Are your flowers positioned in a hot spot with lots of sunlight?
Have your flowers recently been transplanted?
Do you grow bulbs like daffodils or gladioluses?
Do your flowers grow in acidified soil?
Some flowers are acutely sensitive to heat and extreme sun. Too much exposure to sun or heat drains the flowers of their bright colors. Many flowers prefer morning sun and filtered afternoon light. Try to find out if your flowers like less sunny conditions and protect them from the sun the next year.
Flowers can lose their vibrant colors when they are stressed. This usually happens if a plant has just been transplanted. Give the plant some time to adapt to its new location and the color should return with next blossoms.
Some bulbous plants, such as daffodil and gladiolus, tend to fade with age. Gardeners often dig up old bulbs and replace them with new ones once the flowers start fading and losing their vibrant colors.
Soil acidity may be responsible for altering or fading flower color. A popular example of this phenomenon occurs with hydrangeas that seem to be particularly sensitive to the amount of acid in the soil.
Most flowers are known to fade after pollination had finished, as they don't need to attract pollinators anymore. You shouldn't worry if this is the case, as it is a completely normal thing that flowers do.
https://www.gardeningknowhow.com/plant-problems/environmental/fixing-color-faded-flowers.htm
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Sreten null
Hi! I’m Sreten Filipović. I graduated from the Faculty of Agriculture at the University of Belgrade, with a master's degree in Environmental Protection in Agricultural Systems. I’ve worked as a researcher at Finland's Natural Resources Institute (LUKE) on a project aimed at adapting south-western Finland to drought episodes. I founded a consulting agency in the field of environment and agriculture to help farmers who want to implement the principles of sustainability on their farms. I’m also a founding member of the nonprofit organization Ecogenesis from Belgrade whose main goal is non-formal education on the environment and ecology. In my spare time, I like to write blog posts about sustainability, the environment, animal farming, horticulture, and plant protection. I’ve also published several science-fiction short stories.
You can find me on LinkedIn at https://www.linkedin.com/in/sreten-filipovi%C4%87-515aa5158/