Puja corners tend to be warm, with diyas, incense and sometimes a closed room full of people. Add a spot of direct sunlight, and the flowers dry out quickly and lose their bright colour. Keep your marigolds away from sunny windowsills, ovens and the flame itself, which is also a safety matter, since dry petals and garlands catch fire easily. Place them in a cool, shaded part of the room instead, and put them out for the puja only when you need them, then move them back.
