Daily Light Integral Influences Rooting of Herbaceous Stem-tip Culinary Herb Cuttings

Domestic production of culinary herbs continues to increase in the United States. Culinary are primarily propagated by seed; however, some have poor germination rates and slow growth. Thus, there advantages propagating vegetative stem-tip cuttings as they lead true-to-type plants a shortened time. Previous research ornamental young finished shown reduction rooting time increases plant quality with photosynthetic daily light integral (DLI). To our knowledge, little no has addressed how DLI influences herb liner quality. Therefore, objectives this study were quantify morphological traits five economically important when grown under DLIs ranging from 2.8 16.4 mol·m −2 ·d −1 . Stem-tip Greek oregano ( Origanum vulgare var. hirtum ), rosemary ‘Arp’ Rosmarinus officinalis sage ‘Extrakta’ Salvia spearmint ‘Spanish’ Mentha spicata thyme ‘German Winter’ Thymus vulgaris ) excised stock rooted shade or aluminum shading 36%, 56%, 76% create range treatments. After 9 days (spearmint) 16 (all other genera) treatments, root, shoot, total dry mass all liners generally increased 105% 449%, 52% 142%, 82% 170%, respectively, genus-specific optimums. Stem length oregano, spearmint, decreased 37%, 28%, 27%, However, stem unaffected DLI. The index genera was greatest at 10.4 Furthermore, ≤6 had low root shoot accumulation; taller. between 10 12 should be maintained during propagation, because ≥16 may deleterious energy inefficient if supplemental lighting use is increased.