Yellow is an unusual color for a monkshood, and this is the kind of light, fresh yellow that really shines in the shade. Add to that the fact that this monkshood has multi-branching stalks, and a bloom period that can last two months. And deer and rabbits won't bother them.

Aconitums are commonly known as monkshood, because the upper
sepal of each flower resembles the hoods of medieval monks. They
attract a variety of butterflies and moths, and are the primary food
source for Old World bees. Another common name, wolfbane, refers to the
poison made
from this plant's roots, which was used to tip hunting arrows.
Medicinal (and poisonous) uses of this plant date back to ancient times.
What's the difference between a medicine and a poison? Dosage.