Q. I'm interested in growing a few lavender plants. I want the variety with the wonderful fragrance that is harvested to make sachets. Can you please advise me?
- ---Josie "in NJ near Cherry Hill and Pennsauken"
- ---Melanie in Kingsport, TN
"The designations French, English and Spanish are not botanical reference points", she warns, urging gardeners to select the perfect variety for their climate and intended use by botanical name. It may take a bit more time—especially when your favorite catalog or grower just lists a 'country name'—but it's the only way to get the exact type you need and want.
Time for a little botany then. The genus name for all lavenders is "Lavandula".
The most common species is angustifolia (which means 'narrow-leaved'); it may also go by the species name officinalis (because it's the 'official' lavender. It's 'country name' is 'English' (at least when the namer gets it right), and it's also known as true lavender. Ellen explains that all of the varieties in this species have the sweet fragrance that many growers seek, and the plants are quick to bloom, often producing flowers their second year—even when started from seed. These are also the most cold-hardy varieties, surviving winter nicely in Zone 6, and often in Zone 5.
Ellen describes twenty different named varieties of this species in her book, and they showcase a dazzlingly diverse array of attributes—heights from seven inches to three feet, with flower colors in white, pink, blue and grey as well as the familiar light purplish/violet hue. Different varieties have different bloom times, and some can even bloom more than once a season if the first run of flowers is promptly removed. (So buy the book if you want to be serious about this; you'll be able to choose the perfect varieties.)
So-called 'Spanish lavender' is generally the stoecas ('stoi-kas') species, but a plant labeled 'French lavender' could be either the stoecas or dentana species. Either way, these are true 'Mediterranean' plants that do best in areas warmer than Zone 6.
And there are many other species. Latifolia, or 'spike lavender', is tall, with broad leaves and bright blue flowers—but Ellen warns that the blooms smell like camphor instead of lavender! Just as winter hardy as the 'English' types, a cross known as intermedia is recommended for areas with high humidity, and for the best dried flowers, but it can't be grown from seed—you have to start with cuttings. Ellen describes ten different varieties of this species, highly praising the fragrance of several, including the well-known "Provence". (And yes, this means that despite its variety name, Provence is NOT a 'French lavender!')
Many types of lavender can be grown from seed, but the plants cross pollinate so readily, it's hard for growers to be sure that the seeds in any given packet will produce the exact plants you want. This isn't the seed producers fault—the plants are just really frisky in the field. Nursery starts are more reliable for getting an exact variety, and cuttings taken from a fellow gardener's lavender will always produce the exact same plant.
The biggest requirements for any lavender are full sun and excellent drainage. Not 'good drainage'; excellent drainage! Planting in heavy clay, compacted soil or areas that drain poorly will kill the plants. So if you don't have naturally loose soil, lighten up the area with lots of perlite, soil-free mix or sand before planting. Lavender also prefers its soil on the alkaline side, so if your earth is acidic, use lime or wood ash to get the pH up between 7 and 8. Don't worry about feeding, a little compost once a year is all the plants will need.
To avoid the overgrown, woody look that many lavenders develop, give the plants a nice light pruning every Spring—about two weeks after all threat of frost is gone (right around the same time you should prune your roses). This will keep the plants tidy and productive.
…And alive; Ellen warns that old plants that are heavily pruned after years of neglect often join The Choir Invisible. One option in such circumstances is to tear up the old lavender and replant a fresh batch; many growers do this every five years or so just to keep the plants vigorous. (And it allows you to choose a variety that might be better suited to the space.) Otherwise, Ellen suggests pruning one-third of an overgrown plant back heavily each spring over a three year stretch to get it back into shape without killing it—always an admirable horticultural goal!