Maturity and Quality
Delphiniums and larkspur are normally harvested with one to two open flowers on the spike. Avoid flowers with mildew-infected leaves. At least one to two flowers per stem should be fully opened at the time of purchase with no sign of flower fall. Make sure stems are rinsed prior to re-cutting and arranging, so as to remove dirt and debris.
Grading and Bunching. There are no formal grade standards for larkspur and delphinium. Flower number per spike, stem length, stem straightness, and foliage quality are important quality attributes in these flowers. Larkspurs are normally bunched by size with an average of 10 stems per bunch.
Postharvest Handling and Storage
Delphinium and larkspur should be stored at 0-1°C. For longer term storage, they should be wrapped in perforated polyethylene to reduce water loss.
Delphiniums are very sensitive to ethylene, which causes rapid loss of all the flowers on the spike.
Pretreatments
Flower spikes should be pretreated with 1-MCP or STS to extend their vase life and protect them from exposure to ethylene. Because flowers are on spikes and are therefore at different maturity stages at the time of anti-ethylene treatment, STS may be a more effective anti-ethylene treatment than 1-MCP.
Packing
These flowers are often packed in hampers with or without water, but may also be packed in standard horizontal boxes. They are somewhat sensitive to gravity, so horizontally-packed flowers should be pre-cooled and maintained at proper holding temperatures.
Special Considerations
Flowers called larkspur or delphinium often are named incorrectly.
Disorders
Description
Delphinium, Consolida spp. The tall spikes of delphinium and the smaller spikes of larkspur are important accent flowers, with colors ranging from white through pink, purple and blue.