Lupines revert to pink
I have very healthy lupines. However, I have set pink yellow and blue/white dwarf. They all thrive but all change to pink after a few years. What do I do for new plants to sustain their color? This year I have loads of pink lupines and 1 yellow and one pale blue left. Why? Do I have to add something to the soil?
Color change in mature lupines is normal. Oftentimes, lupine flowers change color when they have been pollinated. In addition, existing soil conditions and cross-pollination can cause colors to fade and change from the original over time, with hybrid types even reverting back to the original color from which the plant initially derived.