|I have a Trumpet Vine growing on a trellis, on a deck, on the south side of my house. I've had the plant for three years and it has yet to flower. It freezes to the ground every winter and takes off again in spring. I tends to like to grow on the inside of the trellis in the shade (I have it planted in the sun but it constantly grows inward). I've talked to numerous people, nurseries, extension agents etc..., and they all say the same thing. They have heard of this problem before, here in Minnesota, but don't know what causes this problem. I've heard everything from "the flowers grow on second year wood" to " it needs more fertilizer". The vine tends to grow very vigorously and appears to get bigger every year. PLEASE don't tell me that this is a very easy vine to grow.|
|Well, I don't have the magic pill but I can give you some "points to ponder". You have probably heard a lot of what I have to say. Trumpet vine takes a very long time to flower in most every case. I have personal experience and "I feelyour pain", you'll never hear from me "it's an easy vine to grow". I have several, and some flowered after 3-4 years, one I think is 7 years old and hasn't flowered.
Trumpet vine flowers occur on new growth (as opposed to flowering on old wood). I would suspect that the plants are busy building up reserves in their root systems to enable flowering. Also, you could be on the edge of their hardiness range and they may not have a long enough growing season to put out flowers. How soon does it freeze and die back to the ground each year? Most flowering plants need a given amount of "warm hours" in ratio to "cold hours" annually to perform as they are supposed to.
Really all I can suggest is that you pamper them through the winter, especially before you get your big snows, and they should flower as the plant ages and matures. As you have already heard, provide lots of organic material such as compost, fertilize regularly with a 5-10-10, and, I wouldalso check the soil. Most vines like a well drained, fertile soil. You could have a soil deficiency that is causing the whole problem. Check with your local extension agent (ph# 612-682-7394) about having a soil test performed. Other than that...I am getting ready to dig up the 7 year old trumpet vine in my yard.