I whole heartedly recommend letting those soils and amendments settle and become one media for at least a couple days after mixing before planting. have you checked the extended weather forcast? Lots o cold rain coming your way towards the end of April. Something to think about. I guarantee...
Phosphorous deficiency, probably an active transport, you can see it a little bit on some of the other leaves as well. Its nothing too scary, but there are numerous causes, potassium in the next watering usually helps, especially if it accompanied by a little phosphorous. could also be simply...
JTR reveggin cuz of sudden hormonal swing.
Its the genetics. mutated of course do to some odd reason (the seed that is). glad your doin good... missed seein yah.