Germinating the seeds
Your seeds should be planted immediately when received
Getting started -- Soak your seeds in a cup of water for 18-24 hours (not more than 48 hours).
Soil -- The Hercules Calla is adaptable to most soils, but it prefers well-draining soil. A typical mix is 2 or 3 parts potting soil to 1 to 2 parts perlite.
Use small pots or cups that have drainage holes. Fill them to within an inch (2 cm) of the top with soil, put a seed on top, cover with 1/2 inch (1 cm) of soil. Add water until the soil is evenly moist (but not soggy). Try to keep the soil this moist the entire time.
Until the seeds sprout, try to keep the pots between 60-77 degrees F (15-25 Celsius). Avoid letting them get above 80 degrees F (27 C). I recommend placing a minimum/maximum thermometer near the pots.
They should start to sprout within 1-2 months, however allow up to 3 months for any slow ones.
Light -- Once they sprout, give them bright light, such as morning sun, filtered sun, or fluorescent lighting. This Calla doesn't need as much direct sun as most Callas. Protect them from strong afternoon sun.
Watering -- This Calla likes consistently moist soil. During warmer or sunnier weather, make sure the soil doesn't dry out. Avoid keeping the soil soggy all the time however.
Climate -- It prefers cooler temperatures away from hot sun. It flowers best with winter temperatures between about 40 and 65°F (4-18°C), and summer temperatures between about 60 and 80°F (15-27°C). In warmer conditions, keep it out of hot sun.
Repotting -- When the seedlings are 3-4 months old, they may transferred to bigger pots, and continue potting up as they grow bigger. Older plants may be grown in the ground in mild-winter areas. If you keep them in pots, use as big a container as possible for older plants, to ensure the largest flower size. Each time you repot, bury it under an inch or two (2-5 cm) more soil. A mature bulb should be under about 5-8 inches (12-20 cm) of soil.
Winter strategies -- 'Hercules' is root hardy to Zone 8. Protect it from all frost if you want the leaves to survive through the winter. This Calla usually doesn't go dormant in winter, like other Callas. If you bring it indoors over the winter, try to keep some or most of the leaves intact, if possible. Removing the leaves may delay flowering.
Fertilizing -- Feed about every 2-3 months with an all-purpose fertilizer that contains micronutrients. Cut back on the feedings if your plant goes through a dormant period.
Bugs to watch for -- Spider mites (tiny "dots" under the leaves), Aphids (green ones are hard to see), snails/slugs.
If any questions or problems come up, feel free to email me.
Have fun growing them!
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