Is it too late? With heating mats & grow lights what kinda results can I expect? What should the room temp be? I normally start tomatoes & peppers in a cooler basement, but I could move upstairs if needed?

THANKS!!!

Dan

In your zone (if similiar to ours) it would be mid may to early june, which means that you would sow them mid to late march. Impatiens can grow pretty fast, and unless you can transplant into 3" square pots (4" round pots) then I recommend only starting them 6-8 weeks before planting out.
(if your basement is significantly below 60 deg F night temperatures you may need longer time).

Impatiens are not hard at all. The seeds can be quite small, but use the end of a moist tooth pick to gently transfer the seeds one by one to the pots. The seeds will stick to the moist wood and you can this way sow them one by one.

Press them lightly in to the surface, but do not cover.

Germination temperture is important. They require consistent 72-77 deg F in order to germinate. Lower than 72 deg F and you get vary irregular germination. above 78 deg F and the seeds enter a state called thermodormancy (basically it is too warm for the seeds to germinate).
The best way I have found to control the temperatures, is to cover the flats/pots/packs, etc with clear plastic (or plastic domes if you have them) and then adjust the fluorescent lights above the flats so they are 4-6" above. This will help heat up the temperatures under the covers (test with a cooking themometer to find out how warm the soil gets). You can also use heat mats if you have them.

Keep the lights on 24/7 until all seeds have germinated. This is required for uniform germination (also helps stabilize the temperatures)

In general we expect 70-75% germination success with our impatiens.

A special note on fertilizer:
- impatiens are light feeders, so only fertilize them with a dilute mixture and do so every 2nd or 3rd watering. But do make sure you fertilize starting from young seedlings (1st true leaf stage) as otherwise flowering will be delayed. Fertilizing the plants starting when they are very young can have great impact on the flowering later. Keep the fertilizer levels light, however, as they are light feeders.

About 3 weeks before you plan on setting them outdoors, pinch back the growing point. This will make for a bushier plant with more flowers (not so tall either).

It takes about 4 weeks from pinching to flowering, so pinching back 3 weeks before planting out (last week april, or early may depending on your target dates) will help you get flowers sooner and compact plants.

Good luck

When potting, make sure you do not compress the mixture, but fill the pots and then tap the side of the table to set the mixture settle. This will settle the soil, but retain air pockets. do not use your fingers to press the mixture into the pot, and do not place the mixture into the pots dry. it should be moist (but not soaked).

after filling the pots as above with moist mixture, plant your seeds on top, and put into a pan of water to wick up moisture from below. once the surface of the mixture starts to glisten and turn from dark brown to black, you can remove the pot/flats from the pan and put aside to drain.

Generally, if you water from below as described above, and keept the mixture moist, but not soaking wet then mold can be kept to a minimum.

some seed starting mixtures are worse than others and if you continue to experience problems, try to change to a new brand. I highly recommend sunshine#1 mix which has performed very well. another brand is GARDENERS.COM 's germination mix.