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Tall Bearded Iris
Iris 'Blenheim Royal'

Family: Iridaceae (eye-rid-AY-see-ee) (Info)
Genus: Iris (EYE-ris) (Info)
Cultivar: Blenheim Royal
Hybridized by Schreiner
Registered or introduced: 1990
» View all varieties of Iris

Class:

Tall Bearded (TB)

Height:

36-48 in. (90-120 cm)

Spacing:

12-15 in. (30-38 cm)

15-18 in. (38-45 cm)

18-24 in. (45-60 cm)

Hardiness:

USDA Zone 3a: to -39.9 C (-40 F)

USDA Zone 3b: to -37.2 C (-35 F)

USDA Zone 4a: to -34.4 C (-30 F)

USDA Zone 4b: to -31.6 C (-25 F)

USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

Sun Exposure:

Full Sun

Danger:

Parts of plant are poisonous if ingested

Handling plant may cause skin irritation or allergic reaction

Bloom Color:

Medium Blue

Bloom Time:

Midseason (M)

Foliage:

Herbaceous

Other details:

Average Water Needs; Water regularly; do not overwater

Soil pH requirements:

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

7.6 to 7.8 (mildly alkaline)

Patent Information:

Non-patented

Propagation Methods:

By dividing rhizomes, tubers, corms or bulbs (including offsets)

Allow cut surface to callous over before planting

Seed Collecting:

N/A: plant does not set seed, flowers are sterile, or plants will not come true from seed

Awards (if applicable):

Honorable Mention

Award of Merit

Regional

This plant has been said to grow in the following regions:

Tuscaloosa, Alabama

Arbuckle, California

Yosemite Lakes, California

Lexington, Kentucky

Deer River, Minnesota

Isle, Minnesota

Marble Hill, Missouri (2 reports)

Weatherby, Missouri

Billings, Montana

Harlowton, Montana

Los Alamos, New Mexico

show all

Gardeners' Notes:

3
positives
1
neutral
0
negatives
RatingContent
Positive

On Jul 28, 2007, pajaritomt from Los Alamos, NM (Zone 5a) wrote:

I have been growing Blenheim Royal for some years. It has endured much mistreatment and kept right on blooming. My neighbors always ooh and aah over it. I think it is a wonderful shade of blue, developing a purple tinge in a day or so, that I find very intriguing.

Neutral

On Nov 19, 2006, Joan from Belfield, ND (Zone 4a) wrote:

Awards: Honorable Mention 1992, Award of Merit 1994

Positive

On Feb 5, 2004, rediris from Billings, MT wrote:

very prolific with several blooms on each stock.

Positive

On Oct 20, 2003, laurief from Deer River, MN (Zone 3b) wrote:

Very few tall beardeds (TBs) can survive my growing conditions. This northern MN zone 3b climate inflicts severe, extended cold during the winter months, often with little snow cover for insulation. Summer temps can exceed 90 degrees F. My soil is very heavy, compacted clay with a slightly acid pH. A large local deer population frequently tramples and sometimes grazes on my irises in early spring and late fall. Iris borers are present but managed successfully with a granular systemic grub control product. Weeds are abundant and only occasionally beaten back by an admittedly lazy gardener (yours truly). Fertilization is inconsistent, when provided at all. Most TBs here are growing with less than 6 hrs of sun per day, so growth and bloom are not what they could be under full sun condi... read more