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Woody > Pinus > Pinus strobus > Pinus strobus 'Sea Urchin'

Pinus strobus

'Sea Urchin'

Sea Urchin White Pine

Origin:  It was discovered as a seedling in low mounds of Vermont by Sydney Waxman of the University of Connecticut.
            Mike's Opinion

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One of the finest selections of species known as Pinus strobus 'Sea Urchin' is an excellent, slow-growing, fuzzy-looking, dwarf conifer that is perfect for small gardens or containers. This species of strobus is more blue in colour and contains long, thin needles that contribute to its soft, globular appearance. It is generally less than 90 cm in height and is very attractive to bees, butterflies, birds and other small mammals. These attributes make it an excellent addition to rock gardens and as a specimen plant in home gardens.

Michael Pascoe, NDP., ODH., CLT., MSc. (Plant Conservation)


'Sea Urchin'
Shrub (evergreen)
USDA Hardiness Zone
3a - 9b
Canadian Hardiness Zone
3 - 8
Temperature (°C)
-39.9 -(-3.8)
Temperature (°F)
-40 - 25
60 - 90 cm
60 - 90 cm
Description and Growing Information
Flowering Period
General Description
A multi-stemmed dwarf evergreen shrub with a thick, rounded pattern of growth complemented with silver-blue foliage. It is extremely compact and slow growing. It is an excellent addition to home gardens or rock gardens for its form, texture and color detail.
Works as an accent in rock gardens or small home gardens. This plant can be used in general garden use, mass plantings, hedging and screening as well as rock and alpine gardens. Its colour, texture and form sets it apart from other landscape plants with less refined foliage.
Thrives in organically rich, medium moist, well-drained loams in fully lit to partly shaded conditions. The soil must be acidic to mildly acidic or neutral (pH 5.6-7.5) for this plant to grow.
A compacted spreading form that has a globular appearance with a flattened top.
ID Characteristic
The blue-green and silver Sea Urchin White Pine can grow to a mature height of 90 cm tall and 90 cm wide. If grown under ideal conditions, this species can be expected to live past 50 years. The slow growing shrub requires and appreciates partial to full sun and partly moist soil. This plant will not tolerate standing water. This white pine prefers acidic loam soils and is subject to chlorosis (yellowing of the needles) if the soil is alkaline. A relatively sheltered area is required in order for this plant to benefit and grow. Because this shrub is a slow growing only some maintenance and upkeep is required. Trimming back the new growth of the present season is what is recommended.
Blights and a bark condition called white pine blister rust are the most common diseases associated with this plant and may cause complications or death. Cankers and insects can also negatively affect the plant. The insects include white pine weevil, bark beetles, white pine shoot borer, Zimmerman moth larvae, pine sawfly, scale, spider mites and aphids. Some small animals can consume parts of the plant such as deer and rabbits.
Horticultural origin.
Bark/Stem Description
Young bark is often light green. Once mature, the bark turns silver and starts to crack and form scales. Heavy resin is often deposited where branches have been removed or broken.
Flower/Leaf Bud Description
Its buds elongate, causing it to grow slightly. Its protective scales vary from yellow-orange to brown in colour.
Leaf Description
Aromatic, long, less refined pine needles.
Flower Description
It is a monoecious species. Male flowers are found in clusters of cylindrical, small, yellow flowers at the branch tips. Females contain light green flowers that are shaded red located at the end of the branches as well.
Fruit Description
It is a rarity to see cones present on this species. Although, when they are present, they show in the fall. They appear slender and long (1-3 inches), broad when opened, and have scales with a rounded and slightly bent tip.
Colour Description
The silver finished needles vary in colour from a yellow-green to a pale green-blue.
Texture Description
Appears soft with a relatively fine texture. Well known for it’s unique feel and look in the landscape.
Notable Specimens
Whistling Gardens, Wilsonville, Ontario, Canada.
Can be propagated by grafting but is more commonly grown from seed. Seeds can be directly sowed outdoors in the fall and in vented containers, coldframes or unheated greenhouses in the winter. Propagation is possible indoors as well. Seedheads are bagged, removed and collected once the seeds are dry.
Bloom, Adrian, and Richard Bloom. Gardening with Conifers. Willowdale, Ont.: Firefly, 2002. Print. Bitner, Richard L. Designing with Conifers: The Best Choices for Year-round Interest in Your Garden. Portland, Or.: Timber, 2011. Print.