SUBGENUS: PENSTEMON

Section: Coerulei

Typified by its blue-green or grey-green, leathery foliage. Leaves are attractive all year, many turning a stunning pink-red through the winter. Flowers are on spikes and on stout stems. Pastel colors. Very drought tolerant. Like alkaline soil –sand, gravel or clay. Found on the Great Plains, Great Basin and Rocky Mountains.

Key

Species: light blue cell =popular parenthesis = not reported in cultivation Also in cell: plant height when in bloom EASY =easy to grow color(s) of flower

Cultivation characteristics: size of flowervery large= >1 ½ “ large=1-1 3/8” medium= ½ - 1” small= < ½ “

general description site suggestion= rock garden, trough, dryland garden, border

Cultivation needs: information primarily from USDA website: or

Amount of sun exposure: ☼ full sun **protect from winter sun: pine boughs, or north exposure by rock ½ = half day sun T=tolerates shade

Soil, moisture, sun recommendations for cultivation

Species / Bloom
Season / Cultivation
Characteristics / Cultivation Needs / Elevation and Habitat / Distribution / Reported cold hardiness in cultivation
Soil / Moisture / Sun
acuminatus
8-18”
purple-blue / April-May / medium flower / sandy, gravelly
Must have perfect drainage.
pH 6.0-8.0
adapted only to coarse-textured soil / xeric
12-30” precipitation tolerance / ☼
shade intol. / 2,100-4,600’
sandy areas / se. WA, adjacent ID, nw. NV, e. OR
herbaceous; popular, sturdy, good color; early bloomer; as wide as tall; occur singly or in clumps; moderate lifespan; root depth 14”
Cultivated in: OR, WA, MT, NY
angustifolius
1’
variants of blue / April-June / medium flower / sandy, gravelly; neutral to alkaline; good drainage;
Adapted to coarse, medium and fine textured soils; pH Minimum 7.0-Maximum 8.5; does poorly and short-lived in heavy soils / xeric
9-35” precipitation tolerance / ☼
shade intol. / 3,900-7,500’
Great Plains, other sandy , dry plains / NM, CO, AZ, MT, ND, UT, ND, SD / -20°F
subshrub; 3 yr longevity; transplant early; one to several stems; much variation among varieties; root depth 6”; extremely sensitive to root rot fungi and if over-watered the entire stand will be destroyed.
Although not necessary, narrow leaf penstemon responds well to fertilization. After establishment, it does not appear to be damaged by the use of pre-emergent herbicides.;provides a food source to small birds and mammals. It is heavily used by hummingbirds and various insects during flowering.
dryland garden
Cultivated in: GB, NY, MI, WI, MN, RockyMt. region
arenicola
7”
bright blue / April-June / small flower / in east: sand and gravel beds / xeric
needs a dry location / ☼ / 5,900-7,400’
dry, sandy hills, plains and white shale bluffs in sagebrush communities / sw. WY (RedDesert), UT, CO / -20°F
compact; well liked; showy; several stems
dryland garden, rock garden, troughs
does well in RockyMt. region, NM, e. WA; east coast in sand and gravel beds
bracteatus[threatened] / June / medium flower / xeric / ☼ / sc. UT / to 0 º F
desirable; blooms 3rd year
rock gardens;
Cultivated in: se. WA
buckleyi
18-36”
pink, pale blue, lavender / April-May / medium flower / xeric / ☼ / 3,500-6,000’
sandy soils / Great PlainsKS to TX
long lived; pleasing; can be striking
dryland garden
Cultivated in: many places from NE to CA
carnosus
6-14”
lavender-pink to blue-violet / May-July / medium flower / xeric / ☼ / 4,900-8,500’ / c. and ne. UT / -20°F
may be long lived in some sites
Cultivated in: Denver
cyathophorus
many colors
18” / early / medium flower / xeric / ☼ / dry, rocky sagebrush; clay loam soils / nc. CO, WY
profuse bloomer
Cultivated in:
fendleri
2’
violet / early / medium flower / xeric / ☼ / sandy soils / TX, NM, OK, KS
Cultivated in: CA to Midwest
(flowersii)
12”
pink
[rare endangered] / unknown / medium flower / NA / NA / NA / clay badlands / UT / NA
grandiflorus
36”
light pink-lavender / very large flower / gravelly, sandy, dry location.; acid, neutral or alkaline soils; requires well-drained soils; grows well when planted in open dry situations,. / xeric / ☼
tolerates
semi-shade / Great Plains / e. MT, WY, M to TX / -20ºF
Spectacular; robust single stalks of smooth, clasping leaves; showy; one of the biggest and the most easterly members of the Coerulei section;sometimes monocarpic, but often produces sidesets or reseeds;
dryland garden
Cultivated in: widely cultivated
harringtonii
12-28”
pink-lavender / June / medium flower / xeric / ☼ / 7,200-8,000’
mountains / only in CO (Vail area)
haydenii[rare & endangered]
20”
lavender / May-June / very large flower / NA / NA / NA / sandy hills / NE, WY / very hardy
hardy; was widely grown; may no longer be cultivated; sprawling to upright
NA
NA
immanifestus
2 ½ ‘
lavender-pink / May-June / medium flower / xeric / ☼ / 4,900-6,500 / Great Basin desert, w. UT, e. NV
robust, stocky; not widely cultivated
dryland garden
Cultivated in: NV, WA, MI, NM, CO
lentus
8-16”
deep rose to red-violet / May-June / medium flower / xeric / ☼ / sandy, gravelly / Four Corners
long lived; popular and pleasing
dryland gardens
nitidus
6-8”
aquamarine / April-May / medium flower / adequate moisture during bloom; then dry / ☼ / 3,500
clay and gravelly soil; plains, prairies / se. BC, s. Alb, w. Man, MT, ND, SC, n. WY / -20ºF
beautiful, should be magnificent, small, roundish-leaf beauty with 6 to 8 inch spikes of aquamarine blue;almost succulent , ever-blue rosettes. One of the best; self-seeds but not in excess
large rock garden, raised bed; dryland garden
Cultivated in: many areas of U.S.
(osterhoutii)
28”
blue to lavender / June / medium flower / NA / NA / 5,500-7,200’
sagebrush slopes / nw. CO, UT
pachyphyllus
12-20”
lavender, blue, purple
EASY / May-June / medium flower / xeric / ☼ / 4,500-10,500’
dryland, gravelly or sandy soil / Grand Canyon, , UT, CO, NV, WY / -20ºF
showy; lives 3-4 years; waxy, succulent rosettes showy in their own right. Tall spires of lavender flowers ; Under irrigation, fusarium wilt can be a problem.Flowering should not be expected until at least the second growing season.
dryland garden
Cultivated in: widely
secundiflorus
14”
orchid pink
EASY / May-June / large flower / sand beds if out of range / xeric / ☼ / 5,4000-9,000’
eastern plains, foothills; gravelly, sandy soil / WY , CO, NM / -20ºF
long lived, flared tubular flowers on one side of stalks with broad blue-gray leaves. Xeric
dryland garden
Cultivated in: native range, MN, MI, ME
versicolor
10-14”
sky blue to blue-lavender
EASY / May-June / xeric / ☼ / 5,000-8,000
river valley / sc. CO (ArkRiverValley) / -20ºF
long lived; popular; one to a few stems; beautiful
dryland garden

* parenthesis=not reported in cultivation

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