The Spathiphyllum, commonly known as the Peace Lily, is a popular houseplant native to tropical regions. Its elegant white “flower” is not a true flower botanically.
The prominent white part resembling a petal is a modified leaf called a spathe, which attracts pollinators. The spathe partially encloses the true flowers, which are tiny and densely packed onto a fleshy central spike called the spadix. Understanding this structure helps in properly caring for the plant’s inflorescence.
Removing Spent Blooms
Removing the spent bloom, a process known as deadheading, is a necessary step to maintain the plant’s appearance and redirect energy toward new growth. A peace lily bloom has reached the end of its cycle when the white spathe and the central spadix begin to turn brown, wilt, or shrivel. This discoloration indicates that the reproductive cycle is complete and the structure is no longer performing its function.
Once you identify a fully spent bloom, you must remove the entire flower stalk, or peduncle, to prevent the plant from wasting energy on a dying structure. Use clean, sharp shears or scissors to make a precise cut, which helps to avoid introducing pathogens into the plant tissue. Follow the flower stalk down to the base of the plant, near the soil line, or where the peduncle emerges from the foliage.
Make the cut as close to the base as possible to eliminate the entire stem, taking care not to damage surrounding leaves or new growth. Removing the whole stalk encourages the plant to produce new leaves and future blooms. Cutting at a 45-degree angle can also help prevent water from collecting on the wound, reducing the risk of fungal infection.
Understanding Flower Discoloration
Peace Lily spathes sometimes change color prematurely, which signals an environmental imbalance rather than the natural end of the bloom cycle. A common issue is the white spathe turning partially or entirely green, which often occurs due to excessive light exposure. Since the spathe is a modified leaf, too much bright, indirect light can cause it to develop chlorophyll for photosynthesis, essentially reverting to a leaf function.
To correct a spathe that is greening, the plant should be moved slightly away from its current light source to a location with more filtered light. Greening can also be a sign of over-fertilization, as excess nutrients can stimulate chlorophyll production in the spathe. In contrast, browning or blackening on the spathe is usually a sign of environmental stress, such as low humidity or chemical burn.
Peace Lilies are sensitive to chemicals in tap water, such as chlorine and fluoride, which can cause the spathe and leaf tips to brown. If this occurs, switch to using distilled or filtered water for irrigation. Over-fertilization causes salt buildup that can also scorch the spathe. To remedy salt buildup, flush the soil thoroughly with clean water to wash away the excess mineral salts.
Promoting Future Flowering Cycles
The primary factor determining new blooms is the quality and quantity of light the plant receives. While Peace Lilies tolerate low-light conditions, they consistently flower only when provided with sufficient bright, indirect light. Placing the plant near a north-facing window, or a shaded east or west window, provides the necessary light intensity without the risk of scorching the foliage.
Fertilization plays a supportive role in bloom initiation and development during the plant’s active growing season, typically spring and summer. Peace Lilies are not heavy feeders, so a balanced, water-soluble houseplant fertilizer should be applied sparingly, at half or quarter strength, every six to eight weeks. Using a fertilizer with a slightly higher phosphorus content can specifically help encourage flower production.
Consistent soil moisture, not sogginess, is also required to maintain the plant’s health, which is a prerequisite for flowering. The plant signals a need for water by dramatically drooping its leaves, a cue that should prompt immediate watering. Maintaining high ambient humidity, ideally above 50%, mirrors the plant’s native tropical habitat and significantly enhances its ability to produce new spathes.