Enter your ZIP to see whether this is legal to plant in your state, and whether it survives your winter.
Giant hyssop is rated fire resistant, though the support comes from a limited set of extension recommendations.
Extension specialists in Oregon, Washington and Idaho list Agastache as fire resistant. Oregon State also profiles hummingbird mint among perennials chosen for fire-resistant landscapes, while the University of Arizona lists hummingbird mint or hyssop as a fire-resistant plant for Yavapai County. The agreement reaches across the Pacific Northwest and Arizona, but all three findings are expert-curated recommendations rather than laboratory measurements.
The Arizona guidance adds an important condition: Agastache is considered resistant when irrigated and maintained. Its fire-resistant category means it tends to resist ignition under those conditions, not that it cannot burn. The sources do not provide a test score or measured ignition threshold that would turn that recommendation into a guarantee.
Giant hyssop is a perennial in the mint family, Lamiaceae. For plant selection, the extension guidance supports treating it as a fire-resistant choice, provided its irrigation and upkeep match the conditions behind that rating.
Form
perennial
Rated in
OR/WA/ID; Pacific Northwest (Oregon / Washington / Idaho); Yavapai County, Arizona
On this lot
1. Fire evidence and conditions
Fire evidence
Fire-resistant — location does not change the cited classification.
The October 2023 joint Pacific Northwest Extension publication explicitly names Oregon, Washington, and Idaho and publishes more than 150 plant profiles. FireApproved has normalized 155 exact plant records from the source; publication scope does not assert that every listed plant suits every site within the three states.
Yavapai County (AZ footprint); partial normalized coverage · 2025-03-14
University of Arizona Cooperative Extension authors Bulletin 34 for Yavapai County. FireApproved publishes 198 exact source owners from its resistant and prone tables and keeps the county boundary visible. County publication scope is regional Arizona context, never statewide scope.
2. Why this plant is relevant here
State distribution
Documented in ID, OR, WA.
Native range
Introduced / established
USDA hardiness
Documented range 4–8.
3. Legal, ecological, and broader status
Legal-list status
Seed-list status
Reported invasive here
Broader regional context
Federal context
How to read this page
The status above is computed from the cited rows below: independent recommendations can support a fire-resistant result, an avoid row can produce keep-away, and disagreement stays visible as conflict. Placement notes preserve each source’s own scheme rather than translating unlike rules into one scale. This is evidence about a plant, not permission to plant it in every part of the defensible space; Zone 0 remains noncombustible.
Plant hardiness evidence
These values describe the plant source. Your ZIP zone comes from the separate 2023 USDA
Plant Hardiness Zone Map. Whole-zone values stay whole-zone, and a single unresolved value
is not treated as a tolerance range. Different source boundaries stay separate: overlapping
statements are compared independently, while only ranges with no shared zone are called a conflict.
4–8 explicit range · whole zone precision · source stated
Source taxon: Agastache spp. · exact match.
Source location: Hummingbird mint profile, USDA hardiness zones field.
Where its sources say to plant it
Placement rules below use each source's own distances or named zones, tied to its rating.
They are not interchangeable with the directory's current Zone 0 guidance.
Fire-resistant plant profile galleries: Hummingbird mint — Agastache spp. [osu-2023-perennials-gallery] (with its recommendation)
The evidence
Grouped by what each source concluded. Primary evidence rated the plant itself
(a lab, field program, or original curation); corroboration compiled or
republished another source's rating and resolves to its root lineage.
Listed as Hummingbird Mint, Hyssop — Agastache sp.. The bulletin says fire-resistant plants tend to resist ignition when irrigated and maintained, while fire-prone plants may ignite readily and burn intensely.
