Germinating the seeds
These seeds sprout best when given a cold treatment first. The tips below explain the process.
When to plant -- Plant your seeds when you receive them for best results
Getting started -- Soak them in a cup of water for about 1 day (not more than 2 days).
Fill a small ziplock bag with a small amount of pre-moistened potting soil or coir fiber, and place the seeds inside. The mix should not be wet (no water on the bottom of the bag). Place the bag in the refrigerator and mark your calendar to remove them in 6 weeks. Pick the seeds out of the bag.
Soil -- Use a fast draining soil. A typical mix 1 part quality potting soil to 1 part coarse horticultural sand or perlite (use fine- or -medium grade perlite, not large chunks). An alternate mix is 1 part coir fiber to 2 parts perlite or coarse sand. Don't add lime to the mix, unless using peat moss instead of coir fiber.
You may use a single pot for all the seeds the first year. Use a pot at least 3 inches (8 cm) wide and 4 inches (10 cm) tall, with drainage holes. Fill the pots with your soil, place the seeds on top, and cover with 1/4 inch (7 mm) of soil. Add water until the soil is evenly moist (but not soggy).
Place the pot in area that stays between 45-75 degrees F (7-24 Celsius) during the day, and 40-65 degrees F (5-18 Celsius) at night. I recommend placing a minimum/maximum thermometer near the pots.
The seeds normally sprout at different times. Most of them should sprout approximately 2-3 months after removing them from the refrigerator. Sometimes they can take longer. Once they sprout, give them bright light, such as morning sun, filtered sun, or fluorescent or LED lighting. Protect them from strong afternoon sun.
Watering -- Keep the soil evenly moist (but not constantly saturated).
Fertilizing -- When they are a week old, give a very light dose of liquid fertilizer (about 1/8 strength), and repeat 2 weeks later. Hydroponic fertilizer works well for young seedlings, since it is easily absorbed and complete. After 3 months, you may switch to a general-purpose, granular fertilizer that contains micronutrients.
Climate -- It prefers temperatures below 80 degrees (27°C) with nights that are cool (below 65°F / 18°C) and frost-free. It might not thrive in areas that regularly get above 80 degrees from fall through spring, especially if nights are warm. It is said to be able to handle a light, brief frost, but i recommend protecting it from freezing temperatures. It prefers part sun, with protection from strong afternoon sun. Over about 40% humidity is best.
Support -- Give the shoots a vertical support to twine themselves around, such as thin sticks. The support doesn't need to be tall the first year. The second year you may use a tomato cage or similar support.
Dormancy -- The tubers normally go dormant in spring or summer, but it may happen at other times if growing them indoors under lights. If the leaves begin to turn yellow, the tuber may be preparing for dormancy, so reduce the watering to prevent rot. Once the shoots die back, dig up the tubers. If you find any seeds that didn't germinate, repeat the refrigeration process above - there is a good chance they will sprout.
Tips on repotting the tubers are here.
If any questions or problems come up, feel free to contact me.
Have fun growing them!
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