Three main species of lavender for landscaping
Generally, the three species of lavender that you see in most gardens, cultivated at lavender farms and incorporated in commercial landscapes in the pacific northwest are the stoechas, also known as spanish lavender, the angustifolia and the intermedia. Stay with these three species, initially, for your gardening selections as you learn more about cultivating lavender.
Expressed in botanical terms, these species are presented as follows: lavandula stoechas; lavandula angustifolia and lavandula x intermedia. Lavandula may be abbreviated by l. Following these important identifiers is the variety name or patented name such as ‘grosso’, ‘super’, munstead’, ‘royal velvet’, ‘melissa’ or ‘provence’.
Each of these three species has unique growing characteristics. They visually express themselves differently in the garden and landscape. Most importantly, it is necessary to select a species that grows in your region. These three species are typical lavender species found in our growing region.
Each plant label identifying lavender should have one of these species displayed right after the genus name lavandula. The common plant variety name comprises the third entry on the label. A well organized and accurate label should properly read – lavandula x intermedia ‘grosso’; lavandula angustifolia ‘munstead’; or lavandula stoechas ‘otto quast.’ remember, the intermedia, angustifolia and stoechas (spanish) are important identifiers when determining the effects and appearance you want to achieve in your garden. In addition, if you have a special use for the fresh or dried flowers, the dried buds or the distilled oils, plant selection becomes very important.
Genuine nursery stock should contain labels that follow accepted horticulture terms; typically with nomenclature in latin. A reputable grower and seller, using industry standards, should provide a lavender plant that has a known parentage from which you can make gardening decisions. Common usage of names and descriptors such as ‘french’, ‘common’, ‘english’, ‘lavender’, ‘hidcote’ or ‘spike’ is not sufficient information and may be misleading. In addition, do not be mislead by the usage of singular variety names without the species name attached. As an example, the varieties ‘hidcote’ and ‘alba’ (white) are associated with both the intermedia and angustifolia species. There is a variety known as ‘old english’ which comes from the intermedia species.
When visiting a farm or formal lavender garden, view and contemplate the size of the plant and how it might fit in your landscape. Most plants grow to about 2-3 feet tall and at least that wide at maturity when in full bloom. It may take 2-3 growing seasons to reach a mature height. There are varieties that remain small and compact, and those that can grow to the size of large hedges for estate gardens.
Next, determine the shape and profile that you want displayed in your landscape. Lavender plants can present a bushy and informal effect (stoechas/spanish varieties), a cascading fountain effect full of concentrated color (angustifolia), or stand upright and appear stately and classic (intermedia varieties).
The stoechas/spanish varieties possess the distinctive bulb-like flower head with the perched wings. This is a popular landscape plant that produces blooms and much desired color as early as late february or early march and continues blooming during the summer and into late fall. The foliage is somewhat bushy and provides favorable ground cover. This type of lavender provides the most diversity in color selection other than pure lavender or purple. These colors include red, pink, blue, white, yellow and a combination of these colors. These varieties grow especially well on slopes, hillsides, along garden paths and at the base of concrete staircases adjoining sidewalks and common walkways. Young and tender stoechas specimens are typically the first of the three species to perish or suffer damage to sections of the plant during long cold spells. But do not be dissuaded. Healthy and established stoechas plants are generally weather-proof. For starters consider the variety, ‘otto quast’, ‘quasti’ or ‘otto quasti’. It is a signature landscape plant. It is bushy and blue and is a favorite in the wind swept community of port townsend, washington.
Holger Krisp, CC BY 3.0, via Wikimedia Commons
The angustifolia varieties provide an abundance of blooms and are described as the sweetest smelling lavender when in full bloom. The angustifolia has the distinct characteristic of resembling a fountain, flowing over with a profusion of purple, blue, or pink buds and flowers. The flower stems are thin and short in length which gives the flowers a dominant effect. The flower heads appear puffy and blunted when in bloom. As the flower heads mature, they tend to weigh down and bend the supple stalks providing the fountain effect. Angustifolia varieties bloom during late spring and early summer. They provide a second, but lighter, bloom later in the season. Angustifolia varieties are favored for their sweet and delicate lavender fragrance and versatility when used in making sachets, teas and culinary recipes. They are the species of choice for making fine perfume-quality oils.
H. Zell, CC BY-SA 3.0, via Wikimedia Commons
The intermedia varieties make a bold and dominant statement in the landscape. Certain varieties can grow quite large. They are most associated with the classic and estate gardens found in europe and on the lavender farms in the pacific northwest. The intermedia has a stately appearance with stiff and thick flower stalks reaching skyward. The flower heads at the bud stage are pointed, resembling a spear head. The intermedia produces blossoms in blue, purple and white. During dormancy and early spring, the intermedia varieties fill the garden with an abundance of a gray-green foliage texture and provide a lavender fragrance even during the winter. These varieties can provide an evergreen hedge effect in the landscape both before and after the bloom cycles. The intermedia varieties are favored sources for dried floral bouquets and for producing an abundance of flower buds and vegetative material for oil distillation. The intermedia contains in its oil make up a substance known as camphor. Camphor has a distinct but non-offensive fragrance that sets the intermedia apart from the more subtle and flowery scent of the angustifolia. All of the three species produce inviting fragrances, especially during a breezy summer afternoon.
Consultaplantas, CC BY-SA 4.0, via Wikimedia Commons
Once size, shape and color are determined, plant selection can also be made according to the shape of the leaves (thin/broad), leaf color (lime green, olive green or silver) positioning of the bud clusters on the flowering stalk (concentrated or spaced apart), and fragrance (floral, spicy, perfume or bold). Inspecting plants during most of their growth cycles will assist in your choice.
Information excerpt from Dr. Lavender's Owner's manual and is provided by the Sequim Lavender Company, Sequim, WA. All rights reserved.