This is the exact device that we have:
https://www.amazon.com/dp/B00006LS81/
That's the Brother PT-2600. I don't know if it's the best or even a particularly good one, but it has done very well for us and we have labeled hundreds of plants with it. Labels we printed at least 5 years ago still look the same as they did the day we printed them.
The tape we use is this:
https://www.amazon.com/dp/B004I2H19O/
It's a black ink on clear tape. It works very nicely. You can print two lines so we do the formatting like this:
Latin name
'Cultivar name'
and it prints in a very nice font that is easy to read.
