This particular plant, due to its fast growth and enormous spread, may be a hybrid from our earlier large herb growing operation (5000 pounds of basil a week! as an example) where we “naturally” crossed many herbs. Naturally is defined as growing thousands of plants of different varieties and then collecting and planting the resulting seed with no idea of the parentage and then selecting an unusual plant grown from such seed.
This particular plant is one plant, heavily pruned each year to keep it in bounds. Occasionally it will root from nodes, but even when it does not secondarily root, it will spread to 10 or more feet.
The flower spikes are very tall, but generally the plant is less floriferous than other lavenders such as Hidcote or Mun stead. Flowers are light blue.
The lifespan is over 20 years but uncertain how much longer. Our Mun stead and Hidcote though have survived some 40 years and are still happily growing (but not spreading significantly).