Anise hyssop
Agastache foeniculum · Lamiaceae
Upright spikes of lavender-blue flowers from midsummer to autumn, over leaves that smell of aniseed. Bees and goldfinches work it constantly.
- Size
- 3 ft tall, 18 in wide
- Zones
- 4 to 8
- Light
- Full sun to part sun
- Flowers
- Early July to early September
- Pets
- No toxicity recorded
- Job in a bed
- Drift
A bed built around anise hyssop
The planner designed this bed around anise hyssop when this page was made: a 12 × 6 ft (3.7 × 1.8 m) cottage garden in zone 6, full sun. It chose the other plants from the 966 that suit those conditions, and says below why anise hyssop stands where it does.
The plants
- 1 Anise hyssop × 3, lavender
- 2 Winter heath × 6, pink
- 3 Mouse-ear coreopsis 'Nana' × 11, yellow
- 4 Sneezeweed × 4, orange
- 5 Silver sage × 1, silver leaves
- 6 Schubert's allium × 3, pink
- 7 Star of Persia × 5, purple
Why this plant
- The only spires. The others are bells, daisies and globes. Shape reads at a distance, where colours blur.
- The only lavender.
Why here
- Anchors a back corner. At 3 ft it is one of the taller plants here, and the tallest close the ends of the bed, where they stand in front of nothing.
- A step in the back row. Next to star of Persia (20 in): no two neighbours there are the same height, so the back steps up and down like a skyline.
- 3 plants in one group. Massed, one kind reads as a single shape. Scattered, it would look spotty.
Why now
- In flower for 10 weeks. From early July to early September.
- Fills a gap. For five of those weeks nothing else on the plan is in flower.
Planned as a cottage garden: 25 of the 25 plants (100%), bulbs aside, stand alone or in groups of no more than five, small enough for the kinds to mingle. The scheme leans cool (lavender, pink and purple) and uses yellow and orange for warmth. Mouse-ear coreopsis 'Nana' is planted in three places along the bed, which gives it rhythm.
The planner's own design check: 12 Excellent, 5 Good. It flags one thing to watch: Nothing on this plan is highly poisonous or an aggressive spreader.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where anise hyssop goes in a border
At 3 ft it belongs in the middle of a bed. In the planner's ten height classes it is medium tall (2½ to 3 ft).
Its job: drift. Planted in a small group of three or five, and repeated further along in the other number.
A dependable spire for the middle of a sunny bed, and one of the best plants for bees. It is short-lived but seeds itself, so let a few seedlings stand in for the parents.
- Pollinator and herb gardens
- A long-flowering vertical accent
- Prairie-style planting
What to plant with anise hyssop
Plants recorded as good partners for it, and what each pairing does:
- Purple coneflower: in flower together for 10 weeks, from early July.
- Black-eyed Susan: in flower together for nine weeks, from mid July.
- Little bluestem: its blue-green leaves are a setting for the flowers, before and after.
Questions about anise hyssop
Does anise hyssop need sun or shade?
Anise hyssop grows in full sun (6 or more hours of direct sun a day) and part sun (4 to 6 hours of sun, including some afternoon sun).
It wants ordinary well-drained soil, of average fertility, and little watering once settled.
What zones does anise hyssop grow in?
USDA zones 4 to 8. It is hardy to zone 4, which means it survives winter nights down to about −20 °F (−29 °C).
Above zone 8 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
When does anise hyssop flower in my zone?
In zone 5 it flowers early July to early September. As a summer flower it moves about half a week for every zone: earlier where it is warmer.
| Zone 4 | Mid July to early September |
|---|---|
| Zone 5 | Early July to early September |
| Zone 6 | Early July to early September |
| Zone 7 | Late June to early September |
| Zone 8 | Late June to early September |
Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.
How far apart should anise hyssop be planted?
18 in (45 cm) apart, from the middle of one plant to the middle of the next. That is about its full width, so each plant keeps its own outline.
It grows 3 ft (90 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many anise hyssop plants do I need?
At 18 in apart, set out in staggered rows:
- 5 to fill 10 square feet (about 1 m²)
- 7 for a single row 10 ft (3 m) long
- 17 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as a group of three or five, with a second group further along in the other number.
In the bed above, the planner used three in one group.
Is anise hyssop poisonous to dogs and cats?
No toxicity is recorded for dogs, cats, horses or people, according to NC State Extension.
"Not toxic" is not "edible": a pet that eats a lot of any plant can be sick.
Do deer eat anise hyssop?
Mostly not. NC State lists it as resistant to deer and rabbits. No plant is proof against a hungry deer in a hard winter, but this one is low on the menu.
Will anise hyssop spread?
It seeds itself about; the risk of it taking over is moderate. Self-seeds freely. Remove the spent flowers to limit seedlings.
What flowers after anise hyssop?
Anise hyssop is over by early September. These start as it finishes and carry the same spot on, so it never goes flat:
- Garden chrysanthemum: from mid September to late October, 24 in tall, to stand in front of it and cover its fading stems.
- Blue mistflower: from late August to mid October, 2½ ft tall.
- Blue-stemmed goldenrod: from early September to mid October, 2½ ft tall.
What does anise hyssop look like in winter?
Anise hyssop dies down, but leave the stems standing: the seed heads stand through the winter, and songbirds eat the seed. Cut them down in early spring, before the new shoots come.
Is anise hyssop good for bees and butterflies?
Anise hyssop is visited by bees, butterflies, hummingbirds and songbirds.
It is native to the United States and Canada.
More Agastache
- Hyssop 'Black Adder' Agastache 'Black Adder'
- Hyssop 'Blue Boa' Agastache 'Blue Boa'
- Hyssop 'Blue Fortune' Agastache 'Blue Fortune'
- Sunset hyssop Agastache rupestris
- Texas hummingbird mint Agastache cana
In these guides
- Deer-resistant perennials for full sun
- Rabbit-resistant plants
- Pet-safe plants for a sunny border
- Native perennials for pollinators
- Garden plants native to Canada
- Plants for hummingbirds
- Plants for butterflies
- Plants for bees
- Plants that feed garden birds
- Plants with spires: vertical accents
Every fact on record
- Type
- Perennial
- Size
- 3 ft (90 cm) tall, 18 in (45 cm) wide
- Plant
- 18 in (45 cm) apart
- Height class
- Medium tall (2½ to 3 ft)
- Place in the bed
- Middle
- Flowers
- Early July to early September; upright spires; lavender
- Leaves
- Medium texture, herbaceous; green
- Shape
- Upright, self-seeding
- Hardy in
- USDA zones 4 to 8
- Light
- Full sun, part sun
- Soil
- Average, well-drained
- Water
- Low
- Feeding
- None needed
- Family
- Lamiaceae
- Comes from
- North America
- Attracts
- Bees, butterflies, hummingbirds, songbirds
- Stands up to
- Deer, rabbits
Checked against NC State Extension and VASCAN (plants of Canada). Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.