What is this beautiful blue/purple flower plant?

I planted this in my garden last year. It grew to about 6 feet tall, covered with blue/purple flowers. 2 plants, each plant had 3-4 "stalks" on each plant and flowered thru the summer into October (South Carolina). Thanks for your help!
what is this beautiful blue purple flower plant, flowers, gardening, my hummingbirds loved this tall flower It grew to be 3 times this dense by end of summer
my hummingbirds loved this tall flower. It grew to be 3 times this dense by end of summer.
  24 answers
  • Meredith Black Meredith Black on Mar 24, 2014
    Looks like my Mexican Petunia.
  • Gena Crow Gena Crow on Mar 24, 2014
    I agree with Meredith Black!
  • Onie Klugh Onie Klugh on Mar 24, 2014
    Yes, it is a Mexican Petunia.
  • Linda Hopper Linda Hopper on Mar 24, 2014
    Mexican Petunia.
  • Annadee Annadee on Mar 24, 2014
    Thank you so much.... the hummingbirds went wild for these. thanks for taking time to answer. Anna
  • Melissa Martin Melissa Martin on Mar 24, 2014
    Mexican Petunia
  • Karen McLendon Karen McLendon on Mar 26, 2014
    Ruella...the tall form...looks great around mailboxes.
  • Donna Shipley Donna Shipley on Mar 26, 2014
    I thought I'd like some, but after listening to this I'm having some second thoughts... http://plants.ifas.ufl.edu/node/380
  • Louann Crum Louann Crum on Mar 26, 2014
    Mexican Petunia. I LOVE it and have this everywhere! It is a great filler, and yes, it does spread, but all the better for sharing!!!!
  • Louann Crum Louann Crum on Mar 26, 2014
    @Donna Shipley ....Don't let the article scare you off. It is great. I have had it in my gardens for years and have not issues with it. It grows in almost any condition and it is very "no worry". Try it in a small area and it you see "babies" just pull them up and share them with a friend.
    • Donna Shipley Donna Shipley on Mar 26, 2014
      @Louann Crum Thanks for the encouragement :) It's so pretty and my hummingbirds would be so happy... I'll try a little and just stay on top of it.
  • Louann Crum Louann Crum on Mar 26, 2014
    Maybe try it in a large pot...I have some like that. Started with a one plant and now I have a whole pot full. The hummers and butterflies bot love it. Good Luck!!
    • Donna Shipley Donna Shipley on Mar 27, 2014
      @Louann Crum I ordered four slips and will definitely be starting it in pots till I get a feel for it in the climate. Thank you for the suggestion :)
  • Linda Hopper Linda Hopper on Mar 26, 2014
    It's a love/hate relationship with Mexican Petunia. LOL If watered a lot it will grow tall. If not or it is in a small pot it will remain rather short. It does spread by roots but it also "throws" it's seeds when the seed pods get wet! I can't resist spraying them down when the seed pods are dry. As deaf as I am...I can hear them popping open so they can throw those seed! I have one flowerbed that I "clean to get rid of Mexican Petunias" every Spring. By Fall my flowerbed is FULL of beautiful Mexican Petunias and I love it! Oh well...
  • Donna Hehir Donna Hehir on Mar 26, 2014
    love them because of the hummingbird visits... they can be invasive in Florida... but they withstand the heat, humidity and then the drought... so....... they stay
  • Kim 'Kiewatt' Waknitz Kim 'Kiewatt' Waknitz on Mar 26, 2014
    Wondering it I could grow it in MN zone 4. If hummers like it I would love it!
  • Mel314500 Mel314500 on Mar 26, 2014
    Very invasive in Florida!
  • Betty Myers Betty Myers on Mar 26, 2014
    Live in zone 8. Not invasive here. It will multiply but you could move some plants else where or just pull them up. Mine spread a little every year which I liked because then I could start a bed somewhere else or share with friends.
  • Onie Klugh Onie Klugh on Mar 27, 2014
    I am in Kansas, it has not been invasive here. This will be my 4th year of having them. They are not supposed to even come back here but they have so far. You can break off the stems and start them in water. I do this every fall to make sure I have a plant for the next spring just in case mine don't return. I love them. You get a fresh batch of those beautiful flowers every day. They are one of my favorites.
  • Elaine Simmons Elaine Simmons on Mar 27, 2014
    Would it be too arid to grow these in the valley in AZ? My hummingbirds would love them too. I am presently watching two babies in the nest outside.
  • Kim 'Kiewatt' Waknitz Kim 'Kiewatt' Waknitz on Mar 27, 2014
    Thanks Meredith, now to find it around here. I have other zone 5 plants that do well with cover in the winter.
  • Meredith Black Meredith Black on Mar 28, 2014
    I think I'll try that with a start off mine Maybe on south side of my house.
  • Susie Susie on Apr 11, 2014
    Ruellia sp. Can be very invasive, loves moisture and will spread if it gets enough, even here in hot dry Tucson. Have seen it take over an entire bed. Just keep it cut back and under control and enjoy!
  • Sherrie S Sherrie S on Apr 20, 2014
    In Florida they can take over a bed but they are beautiful when grouped and controlled. My neighbors loved the look so I offered them all they could dig up. I showed them the area I wanted them removed from and now everything is perfect. They require no care and look nice all year long.
  • Lois Franklin Lois Franklin on May 09, 2015
    Ruella/Mexican Petunia. I got a start from my mom before she died more than 30 years ago and have dragged plants from southeast Texas, to all over Florida (Ft Myers to Jax) and back to several places in Texas! That was way before I heard they were supposed to be invasive. Planted them at my previous house nearly 20 years ago and all they did was fill out the front flower bed where I planted them. Rented out the house last year and the people completely cleaned out the once side. I nearly croaked but knew as long as some kept coming back, I'd have a start at my 'new' house. Just got to get off my rear and dig some up!
  • Elizabeth Elizabeth on May 09, 2015
    It is taking over my front yard flower beds. I am constantly trying to get it tamed.