Lavender Hyssop

Family: Lamiaceae Herb

Aromatic as a summer breeze, Lavender Hyssop blooms with cool, violet-lavender spires that perfume the garden from morning through dusk.

The leaves are softly textured and pleasantly resinous, offering a fragrant, floral-herbal character that shines in bouquets, infusions, and savory blends. Grow this 90-day favorite for a long season of showy color and a steady harvest of aromatic foliage to delight the senses all summer long.

Light: Full SunMaturity: 90 DaysHabit: Upright

Botanical illustration of Lavender Hyssop

Planting schedules and alerts are optimized for Columbus (Zone 6b).

Crop Dates

Milestone	Date
Start Indoors	Mar 14th
Last Frost	Apr 25th
Transplant / Sow Outdoors	Jun 20th
Harvest Begins	Sep 18th
Harvest Ends	Oct 16th

Crop Details

Trait	Value
Days to Maturity	90
Sun Requirements	Full Sun
Growth Habit	Upright
Support Needed	Stake
Planting Depth	Normal
Germination Temp (°F)	70
Min Soil Temp (°F)	50
Min Night Temp (°F)	50
Harden Off (days)	7

Culinary Notes

Chef's Note

Lavender hyssop has that unmistakable cool, mint-family snap, but it wears it with a floral, slightly resinous edge—so go in light and let it bloom. It’s at its best where aromatics can diffuse (infusions, syrups, and warm drizzles) rather than where it’s boiled hard.

Best Uses

steeped in hot tea or cold infusions for a violet-minty perfume
brushed or rubbed into roasted meats and poultry rubs (use lightly)
stirred into herb syrups or honey for late-summer cocktails and glazes
folded into vinaigrettes and marinades where you want a fragrant, not overpowering, herbal lift

Flavor Profile

cool minty aromatics lightly sweet floral note resinous herbal bite soft leaf texture with a fragrant finish

Kitchen Pairings

honey lemon olive oil butter vanilla lamb

Frequently Asked Questions

What pest or disease is most common on Agastache foeniculum (lavender hyssop), and how can I fix it?

Lavender hyssop commonly develops powdery mildew (a white, dusty coating) in humid conditions or with poor airflow. Water at the soil line, space plants so air circulates, and remove the most affected leaves early; if mildew persists, spray a labeled horticultural fungicide following label directions. Avoid frequent overhead watering and keep the plant from staying wet overnight.

How often should I water Agastache foeniculum during the main growing phase?

During active growth (from when plants are established until late summer), water deeply about once or twice per week, then let the soil dry slightly between waterings. Aim for evenly moist but never soggy soil—water stress is preferable to waterlogging because Agastache can suffer root problems in wet conditions. In full sun, check the top few inches of soil; if they feel dry at that depth, water again.

How do I tell when Agastache foeniculum is ready to harvest?

Harvest when flower spikes are mostly open—typically mid- to late-summer—and the individual florets along the spike look fully formed. For best flavor and scent, cut in the morning after dew has dried but before the hottest part of the day. If you want seed later, leave some spikes on the plant to mature and dry instead of cutting them all.