I believe you have a taxonomic error on your website. Last year I purchased Mimosa Tree from you, among a couple >hundred other species of plant. On your website you list this as Albizia julibrissin – which, anywhere else, is classified as >Persian Silk Tree. As for Mimosa Tree itself, this is classified elsewhere as Mimosa tenuiflora. Just what is it that you are >sending out when you sell Mimosa Tree? Is it Albizia julibrissin or Mimosas tenuiflora? More confusing still, you description of YOUR Mimosa Tree does not match the properties ascribed to Albizia julibrissin elsewhere. This is very >important that I get an answer because whereas one type thrives in Zone 9+ or higher; the other can thrive in Zones 6-9. >Big difference... particularly in light of where I am growing.
Common names such as "Mimosa Tree" are notoriously unreliable. There are countless plants that have multiple common names (some have dozens!) that are shared with other species. For identification purposes, the botanical names are more reliable (but not always, and that's another story!). While it is true that the plant Albizia julibrissin is often known as "Persian Silk Tree", the name "Mimosa Tree" is quite common too. We try to use names that are commonly used in the herb industry and those names may not be necessarily be the same as the ones commonly used in the ornamental horticultural industry or in the commercial agriculture. There are many examples of this, but here is one: "Anise" ordinarily means Pimpinella anisum, the common aniseed in the kitchen, but in the commercial vegetable industry it means Foeniculum vulgare azoricum, the plant we call "Florence Fennel" – a totally different plant!
Yes, we are selling Albizia julibrissin. Features such as hardiness and uses can vary considerably in the popular and scientific literature, so I am not surprised that you have seen confusing differences. Hardiness zones are not cast in stone and do vary, sometimes by a lot. I can remember the director of a botanical garden in Alberta calling me up and telling me that he has plants in his collection surviving down to zone 2 when the literature has the lowest zone as 5. We try to give zone information that our customers can rely on, but we are well aware of the shortcomings of the zone system and of the potential for disappointment when plants are are rated hardy for their zone do not survive because of other factors such as lack of snow cover, too much moisture overwinter, unusual temperature extremes, etc. We do update our zones based on feedback from our customers, and because of that our hardiness zone information may not always agree with that published elsewhere.
The medicinal properties of herbs is another area of confusion because one reliable source of information can give one set of properties and another can give a different set – and both can be right (or wrong!). The medical framework is important too: the properties described in the Oriental traditional system can be completely different from those in the Western medical system. For brevity we often truncate the list of known properties in our descriptions, and that alone may make it seem that our descriptions are at odds with other descriptions.
So with these and other potential sources of confusion, what information can be relied on, you may ask. Of course, we'd like to think our catalogue can be relied on, but as you can see we are well aware of its shortcomings. Generally the better known plants that are commonly grown in North America are not as much a problem, but for the lesser known ones we recommend that one research them using a variety of sources and then distill down that information looking for common facts. Then we recommend leaving your mind open to recalibration according to your own experience once you are growing and using them.