For instance, an orchid might start with white flowers that gradually turn pink as they mature.
The petals of the butterfly pea flower can change color depending on the pH of the liquid they're steeped in. They are often used to create vibrant blue or purple teas.
Some clematis flowers change color as they open, starting with one color and transitioning to another as they age.
Certain hibiscus flowers can change color from pale to deep shades as they mature.