POGOSTEMON HELFERI also known as Downoi to most is one of the most beautiful foreground aquarium plants. It is an easy stem plant to grow, and propagate if you have the correct growing conditions.
Downoi will grow to 2 inches tall underneath high light but will grow slightly taller in moderate lighting conditions. It prefers a fertile substrate bed, at least moderate lighting, and some carbon dioxide to do well. Its growth rate is moderate for a stem plant.
Downoi forms many side shoots, which develop small roots, these side shoots can then be snipped off and replanted.
The best way to plant Downoi when first received is to leave the portion together and bury about 1/8" in your substrate. Once it acclimates to your water parameters then you can snip off the stems and plant each stem individually to give you more coverage.
I have found when you leave the "portion" together rather than breaking it apart the plant is less likely to go into shock or have less die off.
You are buying one portion, approx 3 rooted stems.