How to Grow and Care for Mexican Petunias (Ruellia Simplex)

Beloved by many gardeners for its heat tolerance and shade-loving nature, but reviled by others for its eagerness to spread with abandon, R. simplex can be divisive.

Thanks to its sweet purple flowers, however, we come down firmly on the pro-ruellia side of the debate.

With forms tall and short, this evergreen, herbaceous perennial – suitable for growers in USDA Hardiness Zones 8 to 11 – deserves consideration for inclusion in southern gardens.

The tall version forms clumps 18 inches across, while the short type forms 12-inch clumps.

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It’s an erect, often-multi-stemmed plant with dark green, droopy, slender, and long leaves.

It’s especially loved for its papery, trumpet-shaped flowers that mimic every shade of the purple rainbow, as well as white and pink.

Sadly, each lovely flower lasts just a day. But fret not – the plant produces a succession of profuse two-inch flowers daily from spring through fall.

Let’s learn more about this lovely but divisive plant, and why Floridians want nothing to do with it! Here’s what we’ll tackle in this article:

If you live in Florida, you’re certainly excused from reading this article, though you might want to check below for a cultivar that is safe to grow in your region.

Or perhaps you’d like to learn about growing turmeric, which also does quite well in the Sunshine State.

Interestingly, the stem of this plant becomes more purple when it’s in bright light, as opposed to when it’s grown in a shady area, where the stem stays fairly green.

I’ve always used my Mexican petunia as a shade plant