You are free to disagree all you want but it doesn't change the facts. Lythrum salicaria is one of the top 10 invasive species in both this country and Canada. It is listed as an invasive species in 47 of the 48 contiguous states and in all the bordering Canadian provinces. It is also illegal to grow, sell or distribute the species and any garden cultivars of the species in 17 states. It is not that it 'could escape' or 'could pollinate' - it does, and that fact has been well established. They are all the same plant - it's just that selections were made for garden cultivation with the assumption that the seeds they produced were sterile. This has been determined to be false. Garden cultivars are just as likely to produce fertile seeds as their wild cousin and the seeds will not necessarily come true to form. In other words, they can revert. And that fact is behind the prohibition of any named cultivars in states that restrict or prohibit sales. One of the issues that always seems to stir up discontent about the validity of invasive species is that it is often not obvious in a garden setting that they are invasive so the assumption is made they are not. This is a fallacious assumption. Each plant of Lythrum can produce as much as 2.7 million tiny seeds which are easily dispersed by wind and water. They can travel great distances, land on moist soil, overwinter and then germinate. As they prefer moist/wet conditions, infestations disrupt wetlands and waterways and alter ecological conditions, overwhelming native plantings and altering habitat and food sources for wildlife. Forget-me-nots and orange daylilies are not considered invasive because they do not cause ecological or economic harm, which is a major factor in the definition of an invasive species and is the criteria purple loosestrife meets with open arms. Annual control costs, loss of habitat and disruption of agricultural crops run into the millions of dollars. Vinca and English ivy are considered invasive in some areas and certain regulations apply to them as well. There are so any other great garden plants that pose no threat to the environment that it just doesn't make sense nor is it very responsible to persist in growing what is one of the most significantly invasive plant species we have to deal with.

link IDd as an invasive Lythrum salicaria (purple loosestrife). .. in the perennial forum ken

That's a pretty good guess and would certainly provide a similar effect.

Thank you for helping identify this plant. The information I am finding online for the Epiphyllum oxypetalum makes for good reading. I am a bit concerned it may be too large and require some elaborate support system which will represent a challenge when moving it. I really hope it flowers some time because the flowers look awesome!