Hyssop seeds are best sown outdoors in the spring, after the last date of frost, when the earth has warmed up. For earlier establishment in colder locations, start seeds within 6 to 8 weeks before the final date of frost. Once the risk of frost has passed, transplant the seedlings outside.
Hyssop can also be propagated using stem cuttings in early summer. Take 4- to 6-inch cuttings from healthy, non-flowering stems. Cut off the lowest leaves, then plant the cuttings in potting soil or well-draining soil.
Regardless of the method used, hyssop requires well-drained soil and sunny location to thrive.
Hyssop seeds take 1 to 3 weeks to germinate after which their seedlings appear from the ground. They need sufficient sunlight and routine watering at this stage to sustain their growth, and must be shielded from freezing cold and severe temperatures.
The seedlings develop a robust root system as they get older and begin to make leaves on an upright stem. The plant concentrates on leaf development and general vegetative growth during this stage.
In its second year of growth, hyssop plants typically reach maturity and begin to produce flowers. Typically, the flowering season occurs in the summer. Hyssop has tiny, tubular flowers that are available in a range of hues, including blue, purple, pink, and white. The plant's reproductive cycle is aided by the pollinators that the flowers draw, such as bees and butterflies.
After pollination, the flowers transform into seed pods, containing seeds. Being a perennial plant, it can survive for several years with proper care and upkeep, giving a consistent supply of fragrant leaves and vivid flowers.