Agastache (Yellow)

Yellow- to greenish-yellow-flowered Agastache occurs among the species and hybrids in this aromatic perennial genus. Mature height, hardiness, and moisture needs vary across the group, so plan around the named selection when one is available. ## Flowering and landscape use North Carolina Extension describes Agastache as clumping perennials with showy flower spikes that bloom mostly through summer. Flower colors vary by species and hybrid; yellow forms add vertical color to sunny borders, containers, and pollinator plantings. ## Site and size Full sun and well-drained soil suit many garden forms, though tolerance varies by species. Colorado State Extension lists examples from about 18 to 36 inches tall. Allow space for the selected plant’s spread and check its hardiness before planting in cold sites. ## Maintenance Water during establishment and adjust irrigation to soil and weather after roots settle. Keep crowns out of waterlogged winter soil. Agastache flowers attract bees, butterflies, and hummingbirds, while aromatic foliage may release scent when brushed. [North Carolina Extension](https://plants.ces.ncsu.edu/plants/agastache/common-name/hummingbird-mint/) summarizes the genus and its garden uses; [Colorado State University Extension](https://extension.colostate.edu/resource/herbaceous-perennials/) illustrates variation in size and flower color among species and hybrids. The [Royal Horticultural Society profile of yellow giant hyssop](https://www.rhs.org.uk/plants/49099/agastache-nepetoides/details) documents yellow-flowered Agastache as one species example.