In your rocking chair on your front porch last week you were bummed about the dandelions in the lawn but enjoying the tulips. I pulled out 523 dandelions and I now have dandelion thumb so I have changed my mind. Dandelions now look pretty and I’ll leave the rest alone.
So now I just enjoy both of them and for two plants that don’t move around much (rumors that dandelions walk across streets and into your lawn are unfounded) they sure open and close a lot.
Tulips seem to open up each day because it warms up. I guess evolution has told them that the pollinators are going to be more active in the afternoon. Then they close back up. Dandelions seem to be smarter. If it gets cold they close. But even if it gets cloudy they seem to close up before the rain beats them up unlike tulips.
So I have to go find a paper and sure enough, the Journal of Experimental Botany has a paper that explains it all and they mention tulips and dandelions a lot. Duration of darkness, osmotic pressure, all that good stuff about how and when a flower opens.
Or you can enjoy your morning coffee this weekend and watch your tulips and dandelions open up again.
This animation is from Tulip Test Gardens which has a lot of good info about your tulips. (Click to animate again.)