I've given up on growing Petunias by seed. Mine usually die,and if not, they grow upwards and do not branch out.
Even though I pinch them out. So I only buy them as seedlings.Make sure you have the right growing condtions for each plant.
Petunias are sunlovers. Impatiens are shade dwellers.
Impatiens are easily grown from cuttings. If you have a friend/neighbour that has them, ask for a few cuttings.

Petunias do sit with just the seed leaves for a week or two. You should notice the seed leaves getting wider, but you may not realise unless you have a freshly-germinated one to compare with. Then suddenly, you will notice that there are three seed leaves. Actually you now have a true leaf, but it looks just the same when it first appears. From this stage on they grow fairly fast and like some dilute fertiliser. Provide as much sun as possible and pinch regularly. They really do love the sun and will get leggy if they don't get enough.

Impatiens seed need fairly constant temperature and humidity to germinate. The maximum viable temperature range seems to be about 60F-85F, but really you should aim to keep the temperature between 70F and 75F night and day until the leaves open. A freshly-germinated seed will die if it gets cold at night, and this is a very common cause of "non-germination". Keep covered for maximum humidity until the first seeds appear and then start to let in a little air. Some sun is good, but they will wilt rapidly in hot sun.

Thank you for your information. I'm doubting that those petunias will proceed but we will see. Do you know if seed of petunias and impatiens get old quickly and then don't germinate?

Actually, I could not imagine anything easier than petunias. they germinate fast, and grow even faster.

The very tiny petunia seeds require warm soil, high humidity AND FERTILIZER to germinate and grow. I usually cover the flats with a plastic dome and keep the heat consistently 70-75 deg F for the 3-5 days it takes to germinate.

When they germinate, I DO NOT remove the dome immediately. I leave it on for a few days, and then crack it open. A few days later I will take it off during the days, but put in on at night. Only after about a week will I remove the dome entirely. The small seedlings are very sensitive, especially to cold temperatures/soil and low humidity. They can easily dessicate. They must be introduced to lower temperatures and humidity gradually.

When first sign of germination show, I usually put the flat back in a pan of water to wick up moisture again. At this time I use a diluted fertilizer (50 ppm calcium nitrate or calcium/potassium nitrate). Then after a week I start a regular fertilizer program.

Impatiens, as mentioned by shrubs-and-bulbs need consistent temperatures to germinate. This is how I handle them:

• Fill flats with damp seed starting mixture and tap the flats to settle the mixture without compressing it. Good air porosity in the flats are required.

• Surface sow the seeds and then cover with a very light layer of fine vermiculite. vermiculite help retain moisture around the seeds

• Put flats in pan of water to wick up moisture from below until surface of soil is glistening and turns black. Then remove and put aside to drain.

• Cover flats with plastic wrap or a plastic dome. Put on bottom heat, such as a heat mat with thermostat set to 75 deg F, or 1 foot below fluorescent lights which are on 24/7.

• Fluorescent lights are normally cool to the touch, but placed above a plastic enclosed flat, they tend to heat the inside. If placed about 8-12" above the top of the flats, they can be used as a 'heat' source. If you do not have a heatmat or thermostat, use the lights in this way, but keep them on 24/7. Do not let the temperatures vary from day to night. keep it consistent.

• When the seeds germinate, 10-12 days, crack the lid open for a few days. then remove the lid, and start a watering and fertilizing program. impatiens are light feeders

Kathy,
I could not agree more with Kenneth from New Jersey regarding Petunia seeds. I have always found them EXTREMELY easy to grow. The easiest seed I have ever sown is always the Petunia. And I always have problems with everything else. Hang in there...they will take off.

Denise