how and when should delphiniums be divided?
my delphiniums are too crowded and need to be divided,
Certified GKH Gardening Expert
Typically these are too short lived to consider dividing, but if they need thinning out, then that is better than letting them over crowd. Consult this artical for more information: https://www.gardeningknowhow.com/ornamental/flowers/delphinium/growing-delphinium-plants.htm