"True Blue" Impatiens
Germinating the seeds
Getting started -- This Impatiens sprouts best after a 4 week cold period ("stratification"). The tips below explain the process.
When to plant - Plant your seeds when you receive them for best results.
Soil - It likes moist, well-draining soil that's high in organic matter. A typical mix is 2 parts potting soil to 1 part perlite or coarse horticultural sand. An alternate mix is 3 parts perlite to 2 parts coir fiber, with some slow-release fertilizer mixed in.
Fill small containers or cups that have drainage holes and place a seed on top. Sprinkle a very thin layer of your soil on top - just enough to barely cover the seeds. Add water until the soil is evenly moist (but not completely saturated).
Next, place the pots in a spot that stays between 35 and 50 degrees F (2-10°C) for at least 10 hours a day, for 4 weeks. You may put them in the refrigerator - just seal them in a bag or container first.
Mark your calendar to remove them after 4 weeks, then remove them from their bag or container and keep them in a spot that is between 60 and 75 degrees F (16-24°C). Avoid letting them get above 78 degrees F (26°C). I recommend placing a minimum/maximum thermometer near the pots.
Ensure that the surface soil doesn't dry out. An easy way to maintain moisture is with a plastic container or bag - just leave it open a crack to allow fresh air in. Place the seeds in a bright spot. A fluorescent or LED bulb kept 5 inches (12 cm) away provides the right amount of light.
The seeds can start germinating at various times. Some may start germinating in 3-4 weeks while others may take 3-4 months. Once they sprout, move them to a bright spot out of direct sun.
Climate -- The plant grows best between 50 and 85 degrees F (10-29°C), with nights that are cool. There are several reports of it tolerating warmer conditions with warm nights, but it should still be considered experimental in warm climates. The plant needs protection from freezing temperatures. Indoors, if the air is dry, consider using an ultrasonic humidifier.
Lighting -- This Impatiens does best in filtered light. Strong sun may cause burning or wilting.
Watering -- Try to keep the soil moist, but not soggy, most of the time. Ensure that it doesn't dry out.
Repotting -- Move your seedlings to a larger pot when they are about 6 weeks old. Transplant gently to avoid damaging the roots. Adult plants can be grown in 1-2 gallon (4-8 liter) pots.
Fertilizing -- Your Impatiens likes average amounts of fertilizer. Feed about every 2 months using a general-purpose fertilizer that has micronutrients. Liquid fertilizer is best for young seedlings the first 4 weeks.
Pests to watch for -- Watch for pests that can affect your other plants - possibly aphids, scale (little brown disks on the stems), spider mites, whitefly, mealy bugs.
If you have any questions, feel free to email me.
Have fun growing them!
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