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Calla Lily Light Requirements [Quick Guide]

If regular watering, timely fertilizer application, and care fail to make any difference to your leggy Calla Lily, watch out for its light requirements. 

Chances are you might be over-shading the Calla Lily or exposing them past their light limit. 

Generally, the semi-evergreen Calla Lily thrives in 12-14 hours of bright indirect light, with an average light intensity of 2500 to 5000 lux. Light duration and intensity are subjected to slight change as per the plant’s growth stage and varieties. 

Besides, avoid light fluctuation to get your Calla Lily blooming throughout the growing season.

Do Calla Lillies like Full Sun or Shade?

Native to Southern Africa, many assume Calla Lily or Arum Lily to be heliophytes. But to our surprise, these plants prefer partial shade or filtered sunlight. 

Generally, Calla Lilies (Zantedeschia aethiopica) grow under bright, indirect light or partial shade, with a period of darkness to shift from photosynthesis to respiration. Besides, these plants can tolerate some full sun, especially during the morning and evening hours. 

You’ll not have a problem growing Calla Lilies from Zone 8 to Zone 10 since the zone barely goes beyond the plant’s light and environmental requirements.

These zones have mild winters and moderately bright summers, perfect for germination to seed production of the plant. 

A top angle photo of Calla Lily happily blooming under bright indirect light.
The size and color of the bloom indicate the health of the plant.

While the plant can still deal well with full sun in the cool summer areas below zone 7, dark winter following frosts and snowstorms is a big threat. 

The roots of Calla Lily freeze and loses its vegetation to harsh frost. Likewise, prolonged exposure to scorching sunlight leaves the plant dry and crumbly.

Signs of Excessive Light 

  • Yellowing of leaves, with brown blotches
  • Wilted curled leaves
  • Flowers start fading 
  • Dry and dehydrated ends that turn brittle
  • Eventually, the growth of the Calla Lily slows and stunts

Signs of Light Deprivation

  • Leaves appear pale or lighter in color than usual
  • Stretched and leggy plant longing for more light
  • Delayed or no flowering
  • Untimely bloom drop 
  • Weak and floppy stem

How Much Light Does A Calla Lily Need?

Calla Lily typically does best with 12-16 hours of sunlight with mediocre intensity, i.e., between 2500 to 5000 lux.

This mimics the long daylight hours of the growing season, suitable for the perennial Calla Lilies.

However, the light duration and intensity requirement for Calla Lily can vary depending on their growing conditions.

Germination Stage

The seeds of Calla Lily demand longer hours of light to break their seed coat and initiate the roots and shoots. 

Normally, 12-14 hours of sunlight precisely work for germinating Calla Lilies.

But the light has to be consistent, with an intensity of around 5,000 to 7,000 lux. 

Growth Phase

Once the Calla Lily seedling emerges, they still require 12-16 hours of sunlight for active growth. 

However, high-intensity light during growth can burn the leaves instead of doing good.

Young Calla Lily leaves are susceptible to dehydration, leading to yellow patches, scorched edges and stunted growth.

So, position your plant to receive a light intensity of approximately 2500 to 5000 lux. 

Flowering and Seed Formation

Blooming in Calla Lily beings in late summer or early fall when the days get shorter. 

Basically, Calla Lilies need a transition from normal growing conditions to induce flowering under 10-12 hours of light. Arum Lily blooms for 6 to 12 weeks in late spring to summer.

Further, reducing light duration, or shorter daylight hours, with the same light intensity as in the growth phase, stimulates seed formation.

A seed pod of Calla Lily about to burst.
Unripe seeds of Calla Lily resemble a hazelnut.

Adequate light helps attract pollinators like bees and beetles, along with providing energy for the growth and ripening of seeds. 

Upon consistent light and warmth, the mature seed pod releases spherical black to dark brown seed, ready for germination.

How To Maintain Calla Lily Light Requirements?

Here are a few tried and tested ways to maintain Calla Lily light requirements.

  • Positioned your Calla Lily plant in an area with partial shade, most preferably a shaded patio. Make sure not to plant them directly under tall trees, which could lead to light deprivation. 
  • Place them near a north or east-facing window for your indoor Calla Lily, facilitating ample morning and evening light. Use a sheer curtain if your window receives direct light incidence.
  • Monitor the light conditions and make adjustments accordingly. For zone 10 and 11, bring your plant indoors during peak hours. 
  • You may have to use artificial grow light to suffice the plant’s needs if you live in colder zones that do not receive enough natural light. LED grow lights, Fluorescent Grow lights and HID lights are the most commonly used ones.
  • Adjust the distance between the light source and Calla Lily to about 15 to 30 cm to avoid the risk of excessive heat. We recommend you follow the light’s instruction manual.

From Editorial Team

Provide Overall Care!

Besides the light, water your lilies twice a week and feed them some nitrogen-rich fertilizer once every fortnight during the active season.

Deadhead the spent flower to encourage new bloom. This helps you get big white tubular Calla Lilies.