To my mind if you want larkspur for cutting, go for Giant Imperials. They have great height, large flowers, strong stems and lush feathery foliage… just the jolly job.
These are also great to just be left in the border for a cottage garden vibe… this is old school chic at its best.
*Height 90 cm
*300ish seeds in a packet
*Sow March-May and August-October Stick them in the fridge for ten days before sowing to aid germination.