The Hono Hono Orchid or Dendrobium anosmum, has been a Hawaiian favorite for many years. The Hono Hono in Hawaiian refers to the plants’ growth habit of alternating leaves, very similar to the introduced weed, Commelina diffusa or Wandering Jew. Oddly it’s the flowers and their exquisite fragrance and not the leaves that keep people exited about growing this orchid. Another interesting fact about this orchid is that its botanical name anosmum actually means without scent! My only guess is that some taxonomist was probably looking at a dried sample, because there is no mistaking the unique fragrance that the Hono Hono has. For this article and simplicity sake, I am including the related species and hybrids of Dendrobium anosmum together, since they share similar cultural requirements.
To grow the Hono Hono orchid well we must first learn a little about it and where it comes from. Its origin is quite widespread throughout Southeast Asia. This tells us that their dry season is opposite from ours in Hawaii, therefore we need to manipulate our culture to provide the proper environment, enabling us to flower the Hono Hono well.
Here is a Hono Hono checklist.
This cycle runs from December to February. Dormancy begins when nighttime temperatures drop and watering is reduced. Keeping the orchids dry during our wet season could be difficult. One way is to move them under cover (Polypropylene roof or under the eaves of the house). If the Hono Hono does not go into dormancy, flowering will be poor. Next season’s new growth will emerge before the buds and will compete with bud formation.
Decrease watering to two times per week, making sure that the orchids
are drying between waterings. Do not fertilize, tap out any timed released
fertilizer from the pots. The Hono Hono Rule: The day that you will
eat the most (Thanksgiving Day), is the day that you starve your Hono
Hono. It is a good sign when the leaves begin to turn yellow and fall off.
The Hono Hono is actually pulling back and is storing all of its energy
into the plump and bare stems (pseudobulbs).
Buds should begin to form along bare stems. At this time they are very
vulnerable to flower thrips, which will turn the small buds brown,
resulting in few to no flowers. Next years’ shoots will start forming from
the base of the flowering cane.
The flowering cycle normally occurs during the months of March to May. Using several different species, hybridizers are making new crosses that bloom at slightly different times. But generally most Hono Hono will flower during this time of year.
The flower buds should become larger and begin flowering. Increase
watering to once per day. Check flowers for unusual markings or
crippling. This could be symptoms of virus. These plants need to be
culled, as there is no cure for viruses. Try to keep water off the flowers.
The delicate flowers are susceptible to Botrytis or Flower Blight Fungus.
Continue to watch for flower thrips.
This is the best time of year that the Hono Hono should be planted or repotted. As new shoots develop so will the new roots. Planting should be done when the new shoots are 4-5 inches long and the emerging roots are one to two inches long. Avoid damaging the tender root tips. The most common media used with pots, is a bark mixture (Approximately 3 parts medium orchid bark, 3 parts peat moss, and 1 part perlite). My favorite is New Zealand Sphagnum Moss. Others like to mount them on Hapuu (Hawaiian Tree Fern), or onto cork. One caution when mounting is that you really need to water often as they tend to dry a lot quicker.
Continue watering every day or more if possible. Begin fertilizing with a
water soluble type of fertilizer. The new growths emerging from the
base of the recently bloomed stems should be about four inches long with
new roots forming, before the old stem is removed. Make sure that you
sterilize your pruner between plants (A propane torch is best). Viruses
are the most deadly disease of Hono Hono and is mostly spread by your
pruner. Label cut stems and cut them into 4-5 inch segments. Remember
that keikis will only form on areas of the stem where the nodes that have
not flowered. Place them in a shallow tray containing 3 parts peat moss
and 1 part #2 perlite mix. Keep them in a shady area and allow the keikis
to emerge. Grow keikis in these trays for a year. Repot them into their
flowering pots when new growths and roots begin to appear. These plants
should flower for the first time in two growing seasons. Treat the area for
slugs as they love to feed on the tender new shoots.
Older plants should be repotted every two years. As the media ages, it
begins to breakdown becoming sour and soggy. Fertilization causes
pH of the media to become too low or acid. Salts begin to accumulate to
toxic levels. The root system soon dies. From the third year and beyond,
you will notice that the stems will become shorter and the flowering will
become less and less.
During this time the Hono Hono is in its most active growing stage. They are heavy feeders and want abundant water. Grow them in an area of filtered sunlight. Avoid direct midday sunlight, unless you are close to the mountains and have a lot of cloud cover.
Continue watering once per day or more. Fertilize twice a week with a
one half strength, balanced, water soluble fertilizer. Inspect new shoots
August for thrip damage (browning of the new leaves in the whorl). Also
September caterpillars can affect the new leaves. Inspect the undersides of the leaves
October for spider mite damage (silvering to browning, with tiny red dots). Stop
November fertilizing by mid November.
By following some of these basic rules of growing the Hono Hono, you too can be successful. By collecting the different types of Hono Hono, you may be able to stretch their blooming season from February to June. Just imagine having the beautiful flowers and wonderful fragrance for one third of the year! The best thing about growing Hono Hono orchids is that everyone is able to share their extra keikis with friends. This is truly what makes orchid growing fun in Hawaii!
*Special thanks to Scot Mitamura who is an Orchid Horticulturalist for the Honolulu Botanical Gardens and has been growing and hybridizing orchids for over 46 years. He can be reached at firstname.lastname@example.org.
*Also special thanks to Mel Waki for letting us use his beatiful Hono-Hono Pictures.