Original Post Date 5/25/2011
In my opinion, the perfect border plant is Dwarf Mexican Petunia or Ruellia brittoniana. Although originating from Mexico and unlike the “south of the border” pun in my title, Dwarf Mexican Petunia is hardy in the United States up through Zone 8 and depending on seasonal low temps, is a tender perennial through Zone 7. You might even see it come back in Zone 6 if you mulch and protect it through winter.
Dwarf Mexican Petunia is a low growing, clumping plant with lance-shaped dark green leaves that in the summertime produces vibrant violet, pastel pink or snow white flowers depending on the variety. The greenery of Dwarf Mexican Petunia reminds me of the clean lines of typical low growing, edging plants such as liriope and mondo grass, but it has the added bonus of creating beautiful blooms! Speaking of blooms, although its flowers are tubular and very similar in shape and size to a pentunia’s, interestingly, Ruellia brittoniana is not related to the petunia family. Instead, it is of the Acanthaceae family, which oddly also includes the shrimp plant and black-eyed Susan vine.
For many years, I have had violet Dwarf Mexican Petunia planted as edging along my large flower bed in the back yard. It has been extremely dependable as a perennial in my area of Zone 8. It enjoys full sun but will tolerate part shade, although the more sun it receives the more it will bloom. Dwarf Mexican Petunia is drought tolerant and I have actually seen it referred to as a desert plant, however, all agree it does best if it receives water on a regular basis. Since making my first purchase of a few plants several years ago that I widely scattered around the perimeter of my flower bed, I have not had to make another purchase although I now have a thick, healthy continuous row of them. This is because Dwarf Mexican Petunia not only returns more vigorously every year, it dependably re-seeds and oftentimes produces, what I call, “babies” every year through rhizomes. When you find a new plant or two (or three or four) developing outside of your planting area, simply dig them up with a spade and move them to any desired spot as Dwarf Mexican Petunia transplants very well. In fact, if a bare spot develops in one of my patio planters, I usually place a Dwarf Mexican Petunia seedling in the space as it is a great blooming filler plant and its leaves drape over the sides of containers very elegantly.
As I mentioned above, after the first year of planting you will surely find new Dwarf Mexican Petunia plants growing outside of your designated area. Believe me, you will sometimes find them far from your original planting area! Late one fall afternoon several years ago, I actually witnessed the reason I find little plants growing in my sidewalk crevices, across the patio, and some, deep into the back yard. As I typically do after work, I had walked onto the patio to admire how my garden was growing (most likely with a glass of Pinot Noir) when I heard this continuous popping noise. It sounded like when you first pour milk onto your Rice Crispies cereal. The noise was incredibly puzzling to me and I was bound and determined to find its source. I suspected some odd, destructive bug had probably invaded my flower bed, but upon closer look there was no sign of any type of grasshopper, cricket or otherwise. As I leaned even closer to the soil, I was able to conclude the noise was indeed originating at ground level, but still, I could see no obvious cause. I then decided to lie down on the ground and focus intently on watching my flower bed. (I said I was determined.) As I lay there for a while, I actually witnessed a seed pod from a Dwarf Mexican Petunia pop wide open and literally spit about a dozen seeds in the air and onto the patio! What I had been hearing was the pods popping open and the seeds landing on my concrete patio. It was quite a sight and certainly reinforced to me that plants are indeed extraordinary living things and their interesting growing behaviors have purpose!
In conclusion, if you’d like to add a nice border to your beds and/or insert a little texture to your containers, I urge you to purchase a few Dwarf Mexican Petunias and give them a try. If you already have some, dig up a few “babies” that are surely sprouting up these days and share their beauty with your family and friends.
Side note: I’d like to mention there exists a non-dwarf Mexican Petunia as well. It is also a gorgeous plant that tolerates the same conditions as the dwarf variety. It is less dense in foliage and stands about 2.5 – 3 feet tall and thus, is not appropriate as a border plant. If you are specifically looking for Mexican Petunia as a nice edging plant, be sure to read the tag and note that you are purchasing the dwarf variety.
Until next time-
Update: If you wish to grow from seed, I will be happy to send some to you as I collect them this upcoming fall (Sept/Oct 2015). Please send your name and address via comment or email (I will not publish) and I’ll be happy to send some your way. They are extremely easy to grow from seed and you’ll love the results, I promise! The only thing I can’t promise is the color of the bloom as I have white mixed with blue at this “new” residence, but blue will be the dominant color.
I would love your help with dwarf Mexican petunia in getting some seeds and how to plant them?
As we spoke via email, the seeds emerge during late summer/fall but I will certainly contact you when I collect them this year. In addition, I’m looking into the seedlings we discussed. Thanks again for your interest! I think you will really enjoy the Mexican petunias.
I would love some seeds! Please email me.
As we spoke via email, the seeds emerge during late summer/fall and I have none from last year, but I will certainly contact you when I collect them this year. In addition, I’m looking into the seedlings we discussed. Thanks again for your interest! I think you will really enjoy the Mexican petunias.
I bought southern star pink mexican petunia plants today. They are just barely starting to bloom now. Will it bloom 1st year from seed? Just wondering if I should collect seed and plant outdoors in fall or late winter, since it’s a perennial do the seeds need stratification before they will germinate?
In my experience, Mexican petunia varieties indeed bloom in their first year from seed- which is a nice benefit of this perennial (zone 7b and south in US). I have found the seed to germinate very easily without stratification. The seed, once “popped” from the mother plant can be a bit difficult to see in the soil. Usually I find small seedlings emerging in the soil that alert me the seed is maturing. I then look to the center of the mounding plants for the dry, thin, elongated brown seed. Best wishes!
I would love to have some seeds for the Mexican petunias. I have looked everywhere and cannot find them
I’d love to share with you! The seed will harvest in the fall. I have a few others on the waiting list and happy to add your info to the list as well. You may respond with your mailing adress now (I will not publish your response) or I’m happy to hold onto your note of interest and touch base when the seed matures. Thank you for your interest. I think you will be pleased with the performance and beauty of these petunias!
Count me in! I would love to be added to your list for seeds. I have the non-dwarf variety in my edging bed and I love it. It’s the only plant that has successfully stood up to the sandy soil, west facing hot sun, and windy coastal climate. TY!
Thank you for reading my blog and so sorry for the delay in responding. I’ve had a family emergency and haven’t written or checked online here in a bit. Please email your mailing address to me at [email protected] and I will be happy to share. I don’t expect to harvest for about a 2-4 weeks yet. Best, Cindy
If you harvest dwarf Mexican petunia seeds this year, I would love to have a bunch of them. Purple or blue is my favorite, but a mix would be fine too.
Please E-mail me
Hello! I am in Texas and the seeds haven’t yet popped – probably because we have had 3 times the rain we usually have and they just haven’t dried up enough, but I am looking out for them daily. I am happy to share what I harvest. Please send your mailing address to me at [email protected]. I expect the seeds to become hard for harvest within the next month. Thank you and sorry for the delay – we’ve had a family medical emergency. -And, thanks for reading my blog!
I have all 3 colors in my garden (dwarf form and non-dwarf)
It is hard to find seeds for violet non-dwarf so I just propagate them using cuttings.
Recently I just realize their seeds will become sticky once it is exposed to water and stick to your hand.
I think this is another way how they spread their coverage.
Thank you for this valuable information. I have not grown the non-dwarf type but I’ve seen them planted in commercial landscapes en masses and they are beautiful. I appreciate (and I’m sure do my readers) knowing they take well from cuttings!
I would love some seeds… I cannot find the blue/purple version anywhere and would love these as a border.
Hello and sorry for the delay in responding. Please send me your address to [email protected]. I plan to harvest seed in the next couple of weeks and will be happy to share! Cindy
If the offer still stands, I would be delighted to receive done seeds from you for the dwarf Mexican petunias. I have several of the non-dwarf in my yard as shrubbery and those are gorgeous. I’d love some of these dwarf plants as a sidewalk border for my front lawn. 🙂
Hello. My blog site is a mess right now and I’m sorry if I missed your comment. I just collected seed and will be happy to share them. If you haven’t already, please email me at [email protected] with your address and I’ll send the seed! Thanks, Cindy