Giant Spear Lily
Getting started -- Soak the seeds in water for 6-8 hours (not more than 12 hours). Take small containers approximately 3" deep and fill each to within 3/4" of the top with soil. You can use ordinary potting soil, provided that it is well-draining. Water the soil so that it is uniformly moist, but not soggy, and then place 1 seed on tip. Cover with about 1/4" of soil and water lightly. Move them to a cool spot (about 65-75 degrees) with some light, and make sure the soil doesn't dry out. You can keep maintain moisture by placing them in a propagation dome or in a bag. Just open it every day or two to let in fresh air. Most should sprout within 2 months, although allow up to 4 months for any slow ones.
Once they sprout, move them to morning sun, and gradually give them more sun over the next couple of months. Water whenever the top inch of soil feels dry, but avoid keeping the soil soggy. Some mid-day shade might be needed in warmer areas.
Long-term care: Try to keep the soil about halfway moist most of the time. I recommend using a moisture meter probe to monitor the soil moisture. You can buy this at garden and hardware stores for about $4. Simply stick the probe in the soil at the level where the roots are, and water whenever the needle is about 3 or 4 on a scale of 10. Avoid letting the soil completely dry out, but don't let it stay soggy either. And of course don't let the pots sit in a tray of water. If your tap water is questionable, use bottled spring water or rainwater.
Feeding -- Once the plants are 2 months old, feed every 1-2 months, using an ordinary complete fertilizer at 1/2 the recommended dose. Unlike some Australian plants, this one can handle phosphorous, but make sure the fertilizer has an equal or greater amount of nitrogen than phosphorous. Don't overfeed your plants - it will not speed their growth and may end up poisoning them.
Repot your plants to a larger container whenever the roots start circling around the bottom of the container or poke out of the holes. As they grow larger over the coming years, repot them to larger containers as necessary. If you grow them indoors and the air has less than 50% humidity, use a room humidifier to raise it up. The plants are said to handle several degrees of frost, although it's best to give them overhead protection from frost.
If you have any questions, feel free to email me.
Strange Wonderful Things