Pogostemon helferi is the scientific name for ‘Downoi’. Pronounced phonetically, ‘dao noi’ means little star in the Thai dialect. It is found in rivers bordering Burma and Thailand in fast flowing water, growing in an emersed fashion over rocks during the dry season. Submersed, P. helferi sheds its woody appearance for a striking crown of leaves, where it can carpet across a sandy substrate, in a variety of settings.
While it prefers to be in kept harder water, P. helferi can be coaxed into growing in soft water tanks using high light, full-spectrum bulbs and CO2 injection. In lower light, the crown of leaves will grow as large as six inches across to capture more light. P. helferi will also survive in unheated tanks. Surprisingly, it can also be attached to rocks like Anubias. Although regarded as an ‘advanced’ plant, P. helferi can be enjoyed by all because of its forgiving nature. Indeed, one can scarcely be faulted for falling in love with this diminutive plant.