Flower profile
Longleaf phlox
Phlox longifolia
Longleaf phlox (Phlox longifolia) is a low shrub in the Polemoniaceae family, native in the lower 48 states, blooming mostly March–June across the U.S.
Longleaf phlox is a wildflower that USDA PLANTS lists as native in the lower 48 states. It's on our flower lists for 2 states, and across the U.S. it's most often seen in bloom in March–June.
*iNaturalist research-grade observations, as of October 17, 2026.
Quick look
Phlox longifolia, the longleaf phlox, is a species of flowering plant in the family Polemoniaceae. It is native to British Columbia and the western and west-central United States, but is absent west of the Cascades. A perennial subshrub reaching 15 in (38 cm) but usually shorter, it is typically found in dry, open situations such as slopes, rocky areas, and plains.
- It belongs to the Polemoniaceae family. iNaturalist
- USDA PLANTS describes it as an herb (forb) / a subshrub with a perennial life cycle. USDA PLANTS
- USDA PLANTS lists it as native in the lower 48 states and records it in 11 states. USDA PLANTS
- NatureServe lists it as native to Utah and Idaho. NatureServe
- In Utah, most iNaturalist sightings of it in flower come in March–May. iNaturalist
- USDA PLANTS lists its flower color as purple. USDA PLANTS
- USDA PLANTS gives its bloom period as late spring. USDA PLANTS
- USDA PLANTS lists a mature height of about 1.2 ft. USDA PLANTS
- iNaturalist has 1,622 research-grade sightings of it in Utah, ranking #23 among the 153 flowers on our Utah list. iNaturalist
- iNaturalist has 843 research-grade sightings of it in Idaho, ranking #28 among the 143 flowers on our Idaho list. iNaturalist
When does it bloom?
Conservation status
- Federal (U.S. ESA)
- Not listed No U.S. Endangered Species Act listing in the USFWS ECOS database. USFWS ECOS
- NatureServe global
- G5 Secure worldwide. NatureServe
- Utah
- No list Utah has no state law listing endangered or threatened plants, so we show NatureServe's Utah ranks instead. NatureServe: SNR, not yet ranked in Utah.
- Idaho
- No list Idaho has no state law listing endangered or threatened plants, so we show NatureServe's Idaho ranks instead. NatureServe: SNR, not yet ranked in Idaho.
- Rare elsewhere
- No other U.S. state ranks it S1, S2, SH or SX.
Checked October 17, 2026. Rankings and lists can change, so follow the links for the latest.
Can you eat it?
None of the sources we checked (NC State Extension (no page for this plant), USDA PLANTS) say whether it's edible or poisonous for people.
It isn't on the ASPCA plant list. For context only: ASPCA lists a related species, Phlox subulata (“Moss Phlox”), as non-toxic to dogs and cats. That doesn't tell us about this species, so keep pets away to be safe. ASPCA
🌿 Never eat a wild plant unless you're certain of its ID; this isn't medical advice. Worried about a person? Call Poison Control at 1-800-222-1222. Worried about a pet? Call your vet.
Where does it grow?
USDA PLANTS records longleaf phlox in 11 states.
recorded by USDA PLANTS on our state lists not recorded
See the full list of states
Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, Wyoming.
Utah counties with USDA records: Beaver, Box Elder, Cache, Carbon, Daggett, Davis, Duchesne, Emery, Garfield, Grand, Iron, Juab, Kane, Millard, Morgan, Piute, Rich, Salt Lake, San Juan, Sanpete, Sevier, Summit, Tooele, Uintah, Utah, Wasatch, Washington, Wayne, Weber.
Idaho counties with USDA records: Ada, Adams, Bannock, Bingham, Blaine, Boise, Bonneville, Butte, Caribou, Cassia, Clark, Custer, Elmore, Franklin, Fremont, Gem, Gooding, Idaho, Kootenai, Latah, Lemhi, Lincoln, Minidoka, Nez Perce, Oneida, Owyhee, Power, Twin Falls, Washington.
Growing conditions
USDA PLANTS gives Longleaf phlox a medium shade tolerance, high drought tolerance and low moisture use. It is rated for soil pH 6.5 to 8.5 and winter lows down to -13 °F.
- Shade tolerance
- Medium
- Drought tolerance
- High
- Moisture use
- Low
- Soil textures it is adapted to
- coarse, medium
- Soil pH range
- 6.5 to 8.5
- Minimum temperature tolerated
- -13 °F
- Frost-free days needed (minimum)
- 120
- Annual precipitation range
- 20 to 40 inches
- Minimum root depth
- 15 inches
- Salinity tolerance
- Low
- Fertility requirement
- Low
- Growth rate
- Slow
- Lifespan
- Long
- Active growth period
- Spring and Summer
- Fruit or seed
- Brown · Summer to Summer
- Can be propagated by
- bare root, container, seed
- Commercial availability
- No Known Source
From the USDA PLANTS characteristics data for PHLO2. USDA ratings are general guidance for the species, not a guarantee for your garden.
Names, range and relatives
Native status by region (USDA PLANTS): Canada: Native; Lower 48 states: Native.
County records: USDA PLANTS lists it in 176 counties across 11 states; the most are in Idaho (29), Utah (29), Washington (20).
Other Phlox on Bloomipedia (7): Blue phlox, Fall phlox, Prairie phlox, Spiny phlox, Mountain phlox, Santa Fe phlox, Flowery phlox.
More from the Polemoniaceae family (14 on Bloomipedia; most observed first): Scarlet gilia, Jacob's ladder, Grand collomia, Narrow-leaf mountain trumpet, Sky pilot, Flaxflowered ipomopsis, Tall jacob's-ladder.
More Utah flowers
Sources
- USDA, NRCS. PLANTS Database, profile PHLO2.
- iNaturalist, Phlox longifolia: taxonomy, research-grade observation counts and “Flowering” annotations, retrieved October 17, 2026.
- Wikipedia, Phlox longifolia (lead quoted under CC BY-SA 4.0).
- Utah: Utah noxious weed list (Utah Admin. Code R68-9-3).
- Idaho: Idaho noxious weeds (IDAPA 02.06.09, Section 220).
- USFWS, ECOS species database (ESA listing check), October 17, 2026.
- NatureServe Explorer, Phlox longifolia (global and state ranks).
- Edibility and toxicity: ASPCA.
- Photo: Daughter Dad via iNaturalist · CC BY 4.0 · resized.