Arirang Orchids logo


Habenaria radiata
1625 Morgan Court, Mountain View, CA 94043


Cypripedium californicum

"Cypripedium californicum" is native to northern California and southern Oregon and is an endangered rare species.

Habitat: In northern California and Southern Oregon, the weather is USDA Zone 8 or 9. Rainfall is 2~3 inches per month, mainly during the winter time. Natural southern limit is San Francisco Bay Area and Marin County in California.
The weather information near the habitat is below:

Ashland, Oregon Weather
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Record
Avg.Low temp(F) 32 33 36 40 45 51 56 55 49 41 36 32 Min.-10
Avg.Hi. temp(F) 48 54 60 65 74 82 90 90 83 69 53 46 Max.115
Rain (inches) 2.5 1.9 1.7 1.4 1.2 0.6 0.4 0.4 0.6 1.4 2.9 3.3

"Arirang Orchids" is located in USDA Zone 9 or 10. That may be the southern limit to cultivate the plants. In colder than natural habitat, thick mulching is needed to protect the plants during the winter time. Also, in warmer areas, refrigerator or plants in plastic foam box with ice may solve the winter dormancy problem.

Description: It may be over 3ft. in height with flowering stem and may have up to 18 small flowers with yellow-green sepals and a whitish pouch with brownish-purple veins inside. It occurs almost always under natural conditions in wetlands 0 to 5,000 feet elevation in riparian areas, near stream banks, seeps, bogs and fens. It is found growing in the dam understory of coniferous forests near streams. Plant communities are yellow pine forest, freshwater marsh, wetland-riparian and California pitcher plant (Darlingtonia californica). ¹)

Medium: We use the following medium: 1 part coconut fiber, 3 parts TurfaceMVP(baseball field covering material), 2 parts small Perite, 1/4 part charcoal, 1/4 part leaf mould. This medium contains less organic materials with good air circulation and moisture content with necessary nutrients for the plants. Underground bugs can multiply in wet and decayed materials during the winter time. The ground worms eat the roots and new leaf buds. Too much organic medium invites the worms so use a lot of inorganic media.

Water and fertilizer requirements: Keep soil moist at all times. Do not dry out rootzone at all times. During the wet season there is no need to water. Rain water is better,but tap water also works in our area. When they begin growth during the spring, more moisture is needed. The fertilizer application is 1/8 strength all-purpose fertilizer every 2 weeks during the growth period. High concentration of fertilizer to the small seedlings is very harmful.

Insects and bugs: Sometimes cats, birds and ground squirrels dig the pot surfaces. Earthworms and other critters inside the medium chew up the young roots and buds when the weather is cold and wet.

Containers: 2 or 3 years growth-size containers are enough for the plants.

Planting time: The preferred time is during the dormant periods (November to February).

Temperature: Above the pot, over 100F~105F for a few hours has no harmful effect on the plants. But medium in the pot (rootzone) temperature should be kept as cool as possible during the hot summer (maximum temperature around 80F). When medium temperature is above 90F during the summertime, the plants die within a few days. The plant is hardy at 21F.

Mulching: A lot of moss can grow on the wet medium surface all year round. Therefore shredded pine needles on the surface of the pots are needed when planting. If the weather is colder than natural habitat, use mulch during the winter months.

Air circulation: Very good air circulation is necessary at all times. So do not grow in enclosed areas, greenhouses, or wind protected areas.

Repotting: When the plants are overgrown or the medium becomes soured, replanting should be considered. Lightly cover growth buds with medium and mulch it with pine needles to prevent moss growing on the surface and protect the medium from washing out of the pot.

Light conditions:Leaves are relatively small and compact compared to other Cypripedium species, therefore it can withstand strong light. 2 or 3 hours morning sun and half shade during the day is the best condition.

Flowering: Depending on geographic location and weather conditions, end of May to July. The flowering stem may have upwards of 12 or more small flowers with yellow-green sepals and a whitish pouch with brownish-purple veins inside. The flowering prime time is the end of June. It takes about 4~6 years out of flasks to flower. Flowers are about 1 1/2inches with a delicate lemon fragrance lasting 3 or 4 weeks in consecutive blooming on inflorescent.

Available Plants: Small seedlings out of flask are hard to establish and grow to adult plants because of the sensitivity of outside conditions and plant physiological characteristics. We sell only the 2 years out of flask plants in pots.

Vernalization: Please refer to the weather conditions in the habitat and Mountain View, CA on our home page. We grow Cyp. californicum outside all year around.

¹) "The Wild Orchids of California" by Ronald A. Coleman (Page 62-64)

Habenaria radiata (Egret Flower)

Habenaria radiata is native to Korea,China, and Japan.
Flowers with honey-holding spur resemble flying white egrets. Plant height including flower stalk is 6~12 inches. Plant has a 3~ 12" long inflorescence having up to 12~15 flowers. The flower size is 1.5" on an erect and slender flower stem.

Soil media: A mix 1/2 garden sand and 1/2 powdered peat moss with shredded pine needle mulch works well. The plants are growing in acidic soil in their natural habitat, so include some sphagnum moss in the mix.
Soil/medium should be 4~5 inches deep.

Light conditions: 80~100% sun with good ventilation.
Grow outside for more sunlight and air movement. When plants are grown in shady areas, growth is retarded and aphids multiply under the leaves, and flower quality will be poor.

Water requirements: Keep wet at all times. Plants need more moisture during the growing season. When mulching material is dry, it is time to water. Hold water from mid-October until mid-November to mature the underground corms.

Fertilizing: Apply "Osmocote"(a few grains per square inch) once a year during early March, on top of pine needles, when planting the corms.
Apply 1/8 strength all-purpose fertilizer every 3 weeks.

Planting: Early March when the corms are sprouting, plant the corms 1/2" deep and mulch with dry pine needles. On top of the pine needle mulching, apply some "Osmocote".
After planting, do not disturb the pot. It takes about 3 weeks to see the first green sprout above the ground surface. Do not move the pot position. After flowering, moving the pots is fine.

Hardiness: In USDA Zone 9-10 area, corms need extra chilling in refrigerator. In weather conditions similar to natural habitat (Suwon, Korea: USDA Plant Hardiness Zone, 8b or 9a), just mulching the corms should be enough.

Dormancy: After collecting the corms in early November, mix with wet vermiculite and store the corms in a cold place (~35F). They may be put in the Styrofoam picnic box with ice. Replace the ice every week.
Or put the wet vermiculite and corms in the crisper area of the refrigerator. Some air contact is necessary to protect the corms from fungus infection during the vernalization periods. Keep wet until early March.
During November to early March, corms need some air circulation, so do not store in sealed plastic bags.

Bugs and diseases: Under good cultural practices bugs and diseases should not be a problem. If growing in shady area, aphids may be found under the leaves. So control the ants and aphids and give plants more sunlight and air circulation.

Flowering: The flowering period is summer to early autumn.

Bletilla yunnanensis

Bletilla yunnanensis is endemic to China (Yunnan).
Around 3~9" long pleated leaves bear inflorescence with flowers. Flower color is pink, red, reddish spots in lips with white background. This species has cormlike pseudobulbs with consecutive flowering in late spring to early summer.

Temperature: It's hardy outdoors around -10F with mulch. It grows outside year around.

Light: It needs a lot of sunlight. If grown under the shade, flower buds will not develop next year.

Water: During the growing season, ample supply of water is necessary. During the winter when the leaves dry out, water it every three weeks.

Fertilizer: No fertilizer is necessary with organic medium.

Medium: 2 parts potting soil, 1 part small perlite and 1/4 part peat.
Medium should have good drainage and water holding capacity.

Repotting:If root zone is crowded, it is time to repot. In one or two years, repot during the dormant period (November to February).

Spathoglottis gracilis

Spathoglottis is a genus of tropical, terrestrial orchids with more than 40 species. It produces successive flowering over months. Flower color is yellow. This plant offers year round yellow color in landscape ground beds in warm climates.
This species is native to New Guinea, northern Australia and the islands of the Pacific Ocean.

Light:Plants grow best under bright light in green house or 50% shade.

Water: Keep plants evenly moist and they will tolerate periodic drying.
Fungal problems may occur on small seedlings when applying too much moisture.
During the growing season, ample water is needed. In wintertime, water once every two or three weeks.

Temperature:Keeping the plant above 50°F is ideal for growth and to initiate flowers.
In colder area, winter protection is necessary. During cold periods(mid 40's), keeping the medium dry that protects roots from rotting.

Potting: Root growth is vigorous. Therefore repot every year during spring or winter.

Flower: Yellow fowers bloom consecutively.
Flower size is about 2 inches across.

Air movement:Good air circulation is necessary especially during the winter when humidity is high.

Medium: 1/2 big perlite and 1/2 potting soil should work.
This medium has a property of good aeration and moisture retention.
These plants have robust root systems so the pots need to have ample root space.

Temperature: Day time temperatures are above 75°F, night time above 65°F.
Temperature below 40°F may cause dropping leaves. So the minimum temperature to cultivate is around 50°F.

Pests or disease: Under good air circulation, there is no problem. Spider mite, mealy bug are found sometimes. Too much water, high air humidity and cold environments can cause the crown rot.

Spiranthes sinensis

Spiranthes is commonly called "Ladies'-tresses".

Distribution: Widespread in marshy areas in south eastern coast areas of Australia, China and other parts of Asia, Pacific Islands, New Zealand and New Guinea.

Leaves: It is a terrestrial herb comprising 3 to 5 leaves up to 10cm long.

Flowers: The small, tubular-shaped flowers are bright pink with a white labellum and occur in a long spike which has a twisted form.
Fowering time is spring, summer and autumn after which the plants become dormant and above ground parts die back.

Light: 50% sun during the active growing period.
Under full sun, the plant dires out easily and growth rate is slow.

Medium:Soil medium is 3 fine perlite, 3 Turface, 1/2 potting soil and 1/2 peat moss mix.
The medium should have good drainage, air circulaton and NOT soggy.

Air circulation: When growing this plant inside greenhouse, it gets weak and flowers poorly.
Grow this plant outside. Good air circulation is beneficial.

Water:Always wet with good drainage.

Spiranthes cernua odorata

Habitat: Spiranthes cernua odorata has vanilla or jasmine fragrance.
Commonly called the "Nodding Ladies'-tresses", Spiranthes cernua is a species from eastern Canada to the central and eastern United States.

Flower: It has pure white spiral flowers on the inflorescence and flowering time is summer to autumn.

Light: Half shade to full sun with good air movement.

Medium: Soil medium is 3 fine perlite, 3 Turface, 1/2 potting soil and 1/2 peat moss mix.

Water: Keep the medium always moist.

E-mail :
Copyright © 2015-2016Arirang Orchids
Last Updated: Feb. 26, 2015