Getting started -- Your Calla was grown in filtered light, not direct sun, so acclimate it to direct sun slowly. Start it in bright, indirect light the first week, then every few days, move it into more light, watching for wilting or burning.
Soil -- Use a well draining mix. I use a mix of 1 part coco fiber to 1 part perlite (use small- or medium-grade perlite, not coarse-grade). An alternate mix is 2 parts quality potting soil to 1 part perlite or coarse horticultural sand.
Transplant your plant to pot about 5-6 inches wide, or around a quart.
Watering -- This Calla likes consistently moist soil when it is not dormant. During warmer or sunnier weather, make sure the soil doesn't dry out. It reportedly can be grown in boggy conditions, but i haven't tried this.
Growing onward --
Light -- Give it bright light, but not strong sun. This Calla doesn't need as much direct sun as most Callas. It grows fine in bright shade with some dappled sunlight. If you choose to give it more sun, it will require more watering and feeding. Protect it from hot afternoon sun.
Climate -- The Hercules Calla prefers mild temperatures. In warmer climates, give it afternoon shade.
The plant tends to go dormant during the summer, and grows actively the rest of the year. The tubers are winter hardy to Zone 8 (20°F/-6°C) if planted deep. But since the plant prefers to grow throughout winter, it's best to grow it in a pot and bring it indoors before frost strikes.
Repotting -- Each time you repot it, bury it 1-2 inches (3-5 cm) deeper than before. After several years, it will need a very large pot, such as 10 gallons (40 liters) or more, depending on the size of the tuber.
Winter strategies -- If you bring it indoors over the winter, try to keep some or most of the leaves intact, if possible. Removing too many leaves may delay flowering.
Fertilizing -- Feed about every 2-3 months with an all-purpose fertilizer that contains micronutrients.
Bugs to watch for -- Spider mites (tiny "dots" under the leaves), Aphids (green ones are hard to see), snails/slugs. Try using insecticidal soap before using stronger remedies, since some may harm the plant.
If any questions or problems come up, feel free to email me.
Have fun growing it!
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