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Daylily
Hemerocallis 'Isaac'

Family: Hemerocallidaceae (hem-er-oh-kal-id-AY-see-ee) (Info)
Genus: Hemerocallis (hem-er-oh-KAL-iss) (Info)
Cultivar: Isaac
Hybridized by Harris
Registered or introduced: 1973
» View all varieties of Daylilies

Height:

24-36 in. (60-90 cm)

Spacing:

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)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

Sun Exposure:

Full Sun

Sun to Partial Shade

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:

Unknown - Tell us

Propagation Methods:

By dividing the rootball

Bloom Time:

Early midseason (EM)

Flower Size:

Small (3" to 4.5" diameter)

Blooming Habit:

Diurnal (diu.)

Extended (ext.)

Flower Type:

Single

Bloom Color:

Bright Yellow

Color Patterns:

Self

Flower Fragrance:

No fragrance

Foliage Habit:

Dormant (dor.)

Ploidy:

Diploid

Awards (if applicable):

Honorable Mention

Regional

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

Madison, Mississippi

Grove City, Ohio

Gardeners' Notes:

2
positives
0
neutrals
0
negatives
RatingContent
Positive

On Mar 7, 2008, adbjwb from Madison, MS (Zone 8a) wrote:

Isaac is a favorite of mine. With its tiny blooms (4") on tall scapes (24-28") and smooth petals, it is an unusual Daylily. The bright yellow hints toward Chartreuse. Isaac is best displayed when planted away from traditionally shaped/colored Daylilies. It looks lovely behind shorter Daylilies with small to medium blooms in the color range of deep purple, violet or mauve (such as Fountain Tune).

Positive

On Apr 8, 2006, MLT from Grove City, OH (Zone 5b) wrote:

Loads of blooms with heavy substance, almost like plastic. Rain and sun don't change the blooms at all.