Anise Hyssop Seeds - Agastache foeniculum

3, 4, 5, 6, 7, 8, 9

USDA Zones 3-9: Grows as a hardy, herbaceous perennial in this range. It dies back to the ground after a hard frost and re-emerges vigorously from the roots in spring. It can be grown as a fast-growing annual in any zone, as it typically flowers in its first year.

Best Performance (Zones 4-8): Thrives in these zones, establishing strong root systems to survive cold winters and returning larger and more robust each year. Provides a long-lasting, reliable flower show from summer to fall.

Northern Zones (3-4): Exceptionally cold-hardy. Will reliably survive the winter, even in Zone 3. A 2-inch layer of fall mulch (straw or shredded leaves) is beneficial to protect the crown during the first winter as it gets established.

Hot Climate Zones (8-9): Very heat-tolerant if it has good air circulation and excellent drainage. It dislikes high humidity combined with wet, heavy soil. In Zone 9, afternoon shade can be beneficial, but it may perform as a short-lived perennial.

Soil Temperature (for Germination): Requires soil temperatures between 65-70 degrees F for germination. Can be slow and erratic to sprout, so patience is key.

Growing Season (Perennial): As a perennial, it has an indefinite growing season. From seed, it will grow vigorously and often flower in its first year. It reaches full maturity and peak bloom in its second year.

Learn more about USDA Hardiness Zones here

When to Plant (Indoors):

Recommended Method: Start seeds indoors 6-8 weeks before your average last frost date.

When to Plant (Outdoors):

Direct sow in early spring after all danger of frost has passed, or in late fall to allow the seeds to naturally stratify over winter.

Where to Plant:

Sunlight: Full sun (6+ hours per day) is best for the strongest plants and most prolific blooms.

Soil (Critical): Must have well-drained soil. It thrives in average, loamy, or even slightly sandy soil. It will fail in heavy, dense clay or soil that stays wet, especially in winter, as this causes root rot.

Soil pH: Prefers a soil pH between 6.0 and 7.5.

How to Plant (Seed Starting):

Stratification (Recommended): For best results, cold-stratify your seeds. Mix the seeds with a small amount of damp sand or a moist paper towel, place them in a plastic bag, and refrigerate for 4 weeks before planting.

Depth (Critical): Seeds need light to germinate.

Process: Press the seeds (stratified or not) firmly onto the surface of a sterile, moist seed-starting mix. Do NOT cover them with soil, or cover extremely lightly with 1/16 inch of fine soil or vermiculite.

Germination: Keep the soil mix moist (but not soaking) at 65-70 degrees F. Be patient; germination is slow and can take 14-30 days.

How to Plant (Transplanting):

Harden Off: Acclimate your indoor-sown seedlings to outdoor conditions for 7-10 days before planting them in the garden.

Spacing: Space plants 12-18 inches apart to allow for good air circulation, which helps prevent mildew.

Growing and Care:

Watering: Water regularly during the first growing season to help the plants establish a strong root system.

Drought Tolerance: Once established (after the first year), Anise Hyssop is very drought-tolerant. Water deeply but infrequently during extreme dry spells.

Fertilizing: This plant thrives in average soil and does not need heavy feeding. Avoid high-nitrogen fertilizers. Amending the soil with a little compost at planting is all it needs.

Deadheading: You can deadhead spent flowers to encourage a second, lighter bloom. However, leaving the seed heads provides food for finches and other birds in the winter.

Controlling Spread: Anise Hyssop will self-seed readily. If you do not want it to spread, be sure to cut back the flower stalks before the seeds ripen and drop.