The rhubarb plants have begun flowering following an unusually dry April! Rhubarb usually blooms when the plant is under stress. Lack of water or food is usually the main reason, so remember to water the rhubarb during dry periods. I also put a pile of well-rotted chicken manure on the rhubarb clump every winter.
If you have a rhubarb clump that’s been there for a few years and it now flowering, you may need to lift and split the clump during the winter months. This will be like pressing the ‘reset’ button for the plant and will help create more growth in the future. It will also reduce the amount your rhubarb flowers.
Letting the rhubarb flower grow does not harm the plant, but remember that the energy of the plant now gets diverted from producing stems to creating flowers and seed heads which would significantly reduce the yield for the current growing season.
I am going to cut the flowers back to get the best crop of fresh rhubarb stems.