Leucanthemum x superbum 'Alaska'
Updated: Nov 7, 2021
I used to grow this with great success while living in Sonoma County just seven miles inland from the Pacific Ocean. The location had perfect soil, alluvial with a high fresh water table; cultivating it could not go wrong. That all changed when we moved to Silicon Valley, yet I still insist on growing it.
The soil here has great drainage, minimal clay, and rocky but difficult to retain water. Over the course of a few years, we have been adding compost and mulch to the soil, and it appears to be paying off with healthy plants for the first time this year. I look forward to the reward of long lasting blooms!
Through this winter, the Leucanthemum has kept its foliage, giving the garden something to look at while other plants still need to emerge from their winter slumber. This particular cultivar, 'Alaska', is the tallest reaching over 4' when in bloom. The video below illustrates what happens when they become large...mostly remaining upright but still some floppiness. Several references discuss its drought tolerance, but I have observed wilt when dryness is combined with warm weather. A well composted soil and even moisture appears to be the best solution.
This video helps to illustrate their floppiness, but they can still hold more flowers upright.
Botanical Name: Leucanthemum x superbum 'Alaska'
Superbum: Meaning very early, probably in reference to its bloom period
Common Name: Shasta Daisy
Family Name: Asteraceae
Origin: Despite the name, not native -
Leucanthemum × superbum, commonly called Shasta daisy, is a hybrid developed by Luther Burbank (1849-1926) in the 1890s near snow covered Mt. Shasta in northern California. Burbank crossed L. vulgare (European oxeye daisy), L. maximum (Pyrenees chrysanthemum), L. lacustre (Portuguese field daisy) and Nipponanthemum nipponicum (Japanese field daisy) to produce Leucanthemum × superbum which was given the common name of Shasta daisy. This hybrid typically grows to 2-3' tall with a spread to 18" wide.
~ As referenced from the Missouri Botanical Garden
Positioning: Middle ground
Garden Themes: Cottage, cutting, coastal, butterflies, meadow
Uses: Floriculture, border, mass, containers (may prefer smaller cultivar)
Type: Evergreen, semi-evergreen herbaceous perennial
Form: Clump, erect
Size: 4 tall when in bloom and 2' wide
Outstanding Feature(s): Flower
Shape: Lanceolate, oblanceolate
Color: Dark green
Flower: Spring to Summer. Showy, daisy-like white rays surround yellow disk.
Fruit: Unclear at time of posting if this cross produces seed.
cultural requirements, tolerances & problems
Sunset Zones: A1-A3; 1-24; H1
USDA Zones: 4-9
Light: Full sun to partial shade
WUCOLS SF Bay Area Hydro Zone: Moderate
Texture: Sand, loam, clay, well composted
Moisture Retention: Well-drained; does not tolerant combined heat and dryness
Tolerances: Brief periods of drought
Problems: May flop over when in peak bloom. Provide support.
Branch Strength: N/A
Insects: Aphids, leaf minors, spider mites
Disease: Verticillium, leaf spot, stem rot
citations & attributions
Bayton, R. (2019). The Royal Horticultural Society's the Gardener's Botanical: An Encyclopedia of Latin Plant Names. London: Mitchell Beazley.
Norris Brenzel, K. (Ed.). (2012). The New Sunset Western Garden Book. New York: Time Home Entertainment, Inc.
NC State Extension. "Leucanthemum x superbum." North Carolina State University, Raleigh. Accessed on November 6, 2021, from https://plants.ces.ncsu.edu/plants/leucanthemum-x-superbum/.
Plant Finder. "Leucanthemum x superbum 'Alaska'. Missouri Botanical Garden, St. Louis. Accessed on November 6, 2021, from https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=244690&isprofile=0&.
Water Use Classification of Landscape Species. "WUCOLS IV Plant List." University of California, Division of Agriculture and Natural Resources, Davis. Accessed on November 6, 2021, from https://ucanr.edu/sites/WUCOLS/Download_WUCOLS_IV_List/.
Feature flower purchased from Shutterstock.
All other photos by TELCS.