I had one that died from drought, so I would say they do need irrigation. Maybe not as much as a hydrangea, but some, for sure.

Thanks, hoovb. I'll be sure it gets what it needs, not too much. Our clay soil may help.

They are not at all particularly water-hungry. They originated in periodically droughty areas of south Africa but have very fleshy roots that are adapted for water storage so can tolerate dry times once properly established. They would need no more than "average" water availability. And well draining soil.

Kniphofia are not that picky. They grow wild in the woods where we are with zero water in the severe drought we are having. I dig them up to get them out of the garden so they stay in the woods. The soil is pretty much heavy well draining clay. Maybe the hybrids are a bit more touchy. Best way to find out is to try one. They need water to start but the ones all over here certainly are not sitting in water. It is dry as a bone out there right now.

My experience has been that the plain old fashion knifphofia uvaria are extremely hardy without much water, especially out at the coast but look a much better with water inland.
The newer hybrids , especially the new 'popsicle series' are not as hardy and much more temperamental with water and sun requirements.
I planted k. shining sceptre in full sun and clay soil about 6 years ago in Mill Valley CA and its been doing well despite what I think is crappy garden maintenance care. ( inept maintenance gardeners that have an aversion to the irrigation clock)
pictured below is a coastal garden with K. popsicle red . It receives irrigation 2 days a week for about 10 minutes.