I have a castle in Krokotopia with a garden. Recently, I planted a white desparagus. After it reached maturity, it required sun among other things. After I gave it sun (level 1, 3 energy points), I figured the sun icon above the plant would go away. It did not. At the time, I was out of energy. Later, when I had full energy and gave it sun again. The sun icon still did not go away. I gave a level 2 sun (8 energy points) and the icon still did not go away. I gave it at least 7 sun spells with no effect to the sun icon.
Is this a glitch or is it suppose to be like this? I plant to increase me reagents, gold, treasure cards and whatever else they can provide me.