Shrubby Sundrops, Narrow-leaf Evening Primrose 'Youngii'

Kneiffia fruticosa

Family: Onagraceae (on-uh-GRAY-see-ee) (Info)
Genus: Kneiffia
Species: fruticosa (froo-tih-KOH-suh) (Info)
Cultivar: Youngii
Synonym:Oenothera fruticosa



Foliage Color:

Unknown - Tell us

Bloom Characteristics:

This plant is attractive to bees, butterflies and/or birds

Water Requirements:

Drought-tolerant; suitable for xeriscaping

Average Water Needs; Water regularly; do not overwater

Where to Grow:

Unknown - Tell us


18-24 in. (45-60 cm)


12-15 in. (30-38 cm)

15-18 in. (38-45 cm)


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


Unknown - Tell us

Bloom Color:

Bright Yellow

Bloom Time:

Mid Summer



Other details:

May be a noxious weed or invasive

Soil pH requirements:

Unknown - Tell us

Patent Information:

Unknown - Tell us

Propagation Methods:

Self-sows freely; deadhead if you do not want volunteer seedlings next season

Seed Collecting:

Unknown - Tell us


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

Waleska, Georgia

Solsberry, Indiana

Quincy, Massachusetts

East Tawas, Michigan

Omaha, Nebraska

Livingston, New Jersey

Syracuse, New York

Lewis Center, Ohio

Eugene, Oregon

Mountain Top, Pennsylvania

Mequon, Wisconsin

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Gardeners' Notes:


On Jul 5, 2014, laineygirl from Mountain Top, PA wrote:

This plant is a joy to have! In zones 5 and 6 it grows extremely well, spreading as far as you will let it. It isn't invasive here, just enthusiastic! For me, Sundrops are very easy to relocate. Simply anytime, even while it is blooming, take a shovelful, place it in a slight depression, and water well until it is established. Don't drown the plant, but be sure to not let it dry out. This is the key to successful sundrop transplantation, in my experience. Happy Gardening!


On Feb 13, 2008, mygardenefforts from Syracuse, NY wrote:

This plant is wonderful for sharing. Not too evasive here in central New York. Can be tamed with just a shovel and transplants beautifully. Very cheerful in the bed.


On Oct 29, 2006, jacobhugh from Eugene, OR wrote:

Fantastic, long-lasting flower. Plants make a dense mat which can be transplanted by the shovelful. Loves the sun and doesn't need much water here in the Pacific Northwest. A very rewarding plant in the garden.