Calla lilies (Zantedeschia spp.) are not always white. While the classic white variety (Zantedeschia aethiopica) is most familiar, these plants naturally exhibit a range of colors, including green, yellow, pink, and purple. Green flowers can occur due to genetic traits or hybridization, where pigments like chlorophyll (responsible for green color) dominate over other pigments that produce white or colored blooms.
The green color in calla lily flowers often results from chlorophyll, the same pigment found in leaves. In some cultivars or under specific conditions, chlorophyll remains active in the spathe (the showy part of the flower) during blooming. This can happen when: - The plant is young, and the spathe hasn’t fully matured to its final color. - The variety is genetically predisposed to retain chlorophyll in floral tissues. - Environmental factors (e.g., light exposure) boost chlorophyll production in the spathe.
Growing conditions significantly impact calla lily coloration. Key factors include: - Light Levels: Excessive shade can cause greener flowers, as the plant produces more chlorophyll to compensate for low light. Conversely, bright indirect light encourages whiter blooms in white varieties. - Nutrient Imbalance: High nitrogen levels promote leafy growth and chlorophyll production, potentially leading to greener spathes. - Temperature: Cooler temperatures may slow pigment transitions, causing flowers to retain green hues longer.
Calla lily flowers often change color as they age. A green spathe may gradually turn white or another color as it matures. This is because: - Chlorophyll breaks down, revealing underlying pigments. - Anthocyanins (responsible for red/purple hues) or carotenoids (yellow/orange) may develop later in the bloom cycle. If the flower is cut or fades while still green, it may never reach its expected color.
Some calla lily cultivars are bred for green flowers. Examples include: - Zantedeschia 'Green Goddess', known for its vibrant green spathes. - Hybrid varieties with mixed parentage, where green pigmentation is intentionally selected. Always check the cultivar’s expected color when purchasing, as green may be a feature, not a flaw.
Abnormal green coloration can signal stress: - Viral Infections: Certain viruses disrupt pigment production, causing uneven color or greening. - Nutrient Deficiencies: Lack of phosphorus or potassium may affect flower color. - Water Stress: Overwatering or drought can alter metabolic processes, including pigment synthesis.
Spontaneous mutations or cross-pollination can lead to green flowers in typically white varieties. These changes may affect: - Genes controlling anthocyanin production. - Chlorophyll distribution in floral tissues. Such variations are common in cultivated plants and may stabilize in new cultivars.
