Anise Hyssop (Agastache foeniculum) is a versatile, fragrant perennial herb in the mint family. It is celebrated for its upright spikes of lavender-blue flowers and foliage that releases a distinct licorice or anise scent when brushed. Anise Hyssop is a powerful magnet for beneficial pollinators, drawing bees, butterflies, and hummingbirds throughout the summer months. Successful cultivation relies on understanding its specific site requirements and providing consistent, low-maintenance care.
Preparing the Site and Planting
The plant thrives best in full sun, requiring a minimum of six hours of direct sunlight daily, though it tolerates light afternoon shade. The ideal soil is consistently well-drained, which prevents root rot in waterlogged environments. Anise Hyssop is adaptable to average or poor soil, but heavy clay soils should be amended with compost or sand to improve drainage before planting.
Gardeners can start the herb from seed or use nursery starts. Seeds benefit from cold, moist stratification to improve germination rates. Sow seeds very shallowly or press them onto the soil surface, as light is needed for sprouting. Start seeds indoors six to eight weeks before the last expected frost for earlier spring transplanting. Nursery starts should be set into the garden at the same depth they were growing in their original containers.
Proper spacing ensures good air circulation and room for mature growth, which typically reaches two to four feet in height. Space individual plants 12 to 24 inches apart, depending on the variety, to allow the clump-forming perennial to fill out. After placing the plant in its prepared hole, gently firm the soil around the base and water thoroughly to settle the soil and eliminate air pockets. This encourages the deep, anchoring root system necessary for long-term health.
Routine Care
Once Anise Hyssop is established, its maintenance requirements are minimal. New transplants require regular watering, about one inch per week, during the first growing season to help the root system take hold. Afterward, the plant becomes drought-tolerant, requiring supplemental watering only during extended dry spells. Avoid overwatering, as saturated soil is the primary cause of root problems.
The plant performs well without added fertilizers in average garden soil. Excessive fertilizer can lead to lanky growth and reduced flowering. If the soil is poor, a light application of balanced, slow-release organic compost around the base every one to two years is sufficient. This minimal feeding strategy supports strong stems and abundant flower production.
Pruning is important to maintain a compact shape and encourage continuous blooming. When the plant is young, pinching back the growing tips encourages lateral branching and a bushier appearance. Deadheading spent flower spikes throughout the blooming season promotes new flowers and extends the bloom period into the fall. In early spring, before new growth begins, the entire plant can be cut back by up to one-third to remove old, woody material and rejuvenate the plant.
Anise Hyssop is resistant to most common pests and diseases. The aromatic foliage acts as a natural deterrent to many insects, and deer avoid it. In environments with high humidity or poor air circulation, watch for powdery mildew, a fungal disease appearing as a white, dusty coating on the leaves. Adequate spacing and avoiding overhead watering helps prevent this issue.
Harvesting and Utilizing Anise Hyssop
Harvesting at the optimal time ensures the leaves and flowers contain the highest concentration of essential oils. For the strongest flavor, harvest the leaves just before the plant begins to flower, when the oil content is nearing its peak. Both leaves and flowers can be harvested throughout the entire growing season. Use clean shears to cut the stems down to a leaf node, taking no more than one-third of the plant at any single time. This technique allows the plant to quickly recover and produce more material for subsequent harvests.
Harvest in the morning, after the dew has dried but before the heat of the day, as the volatile oils are most concentrated in the foliage. The harvested leaves and flowers can be used fresh or preserved. To dry the herb, gather the cut stems into small bundles and hang them upside down in a cool, dark, and well-ventilated area until the leaves become brittle. Once dried, the material should be stored in airtight containers away from light and heat to retain its flavor.
Uses for Anise Hyssop
The dried leaves and flowers are commonly used for:
- Brewing a soothing herbal tea.
- Adding to potpourri mixtures for their sweet, licorice-like aroma.
Fresh leaves provide a unique, subtle flavor to:
- Salads.
- Fruit dishes.
- Baked goods.