“Provence” conjures vivid images in many people’s minds: delectable food, a less frenzied pace, and beautiful scenery, not the least of which are the fields of fragrant lavender—rows upon rows of purple, pink, and white flowers swaying above silvery foliage ready for harvesting.
The National Herb Garden may not be an exact replica of Provence, but soon it, too, will have a lavender show of its own. For many years, the herb garden’s lavender collection has shared garden space with the roses in the Historic and Species Rose Garden. While this combination works aesthetically, practically, however, lavender and roses do not make good bed fellows. Roses like substantially more water than lavenders and can tolerate clay soil. Lavender, on the other hand, needs less water and excellent drainage. Roses also prefer slightly acidic soil; lavender thrives in alkaline soil. And, like many gray-leaved “Mediterranean” plants, lavender does not like humid climates. It needs drier, better circulating air than the National Herb Garden typically experiences.
Growing lavender in humid, wet conditions with less than stellar drainage is asking for trouble. One of the most common causes of lavender death is vascular wilt caused by any number of fungal diseases. Initial symptoms of an infection include wilted leaves and flower stalks. The fungi block the plant’s ability to take up water even though it may be readily available, hence the appearance of water stress in otherwise ideal conditions. The branches die back bit by bit until the whole plant succumbs. When this happens, the plant must be removed completely and destroyed.
Like many others who have struggled to keep their lavender plants healthy, the National Herb Garden has faced the same challenge. As major portions of our collection died time and again, it became apparent that we needed to try something different if we were to continue displaying this important herb. This year, we completed a major renovation of a large tract of garden space on sloped terrain along the east side of the garden. All non-woody—and a few woody—plants were removed, and the soil was heavily amended with sand and other soil nutrients. A new Belgian block border was installed to divide bed from turf, and over 50 species and cultivars of lavender were planted. The plants—many of which were graciously donated by Herb Society of America members—were propagated on site to increase the numbers for adequate display.
With greatly improved drainage, better air circulation, and the ability to control the amount of artificial watering, we might just have a fighting chance against the unforgiving Mid-Atlantic climate. The whole process took many hours of preparation and hard labor, but we’re hoping the significant initial investment will be richly rewarded in the near future. As with any new garden “experiment”, success has yet to be determined, yet we look forward to seeing how the plants fare in their new home. We encourage you to visit the National Herb Garden in the spring and determine for yourself if we have achieved a “taste of Provence.”
- For more information about the National Herb Garden:
Fields of lavender
Removal of old plant material
Propagation of material
Installation of Belgian block border
Last Updated December 10, 2008 2:43 PM
URL = http://www.usna.usda.gov/Gardens/faqs/Provence.html