Both Hidcote and Munstead are great for bees, and pretty tough for a sun-loving plant. Lavandula angustifolia is the 'true' lavendar, and both Hidcote and Munstead are hybrids of this, so there's no need to worry about trying to buy it specifically. Hidcote is a bigger plant, Munstead more compact, but both will attract bees and butterflies. Maybe not as much as catmint, though, which is much tougher and more long-lived, but without that lovely fragrance. Nepeta 'Six Hills Giant' is a superb hedging plant if you want something that will live longer than short-lived lavendar but look quite similar. Just a suggestion.
