Impatiens are one of the most popular annuals in the entire world. There's nothing that makes them particularly suited for the Northeastern United States; they're simply popular everywhere. Impatiens are colorful, dependable, they bloom all summer, and they require very little maintenance.
Most notably, impatiens do very well in light shade. They can be planted in areas that other more light, dependent flowers can't. The average flower grows 6 to 24 inches (15 to 60 centimeters) tall, while the flower heads measure 1 to 2 inches (2.5 to 5 centimeters) across. They bloom in a wide assortment of colors including red, maroon, purple, pink, white, orange, salmon and mauve. Some have a contrasting color in the center of the bloom called an "eye," while others have a bi-color star pattern of white in the center that streaks out to the end of the petals. There's even a newer type of impatien, called a "picotee," that's edged in pink [source: Yardener].
Your local nursery will likely have a wide variety and selection of impatiens, but if you'd like to grow them yourself, you can do it. Start eight to 10 weeks before the last frost. Use a moistened seed-starting mix. It should be damp but not wet. Scatter the tiny seeds of the impatiens over the surface and pat them down lightly. Cover the container or flat with a clear plastic bag. Set them somewhere where they'll get plenty of indirect sunlight, sit back and relax.
In one to two weeks you should have sprouts. Remove the plastic cover and water regularly but not too often. When the seedlings have plenty of new leaves, they're ready to be transplanted. If your garden isn't ready for them, put them in individual cell pack containers until it is [source: Flower Gardening].
If you plant impatiens close together, they'll grow taller, so if you want them to spread out more, make sure to plant them 8 to 12 inches (20 to 30 centimeters) apart. Keep in mind that although they can be planted in the shade, you'll want to be careful about planting them too close to large trees. It's OK to do so, you'll just have to make sure they get enough water. Large tree roots tend to soak up all the moisture in the ground.
Lastly, learn about marigolds and why they're perfect for the Northeast.