'French' lavender, scientifically known as Lavandula dentata, is a distinct species within the lavender genus that offers a different set of characteristics compared to the more commonly known English lavenders (L. angustifolia) and lavandins (L. x intermedia). While it has a noticeable fragrance, its unique appearance and scent profile set it apart.
Here are the defining characteristics of 'French' lavender (Lavandula dentata):
1. Distinctive Foliage: Toothed and Silvery-Green:
-
"Dentata" Means Toothed: The most striking feature of Lavandula dentata is its foliage. The specific epithet "dentata" is Latin for "toothed," referring to the finely serrated or fringed margins of its leaves. This sets it apart from the smooth-edged leaves of most other lavenders.
-
Color and Texture: The leaves are typically gray-green or silvery-green and often have a slightly woolly or fuzzy texture, especially when young. This combination of toothed edges and a soft, silvery appearance makes it highly ornamental even when not in bloom.
-
Highly Aromatic: The foliage itself is very aromatic, releasing a strong scent when touched or brushed.
2. Unique Scent Profile: Herbaceous, Camphoraceous, and Rosemary-like:
-
Less Sweet, More Pungent: While it undeniably smells like lavender, the scent of L. dentata is less sweet and floral than English lavender (L. angustifolia) and often more herbaceous, camphoraceous, and sometimes described as having notes of eucalyptus or even rosemary. Its essential oil typically contains high levels of 1,8-cineole and camphor, but very low levels of linalyl acetate.
-
No Culinary Use (Generally): Due to its higher camphor content and different aromatic balance, L. dentata is generally not recommended for culinary use. Its flavor can be quite bitter or "soapy."
-
Confusion with L. stoechas: It's important to note that Lavandula dentata is one of several species colloquially called "French Lavender." Another common species referred to as "French Lavender" is Lavandula stoechas (Spanish Lavender), which has a more resinous, piney, and sometimes "pineapple-like" scent due to very high camphor levels and distinctive "bunny ear" bracts. L. dentata has a different appearance and a slightly less overwhelmingly camphoraceous scent than L. stoechas.
3. Flower Appearance: Pale Purple Spikes with Bracts (sometimes):
-
Color: Flowers are typically a pale to medium lavender-purple or blue.
-
Spikes: It produces dense, somewhat short flower spikes on long, slender stalks that rise above the foliage. The flower head itself is often compact and cylindrical.
-
Bracts: While not as prominent as the large "bunny ear" bracts of L. stoechas, some forms of L. dentata can have small, leafy bracts at the top of the flower spikes.
4. Growth Habit: Bushy and Medium-Sized:
-
Size: Lavandula dentata typically grows into a bushy, semi-woody perennial shrub reaching 2-3 feet (60-90 cm) in height and spread, though some sources list it up to 4-5 feet wide.
-
Mounded Form: It forms a pleasingly rounded, dense mound.
5. Extended Bloom Season and Warm Climate Preference:
-
Long Bloom Time: One of its most appealing features is its exceptionally long blooming season. In mild climates (USDA Zones 8-11), it can bloom almost year-round, often peaking in late spring/early summer and again in fall/early winter. In cooler climates with frost, it will still have a very long bloom period from spring through fall.
-
Heat and Humidity Tolerance: Unlike English lavenders, L. dentata is notably more tolerant of heat and humidity, making it a good choice for warmer, more humid regions where other lavenders might struggle with fungal diseases.
-
Hardiness: It is less cold-hardy than English lavenders and lavandins, generally hardy in USDA Zones 8-11. It's not frost-tolerant and will require protection or be grown as an annual in colder zones, including much of Door County WI or areas with similar climates.
6. Growing Conditions and Uses:
-
Full Sun and Well-Drained Soil: Like all lavenders, it requires full sun (6-8+ hours daily) and extremely well-drained, lean, sandy, or gravelly soil. It is highly susceptible to root rot in wet conditions.
-
Drought Tolerant: Once established, it's very drought-tolerant.
-
Ornamental Value: Primarily grown for its highly ornamental, attractive foliage and long bloom season. It's excellent for Mediterranean gardens, rock gardens, containers, and borders.
-
Crafting/Aromatics: Its dried flowers and aromatic foliage are used in sachets, potpourri, and essential oils for non-culinary applications like soaps, lotions, and perfumes where its distinct scent profile is desired.
-
Pest Resistance: Deer and rabbits generally avoid it.
In summary, 'French' lavender (Lavandula dentata) is defined by its unique toothed, silvery-gray foliage, an extended blooming season, and an herbaceous, camphoraceous, rosemary-like scent. It's more tolerant of heat and humidity than its English counterparts but less cold-hardy, making it a valuable, distinct choice for ornamental gardening and specific aromatic uses, often found at specialized lavender farm operations or when you buy lavender online from retailers like islandlavender.com.