November 23, 2025, 6:13 am | Read time: 4 minutes
Few plants symbolize the Advent season as much as the poinsettia. Its bright bracts bring light to dark days until they gradually fade. For many, this is a moment of disappointment: Did they do something wrong? In most cases, the answer is a little yes—and a little no. The poinsettia is more sensitive than it appears. myHOMEBOOK plant expert Franka Kruse-Gering explains why the poinsettia loses its color and what can be done by considering its biological clock.
Why the Poinsettia Has Colorful Leaves
Its red, pink, or white “petals” are not actually flowers but so-called bracts. The true flowers of the poinsettia are tiny, inconspicuous, and sit as small yellow-green buttons in the center.
The colorful bracts are just the stage, not the star. In nature, they are meant to attract insects to pollinate the true flowers. In its native Mexico, the poinsettia blooms around the winter solstice when daylight is short. Only these long nights trigger the bracts’ coloration—a clever trick to attract attention in the dark winter.
Why the Poinsettia Loses Its Color
When the poinsettia loses its bright color, it can be due to various reasons. Some are quite natural—others are due to care mistakes or unfavorable environmental conditions.
The Colorful Leaves of the Poinsettia Are Not Flowers
The Difference Between Long-Day and Short-Day Plants
Natural Causes
End of the Blooming Period
After a few weeks, the poinsettia’s blooming period simply ends. The small yellow-green flowers in the center—the so-called cyathia—wilt, and thus the colorful bracts lose their purpose. They attracted insects as long as the plant wanted to be pollinated. Once this phase ends, the poinsettia returns to its original green.
Natural Aging Process
Like any flowering plant, the poinsettia goes through a life cycle with active and resting phases. After the vibrant period in winter, it retreats to gather new strength. This is expressed by the fading of colors and sometimes by leaf drop—no cause for concern, but a sign of its natural rhythm.
Biological Rhythm–the Short-Day Plant
The poinsettia colors its bracts only when the nights are long enough. This signal—the so-called short-day reaction—stimulates the production of pigments. Once the blooming phase is over or the light conditions change, the plant stops producing pigments. As a result, it slowly loses its festive tone and turns green again.
Care Mistakes and Environmental Factors
Too Little Light
The poinsettia loves brightness. If it is too dark, it cannot produce strong pigments—the bracts become paler or greenish. Especially after the holidays, when the days are still short, lack of light is one of the most common causes of color loss. A bright spot right by the window (but without drafts) helps maintain the color longer.
Too High Temperatures
Air that is too warm is challenging for the poinsettia. Temperatures above 72 degrees accelerate its metabolism, causing the plant to use more energy and lose its color faster. Ideally, maintain a consistent 64 to 68 degrees—not too hot, not too cool.
Drafts and Temperature Fluctuations
Even a brief cold shock, such as during transport or ventilation, can cause stress. The poinsettia reacts sensitively with spots, color loss, or even leaf drop. Therefore: avoid places above the heater or next to the balcony door.
Incorrect Watering
Waterlogging and dry soil are the biggest enemies. Too much water causes the roots to rot, too little dries them out—both disrupt nutrient supply and thus color intensity. The soil should always be slightly moist but never wet. The best method: water from below and pour off excess water after a few minutes.
Dry Heating Air
It depletes the plant’s moisture, first visible on the bracts: the edges become pale, and the color loses depth. A small bowl of water on the heater or occasionally spraying the air around the plant can help improve the room climate.