Have purchased your Crambe maritima seed packets, and have now also ordered seed from Ireland (hope they arrive), bountiful gardens, and two other places. Hopefully getting them from multiple sources will provide the genetic diversity needed to find one or two plants that will thrive in my zone 7 yard here in TN. looking forward to working with this crop. 
Great! Come back and let us know how they all perform for you.
We will have a number of new sea kale additions this fall, so if you want more diversity, we’ll have it. We’ll also be offering more Crambe tatarica, which is similar to sea kale, but more tolerant of hot summers.
Sounds good, can’t wait.