For gardeners in cold climates, successfully growing lavender outdoors hinges on selecting the right varieties that can withstand freezing temperatures and then providing them with optimal growing conditions to ensure winter survival. While lavender is known for its Mediterranean origins, several cultivars are surprisingly robust and can thrive in regions as cold as USDA Hardiness Zones 3 or 4.
The best lavender varieties for cold climates outdoors primarily belong to the English Lavender (Lavandula angustifolia) species and some specific Lavandin (Lavandula x intermedia) hybrids. These types are known for their resilience and ability to endure prolonged periods of cold and even snow.
Here are the top varieties that excel in cold outdoor environments:
1. 'Munstead' English Lavender (Lavandula angustifolia 'Munstead'):
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Hardiness: This is arguably the most celebrated and reliable cold-hardy lavender, consistently performing well in USDA Zones 4-9. With adequate snow cover acting as insulation or additional winter protection, 'Munstead' can even survive in Zone 3.
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Characteristics: It's a compact variety, typically growing 12-18 inches tall, with beautiful lavender-blue flowers. 'Munstead' is known for its strong, sweet fragrance and is also an excellent choice for culinary use. Its robust nature makes it forgiving for gardeners in challenging climates.
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Why it excels: Its inherent genetic hardiness makes it a top choice for resisting winter kill.
2. 'Hidcote' English Lavender (Lavandula angustifolia 'Hidcote'):
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Hardiness: Very similar to 'Munstead' in its cold tolerance, 'Hidcote' is reliably hardy in USDA Zones 4-9. It’s also often cited as being able to withstand Zone 3 conditions with proper care.
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Characteristics: 'Hidcote' features deeper, more intense purple flowers and a slightly more compact, upright habit, usually reaching 12-24 inches in height. It boasts an equally strong fragrance and is ideal for creating low hedges or borders.
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Why it excels: Its proven track record of winter survival in tough conditions makes it a favorite for cold-climate gardeners seeking rich color.
3. 'Phenomenal' Lavandin (Lavandula x intermedia 'Phenomenal'):
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Hardiness: Living up to its name, 'Phenomenal' is an exceptionally cold-hardy lavandin hybrid, thriving in USDA Zones 4-8. What truly sets it apart is its superior tolerance to both cold and humidity, a rare combination for lavender.
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Characteristics: This is a larger lavender, typically growing 2-3 feet tall and wide, with attractive silvery foliage and long, lavender-blue flower spikes. It's highly disease resistant.
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Why it excels: For gardeners in cold climates that also experience some summer humidity (e.g., parts of the Midwest or Northeast), 'Phenomenal' is a game-changer due to its remarkable disease resistance and cold tolerance.
4. 'Vera' English Lavender (Lavandula angustifolia 'Vera'):
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Hardiness: An heirloom English lavender variety, 'Vera' is known for its excellent cold hardiness, typically thriving down to Zone 5a, and often performing well in Zone 4.
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Characteristics: It's a slightly larger English lavender, producing abundant, sweetly scented flowers. It's a reliable, old-fashioned favorite that has proven its resilience over time.
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Why it excels: Its long-standing reputation for vigor and cold hardiness makes it a dependable choice.
5. 'Royal Velvet' English Lavender (Lavandula angustifolia 'Royal Velvet'):
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Hardiness: This variety is hardy to USDA Zone 5, and with appropriate winter protection, can often successfully overwinter in Zone 4.
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Characteristics: 'Royal Velvet' is admired for its vibrant, deep purple flowers on long, sturdy stems, making it excellent for fresh or dried bouquets. It possesses a rich, sweet floral fragrance.
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Why it excels: For those prioritizing intensely colored blooms that are also cold-hardy, 'Royal Velvet' is a strong contender.
Key Outdoor Growing Considerations for Cold Climates:
Even with the hardiest varieties, proper siting and care significantly boost survival rates:
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Exceptional Drainage: This is non-negotiable. Lavender will not survive wet, soggy soil, especially during winter freeze-thaw cycles. Amend heavy clay soils with copious amounts of coarse sand or grit, or plant in raised beds or on a slight slope.
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Full Sun: Aim for at least six to eight hours of direct sunlight daily. A sunny, south-facing location can also provide a beneficial microclimate.
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Winter Protection: Once the ground freezes, apply a layer of dry, airy mulch (like straw, evergreen boughs, or gravel) around the base of the plant to insulate roots and prevent frost heave. Avoid mulches that retain moisture. Good snow cover is also an excellent natural insulator.
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Air Circulation: Ensure good spacing between plants to allow for air flow, which helps prevent fungal issues.
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Avoid Late Fall Pruning: Do not prune lavender vigorously late in the season, as new growth is vulnerable to frost damage. Prune in early spring after the danger of hard freezes has passed.
By selecting one of these cold-hardy lavender varieties and diligently adhering to these cultivation practices, gardeners in even the chilliest climates can enjoy the enduring beauty and fragrance of lavender in their outdoor landscapes.