I know this is off topic, but Indica plants readily cross here in the wild, there are 2 true forms, white and pink flowered, they cross to make pink centred and white tipped flowers (or sometimes reversed), then if the hybrid crosses with a pink (in some cases this occurs in the initial cross) they make mauve flowers.
I have crossed them myself with "pure sourced seed", e.g. some areas are isolated and only make the one colour, so I collected wild seed from these localities and started crossing.
Another interesting thing is that there are many indica physical variances, not just flower morphology, some localities are stunted, some are giant (2feet being no shock), others are slender, some heavy built, and even 3-4 generations on in cultivation they hold these traits.
I have recently sown some indica orange seed and am hoping to make a few crosses.
Now I have a question, I have white and pink flowered Spathulata, but I have never tried to cross them, would they have the same effect?