Caring for sunset hyssop (Agastache rupestris) is relatively easy once it is established. This plant does not respond well to over-watering, so it is important to keep it on the dry side once it has settled into its new location. This means that you should avoid watering it too frequently and allow the soil to dry out slightly between waterings. Sunset hyssop is a drought-tolerant plant and can handle periods of dryness without issue.
When selecting a location for planting sunset hyssop, make sure to choose an area that receives full sun or at least a warm microclimate. This plant thrives in sunny conditions and will perform best when it receives direct sunlight for most of the day. If you live in a cooler climate or have a shady garden, try to find a spot that gets the most sun possible or consider creating a warm microclimate by using a south-facing wall or reflective surfaces to maximize sunlight exposure.
In terms of pruning, it is generally recommended to wait until spring to cut back the old growth of sunset hyssop. This allows the plant to benefit from its dried foliage during the winter months, providing some protection and insulation. In early spring, you can cut back the old growth to the base of the plant or shear it down to the ground. This will encourage new growth and help maintain a neat and compact appearance.
In terms of maintenance, sunset hyssop is a relatively low-maintenance plant. However, it can benefit from a light application of organic fertilizer in the spring, which can help promote healthy growth. Be sure to follow the instructions on the fertilizer packaging and avoid over-fertilizing, as this can lead to excessive foliage growth at the expense of flower production.
One important thing to note is that sunset hyssop is a relatively short-lived perennial, typically lasting around three to five years. However, it is known to self-seed, so you may find new plants popping up nearby. If you want to encourage self-seeding, you can leave some spent flowers on the plant to allow them to develop seeds. Alternatively, you can collect the seeds and sow them in other areas of your garden.
Caring for sunset hyssop involves providing it with the right amount of sunlight, avoiding over-watering, and giving it a light pruning in the spring. With proper care, this beautiful perennial will continue to provide color and fragrance to your garden for years to come.
