Oenothera biennis can get to be very tall, as well as Oenothera hookerii

Here is a link that might be useful: Oenothera biennis

The common widespread evening primrose with large conspicuous flowers is showy evening primrose (O. glazioviana syn. O. erythrosepala). It can be identified by its having reddish glandular hairs and larger, more impressive flowers than O. biennis.

There are several species of "tall" Oenothera.

Oenothera biennis is a Eastern NA native and a nice biennial weed.

O. elata hookeri is beautiful but I'm not sure it's hardy for zone 6.

O. fruticosa has dozens of cultivars, all nice and a bit assertive.

O. glazoviana is one of my favorites.

Good retail garden centers in your area would carry one or more of these. Otherwise, they're available (especially the superior hybrids and cultivars) through several mail-order companies.

Joe