Have not grown Black Aztec, Ther are some indications that it may be renamed Black Mexican, If it is, Black Mexican fits in the 85 day class, a shade earlier than its contemporary Stowell's Evergreen. Truckers favorite, both white and yellow are 90- 100 day field corns. Bloody Butcher is a field corn in the 110-120 day class.
All of these are more tolerant of cold soil than current varieties of sweet corn, so you can plant them about two weeks before your last frost date
Note that days to maturity are relative and depends on environmental conditions.

Corn needs warm soil to germinate, so I'd wait 2-4 weeks after the last frost is predicted to sow it.

Those look like very interesting corn varieties!

I found these DTM for the varieties, though only the last two are from the same seed source. Since DTM is a guesstimate anyway, maybe it's close enough.

Black Aztec/Black Mexican - 70-95 days
Trucker's Favorite - 80-100 days
Bloody Butcher - 120 days

Absent a lot of space, the best way to isolate corn varieties is to plant them so that each variety doesn't produce pollen at the same time any of your other varieties do. The recommended gap is 14 days.

Basically, that means if you want to plant three varieties of corn with DTM of 65, 80, and 95 days, you can plant them all at the same time, because they'll mature more than 14 days apart, and the pollen shed won't cross-pollinate your other varieties.

Another way to see it -- if you had three different varieties that ALL had a DTM of 70 days, you could sow them without isolating them if you sowed each variety two weeks later than the one sown earlier, say May 1, May 15, & June 1.

So you'll need to work out the arithmetic! In your shoes, I think I'd plant the Black Aztec first, wait a couple of weeks to guarantee that it pollinated before the other two and plant the other two at the same time (which we know wouldn't result in cross-pollination).

I THINK you'd avoid cross pollination on that planting schedule, but somebody may need to correct my arithmetic. I get confused when there is a date-range given, rather than one date!

Trust farmerdilla's advice on when to plant that corn. I've never grown field corn so didn't know it was that much hardier!

Thanks guys! I guess I'll try planting the Black Aztec/Mexican in a couple weeks, then plant the other two about two weeks later. It looks like I should be safe for saving seed that way!

Farmerdilla,

Thanks for clarifying about the planting date relative to frost... that explains why some say to wait and others say plant now! I've heard a bunch of names floating around for the Black Aztec corn, too. I just like that name because it sounds the most exotic and historical =) lol

Anney,

They DO look interesting, don't they? I'm hoping they taste as good as they look! Supposedly the Black Aztec can be harvested young as sweet corn, or mature for cornmeal. I can't wait to try them all!