Lavender in Minnesota

I live in Minneapolis MN, USA which is zone 4, and I want to grow a lavender hedge along the south side of my house. I need the name of a lavender that will grow fairly high (at least 75 centimeters) and will be hardy to zone four. Is there such a lavender? Do you carry it?

I am sorry, but I know of no lavender that is hardy to zone 4. The various forms of English lavender are rated as being hardy to zone 5 with Munstead and Hidcote being hardiest and surviving in the northern parts of zone 5. If you have a lot of snow they will undoubtedly make it in zone 4 as well. The problem is that the hardiest selections are also the slowest and shortest growing clones.
Your best bet would be to grow lady lavender and treat it as an annual. It is the only variety to bloom the first year from seed and should therefore fit your bill perfectly. And in mild snowy winters it will even survive for you for next year.