Germinating the seeds
» Your seeds should be planted the day you receive them
» They might sprout during shipping, so be careful when opening the packet, to avoid damaging the root.
Getting started -- Rinse the seeds in plain water.
If you have germinated other Clivia seeds before, you may use the same technique that worked for you. The method below works well for me.
You may plant them all in a single, small container, since they will be removed once they sprout. Use pots about 3 inches (8 cm) tall with drainage holes. Fill with perlite. Use small- or medium-size perlite, not large chunks.
Push the seeds into the surface so the top of the seed is even with the surface. If the seed has a dark spot or line, place that sideways. Space the seeds about 1 inch (3 cm) from each other. Water the perlite thoroughly. Make sure the top of the seed is visible (but not sticking out of the perlite).
The optimal germination temperature is about 66-77° F (19-25°C) during the day. A little cooler at night is ok. Avoid letting them get above 80° F (27°C) for prolonged periods. I recommend placing a minimum/maximum thermometer near the pots.
Ensure that the perlite always stays moist. If you enclose the pot in a plastic container or bag to maintain moisture, leave it open slightly for fresh air to enter. You may need to drip some water over the seeds each day to keep them moist.
Keep them in bright light out of direct sun. An LED or fluorescent lamp placed 4 inches (10 cm) away provides the right amount of light (See: "Growing indoors with LED lights").
The seeds will first grow a root, followed by a leaf about 2-4 weeks later. They tend to sprout at different times, with most of them sprouting between 1 and 2 months. Occasionally they can take up to 6 months, so as long as the seeds are firm and white, don't give up on them! After they sprout, continue giving bright light, with no direct sun for the first 3 months.
Once the first leaf appears, gently dig up the seed and gently repot it into the soil mix described in the next paragraph. Use a container at least 5 inches (13 cm) tall, with drainage holes. I prefer to use 1 pot per seedling, but you may use a communal pot - just place the seedlings 3 inches apart (7 cm). Continue keeping them in moderate temperatures the first 6 months.
Soil -- Use a loose, well-draining medium. A typical mix is 1 part small orchid bark, 1 part quality potting soil and 1 part perlite or coarse horticultural sand. Or use 2 parts potting soil to 3 parts perlite. Don't add lime to the mix. After filling the pots, don't compress the soil.
Watering - The plants like to have their roots kept moist, so aim to keep the soil evenly moistened, but not constantly saturated. Don't let it dry out completely, and don't let the pots sit in a tray of water.
If your tap water is very "hard", meaning high in minerals, you might need to use bottled water or rain water if your plants seem stressed.
Fertilizing -- The first 2 months, i recommend feeding every 10-14 days with a small amount of dilute (1/8 strength) liquid fertilizer. Hydroponic fertilizer is ideal for young seedlings, since it is easily absorbed and contains all essential nutrients. After 2 months, you may switch to a granular fertilizer that contains micronutrients, following the dosage on the package. Or continue feeding with some liquid fertilizer at 1/8 strength every 10-14 days.
Climate -- Clivia robusta has similar requirements to the common Clivia. Ideal temperatures are below 85 degrees F (29°C), with nights that are cool. It's best to protect them from all frost, especially the first 2 years. Older plants can survive a few degrees of frost, but the leaves will be damaged. Bright shade or filtered sun is best. Avoid strong sun exposure. Over about 40% humidity is best.
Re-potting -- Once the plants have 4 leaves, they may be moved to a 1 quart (1 liter) pot, and then to a 1 gallon (4 liter) pot 6 months later. After 2 years, move them to a 5 gallon (20 liter) pot, where they may stay until they flower.
Flowering -- It's likely that this species needs cool nights in winter to trigger flower, like the common Clivia. So once the plants are 3 years old, try to expose them to temperatures between 40 and 60° F (4-15°C) for about half the day for 4 to 8 weeks in autumn. Reduce watering slightly in cooler temperatures, but don't let the soil dry out.
If you have any questions, feel free to contact me.
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