Gadenin日本語Get the appWhat the flowers are and when they come
The wind orchid, a miniature epiphytic orchid with a fan of stiff curved leaves, flowers in the warm part of the year, usually early to midsummer. Short spikes push out from between the leaves low on the fan, each carrying a handful of white star-shaped flowers with a long slender spur trailing behind. A mature fan typically produces one or two spikes; a clump of several fans can carry a dozen flowers at once.
The scent is the reason many people grow it. It is strong, sweet and jasmine-like, and it appears in the evening and through the night rather than in the daytime, which is a signal that the flowers are built for night-flying moths and explains the long spur. A single plant will perfume a room after dark and be almost scentless at noon.
Flowers last two to three weeks in cool conditions, less in heat. They are not affected by the plant being moved once open, so there is no need to leave a flowering plant in a poor position.
Buds are set in winter, not in summer
This is the point on which everything turns. The flower spikes that emerge in early summer were initiated during the previous winter, in response to a long cold spell. A plant that is warm through winter has no signal to initiate them, and no amount of feeding, light or fertilizer in spring can add them afterward. When someone says their plant grows well but never flowers, this is almost always the reason.
The requirement is a run of eight to twelve weeks with the plant kept between 35F and 50F (2C and 10C), bright, and close to dry. Night temperatures matter more than daytime ones, and a daily swing between a chilly night and a mild sunny day is better than a constant cool. Brief dips to just above freezing do no harm; freezing solid does.
Keep the light strong through that rest. A cold dark cupboard is not a winter rest, it is storage, and a plant treated that way emerges weak and still does not flower. Cold and bright together are what set buds. An unheated porch, a cold frame, a garage with a window or an unheated spare room all work.
Water lightly through the rest, roughly every two or three weeks and only enough to keep the roots from shriveling, on a mild morning. Stop feeding entirely. The plant is not growing and cannot use it.
The most common mistake is cutting the rest short by bringing the plant into warmth early. Eight weeks is a minimum, not a target. A plant given four weeks of cold usually produces a single weak spike or none at all.
Everything else that has to be right
The cold rest is necessary but not sufficient. A plant has to have built enough reserve during the previous growing season to have something to flower with, and that reserve comes from light, water and feeding through summer. The table below lists what must be true for a fan to bloom.
| Requirement | What it means in practice | What happens if it is missing |
|---|---|---|
| Mature fan | At least four to five leaves, typically three years from a seedling | Plant grows but is simply too young to flower |
| Strong summer light | Bright filtered shade, leaves medium green not dark | Soft dark leaves, plenty of growth, no spikes |
| Full growing season feed | Quarter-strength balanced feed every second or third watering | Thin new growth, one weak spike at best |
| Cold winter rest | Eight to twelve weeks at 35F to 50F (2C to 10C), bright | No buds initiated at all, the usual cause of failure |
| Winter dryness | Watered lightly every two to three weeks, no feed | Rot, or soft growth that suppresses budding |
| Undisturbed spring | No repotting once spikes are visible | Spikes stall, yellow and drop before opening |
Spikes, bud drop and the weeks before opening
The first sign is a blunt green point emerging from a leaf axil low on the fan, easily mistaken for a new root until it lifts and stiffens. From there to open flower takes roughly four to six weeks. During that stretch keep conditions steady, water normally, and continue feeding lightly until the first flower opens.
Buds that yellow and drop before opening are nearly always an environmental shock rather than a pest. A sudden move into much stronger sun, a hot dry spell with no increase in watering, letting the mound go bone dry for several days, or repotting after spikes appear will all cause it. Cold drafts and cooking gas fumes indoors do the same. Once a bud drops it does not come back, but the plant will normally flower again the following year without any correction beyond leaving it alone.
If a spike appears very late, well into the hot part of summer, expect fewer flowers on it. That usually indicates a rest that was on the short side, and the correction is made the following winter, not now.
After the flowers finish
Cut the spent spike off close to the leaf fan with a sterile blade once the last flower has withered. Unlike some orchids, these spikes do not rebloom from the same stem, and leaving a dying spike in place only invites rot right at the crown where you least want it.
Do not let the plant set seed unless you intend to. A pollinated flower forms a long green pod that takes many months to ripen and draws heavily on a small plant, often at the cost of the following year's flowering. If a pod forms and you do not want it, snap it off early.
Resume full feeding immediately after flowering. The rest of the summer is when the plant builds the fan and the roots that will carry next year's blooms, so this is the least useful time to ease off. Keep it growing hard until autumn nights cool and the root tips harden over.
What to write down for next year
Flowering is settled by conditions half a year earlier, so a written record is the only way to connect cause to effect. Log the date the plant went into its cold position, the date it came out, and the lowest and average night temperatures in between, taken from a minimum-reading thermometer left beside the plant.
Then log the date the first spike tip appeared, the date the first flower opened, how many spikes each fan produced, and how many flowers each spike carried. Set that against the winter figures. Two seasons of this will tell you precisely how many weeks of cold your plant needs, which is more useful than any general figure.
Note any bud drop and what happened in the days before it, including any move, any missed watering and any hot spell. Bud drop has a cause and the cause is usually three to five days earlier, which is exactly the sort of detail memory loses and a note keeps.