I have grown a lot of green basil in my life. I've had less luck with purple basil until last summer, when I was able to grow several basil species, including green (genovese) and purple (amethyst I think).

This year one of my plants is green with purple spots, similar to this: http://www.seasonalwisdom.com/wp-content/uploads/2012/07/close-up-amethyst-basil-300x225.jpg

I guessed it was a mutation from cross-pollination, but a biologist friend told me that it's more likely caused by a virus, like the tulip breaking virus.

Is this common? Is the cause known?

  • 1
    The best way to figure it out is to do some grafts... put a green one on a dotted one and vice versa. You could even join two full plants in an X in the middle and see what happens. It could also be a chromosome swap. – aliential May 30 '19 at 20:37
  • Hmmm... Maybe I'll try when it grows a bit larger – raven May 31 '19 at 21:13

Your biologist friend is right, most variegated plants started out with a virused plant and growers deliberately bred from them, but in this case,it might just be a variegated Basil. Purple basil seeds do sometimes produce all green or variegated varieties - this link https://howtoculinaryherbgarden.com/types-of-basil/ suggests variegated or all green ones growing from such seeds are around 20% of the total. In many instances, variegation caused by a virus shows as yellow streaks or blotches as well as twisting and torsion of the leaves, but this is not always the case, sometimes random yellow variegation is the only symptom of infection.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.