How to start clivia seeds
I'm no expert on clivias, but I have been growing them since 2004, and have learned a technique for growing them from seed that seems to work very well. I'd like to share it here and invite others to share their methods or comment on mine.
If the seeds are more than a week or two old, clean them with water and mild dish detergent and then rinse well. Soak them over night in clean water mixed 4 to 1 with hydrogen peroxide. (If the seeds are very fresh, you can skip this first step.)
Prepare about a cup of long fiber sphagnum moss by soaking it in warm water and then squeezing dry. (New Zealand moss is best.) Add the moss to a small ZipLoc bag along with the seeds. You want the moss moist like a squeezed out sponge with no extra water in the bag. Close the baggie and place in a warm place (75-85 degrees F) in a light, but not sunny, location where you won't forget to look at it regularly. Open the bag to smell the moss and dampen if necessary every two or three days. It should smell fresh, not moldy. If you see any sign of fungi or algae growing inside the baggie, remove the seeds, wash them with dilute hydrogen peroxide or mild liquid soap and plant them in an open container.
The seeds take anywhere from two to six weeks to sprout. The first thing you will see is the root pushing out from a little dimpled area on the seed. This is called the radicle. This will slowly get longer and eventually, the first bit of green will let you know the first leaf is going to form. This is when I remove the seed from the baggie and put it into potting mix. If the little radicle gets to be more than 1/2 inch long without any green showing, you can move it at that time as well.
The next step is to prepare a small 2- or 3-inch pot with drainage holes filled with a sterile quick draining potting mix. If you have a high quality soilless mix like ProMix or MetroMix, that will work. Or you could use seed starting mix. Some people use a 50/50 mixture of peat moss and perlite. I recommend adding extra perlite to any formula to ensure that the mix is fast draining. Water the pot and let it drain. You can plant all the seeds in the same pot if they are at least an inch apart. Make an indentation in the soil surface and set your clivia seed in it so the little root is pointing down. Don't bury the seed; just gently press it into the soil. Place the pot under fluorescent lights or in a bright window. Water from the bottom when the soil surface feels dry. Keep the seedling growing in a warm place with bright light, preferably for 16 hours a day.
Many people have trouble with clivia seedlings developing fungi infections. You can do a Google search or search on GardenWeb and find at least a dozen different techniques for starting seeds, mostly based on preventing the many diseases that can kill clivias. Whatever method you use, when you are ready to put the seedlings in a pot, be sure to keep the environment as clean as possible. The little seed will stay attached to the seedling for three months or so, feeding it everything it needs during that time. Don't fertilize or use an organic potting mix with things like manure, compost or garden soil in it during this time.
After about three months, or when the seed falls off the seedling, begin using a complete, balanced fertilizer with trace elements at half strength about once a week. Clivia seedlings grow very slowly in the beginning. It can take up to six months for the seed to form a second leaf. Once the seedling is growing well, you can transplant it into a slightly larger pot with fresh, fast-draining potting mix. For the first two to three years of growth, keep the plant growing in these conditions year around. Once the plant has 12 leaves, it is mature and capable of flowering given the right conditions.
I've uploaded a close up of a seed that is starting to form its first leaf. This was taken about a month after I started trying to sprout it. I had just removed it from a baggie of damp sphagnum moss to put it in potting mix.