Calla Lily Growth Stages From Rhizome to Dormancy

The Calla Lily, known for its elegant, trumpet-shaped blooms, is a popular choice for gardens and containers. To successfully cultivate this plant, it is helpful to understand its life cycle, from the initial rhizome to its period of rest. Following the plant through its distinct phases ensures it receives the right care at the right time for healthy growth.

Rhizome to Sprout

The Calla Lily’s journey begins with a rhizome, a fleshy, underground stem that stores nutrients. These rhizomes are firm and plump, with a flattened bottom and a top side featuring visible growth points, often called “eyes.” Place the rhizome in the soil with these growing tips facing upwards to ensure the shoot grows correctly.

Plant the rhizomes about four inches deep and space them approximately twelve inches apart. This spacing allows enough room for the root system to develop. After placing the rhizome in well-draining soil, water it thoroughly once. Water sparingly until the first shoots emerge, as overwatering at this early stage can lead to rot. It can take two weeks or more for the first green sprouts to break through the soil.

Leaf and Stem Development

Once the first shoots appear, the plant enters a vigorous vegetative phase focused on producing its distinctive arrow-shaped leaves. The broad surface of these leaves captures sunlight for photosynthesis, converting light into chemical energy. This energy is stored in the rhizome to fuel future growth and flowers. To support this development, the plant requires consistent moisture and bright, indirect sunlight, so the soil should be kept evenly moist but not waterlogged.

Blooming and Flower Maturation

Following the period of active leaf growth, a specialized flower stalk, known as a peduncle, will emerge from the base of the plant. This stalk is thicker and more rigid than the leaf stems, designed to support the weight of the bloom. As the stalk reaches its full height, the most recognizable bloom begins to develop.

The colorful, funnel-shaped structure that is often mistaken for the flower is a modified leaf called a spathe. The spathe gradually unfurls to reveal the true flowers, which are tiny and located on a central, finger-like spike called the spadix. This entire bloom structure can last for several weeks, depending on the variety and growing conditions. A healthy, mature bloom will display rich, consistent color in its spathe and a fresh, bright yellow spadix at its center. The blooming period can last from six to twelve weeks.

Post-Bloom and Dormancy

After the vibrant spathe fades and the flower’s life cycle concludes, the Calla Lily begins to prepare for a necessary period of rest. This transition into dormancy is a natural and important part of its annual cycle, allowing the plant to conserve energy for the next growing season. The first signs of this phase are the yellowing and gradual dying back of the leaves and stems. As the foliage declines, it is a signal to reduce watering.

This resting phase allows the rhizome to recharge. For gardeners in colder climates (zones 7 and below), the rhizomes should be carefully lifted from the ground before the first hard frost. After digging them up, allow them to cure for a few days before storing them in a cool, dark place in a medium like peat moss or sawdust. In warmer regions (zones 8-10), the rhizomes can be left in the ground over winter, where they will remain dormant until warmer temperatures signal the start of a new growth cycle.