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smallleaf giant hyssop

Agastache parvifolia · Lamiaceae

smallleaf giant hyssop (Agastache parvifolia)
Photo: no rights reserved · CC0 · via iNaturalist

smallleaf giant hyssop (Agastache parvifolia) is a perennial herbaceous plant in the Lamiaceae family. It is native to North America. USDA records it as hardy in zone 4 and warmer, down to about -23°F.

At a glance

Typeforb-herb Derived
Lifecycleperennial USDA
Native statusnative USDA
Mature height2 ft USDA
Lightfull-sun USDA
Water needlow USDA
Growth ratemoderate USDA
Soil pH5.6–6.2 USDA
BloomMay–June USDA
Flower colorRed USDA
Hardiness zones4 and warmer USDA
Guild layerherb-layer Derived
Nursery availabilityNo Known Source USDA

USDA quoted from the USDA PLANTS database · Derived computed by a fixed rule from those columns. No value on this page is estimated.

Growing conditions

It needs full sun. USDA rates it as having low water needs once established. Its drought tolerance is rated high. It is recorded on soils from pH 5.6 to 6.2 — acidic ground. Its cold limit is zone 4.

Size and growth

At maturity it reaches about 2 ft, making it about knee height. It grows at a moderate rate.

Bloom period

USDA records a bloom period of May through June. Flowers are red.

A flowering date, not a pollinator rating.

Foliage, flower and season

Summer foliage is dark green, coarse in texture. Its flowers are conspicuous. Its active growth period is spring and summer. USDA rates its lifespan as moderate.

What the site needs to provide

USDA records it across sites receiving 12 to 65 inches of annual precipitation. The low end of that band is genuinely arid, so it has a wide tolerance for dry country. It needs at least 130 frost-free days to finish its season. It roots to at least 12 inches. Fertility requirement: low — no feeding needed on ordinary garden soil.

Propagating it

Propagate it from seed and sprigs. USDA records no cold-stratification requirement, so seed should germinate without a chilling period. Its seed spreads at a slow rate. It spreads vegetatively at a slow rate.

Resilience and wildlife

Browsing animals rate it barely palatable — the sourced basis for calling it deer-resistant. Its fire tolerance is rated medium. Its growth form is recorded as rhizomatous.

Role in a guild

Herb layer. In a layered planting this is the herbaceous middle — perennials and grasses that fill the space between ground cover and shrubs. The layer is derived by a fixed rule from growth habit and mature height.

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Tags

deciduousdrought-tolerantsandy-soildeer-resistantacidic-soilnativefull-sun

Related plants

Others in Agastache

Similar role and hardiness

Where this data comes from

Every value on this page comes from the USDA PLANTS database record for symbol AGPA2, or is computed from those values by a fixed rule. Nothing here is estimated or model-generated. Where USDA publishes no value, this page omits the claim rather than filling the gap.

Read our full data sources and methodology.

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