One of the best things that you can do for a healthy, thick display of impatiens is to give them a good cut right away. This can be for potted containers, baskets, hanging pouches, beds or planters. It all works the same. Give them a good "hair" cut.
In our greenhouses we like to do this as soon as possible, once the plants get to be about 3 inches tall and start flowering. For us it is as soon as the plants are up past the tags that are in the packs.
Trimming them down helps to force them to branch out instead of stretching up towards the sky. They will grow much thicker and eventually become a healthy bed of sturdy flowers. They will go wider, rather than just vertical.
How do you do it? Well just like Walt Disney said "The way to get started is to quit talking and begin doing."
Now you will probably read all kinds of professional advice on taking care to clean the scissors to make sure that infection doesn't spread. That may be true and wise advice, but in the real greenhouse world where we only have 24 hours a day and need 25, we just start cutting.
And if you really want to have fun at it, fire up a hedge trimmer. You will be able to do a lot in a short time. Yes, it will look like a disaster and you will question yourself. But give it some time. They will grow back...healthier.
We were able to trim down 5 benches (22 flats per bench) in about 30 minutes using a hedge trimmer.
After you have trimmed back the foliage, run your fingers through and try to pick out as much of the cutting as possible. This helps to prevent any rot sitting down on the plant or in the soil. Usually they will be pretty wet, which makes it stick to your fingers and actually helps the process.
In only a couple weeks you will have a very nice and thick bed of impatiens that are ready for the season. Give them a good dose of Beat Your Neighbor fertilizer to speed up the growth.
If you are feeling a little skeptical it's okay. As I tell our greenhouse customers "trust me, they will grow back." And when they do our customers usually come back and tell me that they did it and had a beautiful bed of impatiens and have no hesitation the next time.
Check out our video on how to trim back leggy petunias: