Gadenin日本語Get the appBright shade under a canopy is the model
This plant grows perched on branches with a broken canopy overhead. It gets a great deal of light, most of it filtered or reflected, plus short spells of direct sun early and late in the day. It almost never takes full unfiltered sun across the middle of the day, and it never grows in real gloom either.
Translated to a room, that means a position within three feet (1 m) of an east or a shaded south window, or a couple of feet back from a west window. A north window on its own is usually not quite enough to flower, though the plant will survive there and stay green for years, which is exactly why so many people conclude it is a foliage plant.
The simplest test is your own shadow. Hold a hand a foot above the leaves at midday. A crisp shadow with hard edges means too much direct sun. A soft shadow you can clearly make out means about right. No discernible shadow means the plant is in survival light and will not bloom.
What too much and too little look like
Both extremes produce a plant that fails to flower, so it is worth learning to tell them apart by the leaves before you start moving things around. The leaves of this plant are thick and glossy when it is happy, and they change in different ways depending on which way the light is wrong.
| Symptom | Too much light | Too little light |
|---|---|---|
| Leaf color | Pale, yellowish, sometimes reddish on the upper surface | Deep dark green |
| Leaf damage | Dry bleached patches on the sun-facing side | None, leaves simply thin |
| Stem habit | Short internodes, stunted, hard | Long bare stretches between leaf pairs |
| Leaf size | Smaller than normal | Larger and thinner than normal |
| Flowering | Buds abort in the heat | No buds form at all |
A dark green, long-stemmed, leggy plant is the far commoner problem indoors. If you are unsure which way your plant is wrong, it is almost certainly short of light.
Moving a plant into brighter light without burning it
Leaves acclimatize to the light they grew in, and a plant taken straight from a dim corner to a bright window will scorch within days even though the new position is the right one. Move it in stages over two to three weeks.
- Halve the distance, then wait Move the plant halfway to the new position and leave it there for a full week. Check the upper leaves for any pale patch before going further.
- Filter the first week at the window A net curtain or a sheet of tracing paper on the glass for the first seven to ten days lets the leaves toughen up. Remove it gradually rather than all at once.
- Watch the leaves facing the glass Damage always shows first on the surfaces pointing at the window, as a dull pale area that later turns papery. If you see it, pull the plant back a foot (30 cm) and hold there for a fortnight.
- Keep it away from hot glass Leaves touching a sunlit pane cook, whatever the room temperature is. Leave a hand's width of air between the foliage and the glass, and remember the trailing stems swing closer than the pot suggests.
Light through the cool bud-setting weeks
The rest period that triggers flowering is a cool, drier spell, not a dark one. This trips people up: they move the plant to a cool spare room and, because that room is rarely used, it also has the curtains half closed and no lamp. The plant gets the temperature signal and none of the light it needs to build buds, and the result is weak stretched stems and no display.
Choose the brightest cool spot you have, and if the natural light in it is poor, add a simple LED grow lamp running ten to twelve hours a day about a foot (30 cm) above the foliage. The plant will take considerably more light in the cooler months than it will in high summer, because the risk of scorch falls with the temperature.
Turning, and why to stop during buds
Through the growing months, give the pot a quarter turn every week or two. Trailing stems reach hard towards the light and an unturned plant becomes lopsided within a season, with all the flowering tips on one side.
Stop turning as soon as bud swellings appear. Lipstick plant will drop developing buds when its orientation to the light changes, and a plant spun regularly through the bud stage can shed most of a cluster. Mark the rim so you know which way it was facing, and resume turning once the last flower has fallen.
It is worth writing down where the plant sat, and how far from the glass, in the season it flowered well. Rooms change: a tree outside grows, a blind gets replaced, the sun tracks differently. A note of the position that worked is the quickest way to get back to it after a move.