Germinating the seeds
When to plant -- Plant your seeds when you receive them for best germination.
Getting started -- You may plant each seed in individual, small containers, or all together in a single container. Either way, use pots with drainage holes
For soil, use a well draining mix. A typical mix is 2 parts potting soil to 1 part perlite or
coarse sand. An alternate mix is 1 perlite to 1 part coir fiber or
peat moss, with some slow-release fertilizer
Until the seeds sprout, ensure that the surface soil always stays moist. If you enclose the pots to maintain moisture, leave it open a crack to allow some fresh air in, to prevent stem rot later on. You may need to drip a few drops of water over the seeds every day to keep the seeds moist.
The ideal temperature for germination is between 65 to 77 degrees F (18-25°C). A little cooler at night is ok. Avoid letting them get above 80° F (27°C). I recommend placing a minimum/maximum thermometer near the pots.
A fluorescent or LED bulb kept 4 inches (10 cm) away provides the right amount of
light. Protect from direct sun.
Fertilizing -- For the first month, it's best to give weekly feedings of
a very dilute (1/8
strength) liquid fertilizer.
is perfect for young seedlings, since it is easily absorbed and complete.
Once they are 1 month old, you may switch to a granular fertilizer if you wish.
Use one that contains micronutrients, and follow the dosage on the package.
The pots you use does not
need to be very tall but they should be wide, since the tubers mostly grow
sideways. As the plant grows larger, its tubers increase in size very
rapidly, so occasionally dig down to the tuber to determine when it is time to
repot. Failure to check on the tubers may lead to broken pots!
Humidity - If grown indoors, and your room humidity is under 40%, consider using an ultrasonic room humidifier, which you can buy inexpensively at places like Home Depot and thrift shops.
Pruning -- Pruning isn't necessary. This Impatiens usually makes a single main stem with few side branches. Pruning the top will encourage the side branches to grow fuller.
Dormancy care -- Indoors, the plants may stay evergreen all year, but outdoors it tends to go dormant in winter if temperatures go below about 40° F (5°C). If it does go dormant, ensure that the soil does not dry out completely during the winter. If you pull the bulbs up to separate them, place them back into lightly-moist soil, so they do not dry out. The bulbs are fairly rot-proof, but avoid letting the soil get too wet while dormant. It tends to come out of dormancy around April here in California.
Outdoors, the dormant tubers are hardy down the low-20s (-5°C) if planted deep and kept dry, although it's probably best to bring the pot indoors for the winter.
Pests to watch for -- Scale (little brown disks on the stems), aphids, spider mites (tiny "dots" under the leaves), whitefly.
If you have any questions, feel free to email me.
Strange Wonderful Things