We would also recommend checking out Bonsai Tonight for more information about growing these orchids. Jonas has published several good articles on Egret Orchids (Part 1, Part 2, Part 3) focusing on different soil media and their effects on blooms and propagation.

More info on Habenaria radiata

One of Japan’s most famous orchids is the delicate terrestrial species, the White Egret Orchid , Habanera radiata. This plant’s flower looks like a snowy egret with its display plumage puffed out. Despite being well known worldwide, this species is imperiled in the wild.

Each grass-like leaf of the egret orchid, up to 7 in number, are between 5 - 20 cm (2-8 in) long and about 1 cm (0.5 in) wide. New leaves are formed each spring, starting out as small leafy growths that extend upward over the summer. They are arranged alternately up a single stem that continues on as an unbranched flower spike up to 50 cm tall, but usually much shorter than that. Flowering begins in late July and peaks in August.

The Egret Orchid's flower stalk holds anywhere from 1 to 8 flowers, each being around 4 cm wide. The extravagant lip as well as the petals are pristine white; whereas, the sepals are simple, small and green. Without a doubt, the lip steals the show—it has three main lobes, the two biggest extend laterally and are highly fringed, while the center lobe is simple, elongated, and pointing downward.

The lateral lobes of the lip give it the distinctive “egret flower” shape, while the petals, also pure white and lightly toothed, splay upwards, looking much like wings, and giving the flower an almost angelic appeal. The column itself is interesting, a trident shaped affair, bright green, with two yellow, elongated pollinia at the front and in full view, just waiting for a ride on a pollinator’s back or head. If this weren’t remarkable enough, the flower also boasts a large nectary, or spur, green in color and extending up to 8 cm long in a graceful arc just below the lip.  Truly, this is a regal flower.

The plant grows from a small underground tuber, no more than a couple centimeters long, with its associated network of fleshy, unbranched roots. Being a deciduous species, this tuber serves as an energy source early in its growth cycle, allowing new leaves and the flower spike to form. Over the summer new bulbs form on short underground stems (stolons) and the old bulb slowly diminishes and dies by early autumn.  A healthy growth can produce up to 3 replacement bulbs, and sometimes more. The new bulbs are fully formed by late October and leaf antithesis occurs at that time. A short time later, the roots grown that season die back as well and the newly formed bulbs become separate, individual plants.

The White Egret Orchid is a small terrestrial orchid from grassy wetlands and seepage slopes throughout Japan, the Korean Peninsula, and some parts of eastern China. This species is in rapid decline over its entire range.  In preagricultural times these plants grew in lowland bogs and marshes in the very same areas where rice patties were to be situated later on. Rice cultivation increased, which was then followed by urbanization, and as a consequence, in lowland areas this species became more and more rare in the wild.

Nowadays, Habenaria radiata exists mostly in upland bogs and seepage slopes in moderate to high mountains (over 500 meters elevation).  These areas are not suitable for agriculture in most cases and so this plant (along with many other rare species) has found its last refuge in modern Japan. While it is found on all of Japan’s main islands it is endangered throughout its range and is even extinguished in some prefectures. 

Luckily, The White Egret Orchid is easy to cultivate.  The trick to growing the egret flower is simple – grow them as you would any bog orchid or pitcher-plant in summer and very importantly, dry the bulbs off in winter.  Being plants of sunny, wet bogs, they do not appreciate windowsill culture and planting them in normal potting soil will mean their demise rapidly from fungal or bacterial attack.  

You will receive your Egret Orchid as small bulbs (also called tubers or corms). They will be leaf-less, and nearly dead looking. Light brown bulbs with a bit of fuzzy hair are the healthiest, but even dark brown ones will grow if handled well. If you get them in the fall, I recommend submerging them in a dilute fungicide solution for a few minutes.   To store these bulbs for the winter, dry them out quite a bit until they feel dry to the touch, and place them in a freezer bag with a bit of very slightly damp vermiculite or perlite.  Put this in a cool place over winter, below 10 C (50 F) is best.  You can also store them in a refrigerator, though this isn’t necessary as long as the temperature doesn’t exceed 12 C (54 F).  Avoid freezing them.  Since they will have to rest all winter, it is a good idea to check them once in a while for fungal attack.  Often a bulb will spoil and needs to be removed so that it doesn’t infect others.

In early spring the bulbs should be planted just below the surface, perhaps 1 cm (0.5 inch) deep.  Plant them pointy side up.  Once potted, put them in a sunny, warm position and keep them moist, but not wet.  Be patient, they can take weeks to start to grow, but once they do, increase watering. When the days truly get hot and the Egret Orchids are growing strong, water them such that they remain essentially wet.  I’m careful with not letting them get waterlogged however and I have found them to be poor container bog plants.  The water you use should be relatively low in dissolved minerals, but don’t worry too much about that.  More important is that you let the chlorine dissipate before watering – a container sitting out for 48 hours is enough to accomplish that. 

You can grow Egret Orchids in any mix that is water retaining and acidic in reaction. I use a natural weathered pumice called kanuma, peat moss, and a bit of sand (ratio of 1 : 1 : 1/2) and top dress with a thin layer of dried sphagnum fiber. You can use anything similar, for instance perlite mixed with sand and peat, for example. Some people grow these orchids in pure live sphagnum sitting on top of a bed of pure silica sand. I don’t think that is necessary and if you’ve ever tried, you’ll know how difficult it is to keep sphagnum alive and happy!

The White Egret Orchids will be full grown by mid-July and will start throwing out their flower spikes. Be careful for bug attacks at this time since the delicate buds are easily destroyed or disfigured.  Once they are finished flowering, continue growing them wet until the heat of summer is over.  In the cooler days of early fall keep them just moist.  Once nights get below 15 C (60 F) Egret Orchid will begin to go dormant.  You can remove the dead growths at that time. For winter’s rest, keep the bulbs in the same pot, but dry it off bit by bit until is is nearly completely dry, but not truly so (the dryness of bagged tobacco is perfect).  Do not bring them into a heated area to do this, instead allow it to happen slowly by not watering at all.  The addition of small amounts of water every few weeks is necessary, particularly if the pot is kept in low humidity (for example a basement).  Keep the White Egret Orchid cool and dry all winter in their pot – 0 to 10 degrees C (32 to 50 F) is ideal.

In March or early April take the plants out of the pot.  Recover all newly formed bulbs and throw away the old bulbs and dead roots.  The new bulbs will be bright tan or light brown in color and firm to the touch. The old bulbs will be dark and soft.  Replant them immediately to start the new growth cycle.

Regarding fertilizer – I do fertilize mine regularly with a very diluted inorganic fertilizer with micronutrients.  The key is to not overdo it.  In May and June, when the plants are at peak growth, I fertilize about every other week, but make sure that the pots are fully flushed with fresh water to avoid salt build up.  Usually the monsoon rains take care of that for me.  You can use organic based fertilizers such as fish emulsion or seaweed based extracts as well, but it isn’t necessary.

The tricks to keeping these beautiful terrestrial orchids happy are:  renew the growing medium each season, grow them in a sunny location, use plenty of chlorine free water while in growth cycle, fertilize carefully at the beginning of the growth cycle, and provide a cool, dry winter rest.  Follow these basic instructions and you will be rewarded with lovely egret flowers each summer. You may also be amazed at how many new plants grow each season.

Rare in the wild, yet easy to grow, this lovely species is a true gem of the Far East. Anyone who is in for a bit of a challenge and is capable of say baking a cake from scratch ought to give this one a try. You will not be disappointed.