wrapping for winter
Take a look at the link from NC State. Lavender stoechas, Spanish lavender
is not hardy and will not live through the winter. They are treated as annuals and grown as ornamentals. https://newcropsorganics.ces.ncsu.edu/herb/lavender-history-taxonomy-and-production/
Lavender just doesn't grow very well or generally for very long in Maryland. Our climate is the main problem in that they need great drainage, especially in wet or severe winters. They also do not like our humidity. They can be prone to rot rots and a fungal disease called web blight. They do well in very dry areas of the country with soil pH that is neutral to slightly alkaline.
It would be okay to experiment with a specimen or two of different varieties and cultivars. English lavender is the most popular. The best time to plant is in the spring. Here are some links from the University of Illinois, and the Lavender Assn http://extension.illinois.edu/herbs/lavender.cfm