Enter your ZIP to see whether this is legal to plant in your state, and whether it survives your winter.
Yes, mock orange is rated fire resistant, with all six sources reaching a favorable conclusion.
Their methods differ, but none places the shrub on the unfavorable side.
Idaho Firewise supplies the numerical result. Its field-trial database scores mock orange 8 of 10. That score rates fire resistance, while most of the other sources make a yes-or-no judgment through inclusion on a fire-resistant plant list.
FireSmart BC approves mock orange as a fire-resistant plant. OSU, WSU, and University of Idaho Extension list it as fire resistant, while Montana State University Extension and the King County Forestry Program recommend it in their fire-resistant shrub guidance. For its compilation, the University of Nevada Cooperative Extension draws on seven western source lists; mock orange meets its requirement for favorable assessments from at least two.
Mock orange is a shrub in the hydrangea family. The OSU, WSU, and University of Idaho Extension guidance gives it a hardiness range of USDA zones 4a through 8b. Taken together, the field-trial score, approved-plant chart, expert lists, and multi-source compilation support treating mock orange as a fire-resistant landscape plant.
Form
shrub
Rated in
Australian Capital Territory, Australia; British Columbia; Michigan / Great Lakes; Montana / Northern Rockies +8
On this lot
1. Fire evidence and conditions
Fire evidence
Fire-resistant — location does not change the cited classification.
Australian Capital Territory, Australia; British Columbia; Michigan / Great Lakes; Montana / Northern Rockies; Nevada / Great Basin; OR/WA/ID; Oregon; Oregon (Willamette Valley); Pacific Northwest (Oregon / Washington / Idaho); Yavapai County, Arizona; southern Idaho / Intermountain; western WA
Maintenance
Typed publication scope: 8 scopes across 8 cited fire sources
Southern Idaho (ID footprint); partial normalized coverage · 2013-11-08
The official database labels itself "For Southern Idaho" and describes Idaho residents at the urban-rangeland interface. FireApproved publishes 419 existing plant owners that cite its scored rows. This bounded Southern Idaho scope is regional context, not statewide coverage or a conclusion that the score transfers unchanged to every Idaho site.
King County's current wildfire page links this list for the Puget Sound Basin. FireApproved publishes 82 exact source owners as basin context, not statewide Washington guidance or a site-specific recommendation.
Michigan State University Extension Bulletin E2948 is explicitly a list of wildfire-resistant landscape plants for Michigan and includes a Michigan-native field. FireApproved publishes 221 exact GBIF owners from 226 represented source rows and holds 15 complex or non-exact rows. This dated publication scope is not a current site-suitability determination.
The April 2022 MontGuide explicitly presents fire-resistant species adapted to Montana. FireApproved publishes 92 exact plant records from the source while retaining excluded genus, family, and unresolved rows; the guide itself says not every listed species grows in every part of the state.
Willamette Valley (OR footprint); partial normalized coverage · 2015-02-01
OSU Extension says EM 9103 highlights fire-resistant plants that thrive under Willamette Valley growing conditions. FireApproved publishes 172 exact owners only as valley context. The guide shares the PNW 590 lineage and is not a second independent vote or statewide site clearance.
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.
University of Nevada Cooperative Extension compiled plants suited to Nevada climate zones and reported favorably by at least two upstream firewise lists. FireApproved publishes 126 exact source owners at Nevada publication scope. The source explicitly makes no independent flammability determination, so these rows remain corroborative.
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.
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 Resistance of Plants Master Database: plantable at 30' from home [Idaho minimum planting distance] (with its recommendation)
FireSmart BC Plant Program: suitable for HIZ intermediate zone (10-30 m) [FireSmart BC Home Ignition Zone] (with its recommendation)
Fire-Resistant Plants for Oregon Home Landscapes: Oregon [osu-frn6-oregon-regions] (with its recommendation)
Fire-resistant Landscape Plants for the Willamette Valley: Mock Orange profile (PDF page 136) [osu-em-9103-profile] (with its recommendation)
Oregon State Fire Marshal: Mockorange [osfm-fire-resistant-quiz] (with its recommendation)
Canberra Plant Selector: filtered result page 13 [canberra-selector] (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.
“Fire-Resistant Plant Materials for Oregon”
· condition: green
Philadelphus species (Mockorange) is listed under “Shrubs—deciduous”. The guide says most listed plants require some irrigation during Oregon's dry summer months and must be maintained in a healthy condition.
OSFM quiz result “Mockorange” says: Dense green foliage and lower resin content can make deciduous shrubs useful in more fire-conscious landscape design.
Listed as Mock orange — Philadelphus 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.
