Pruning and dividing bee balm are two things that run hand-in-hand. If you find that your bee balm plant is just too big in the middle of its blooming season, you can prune it back, but the following spring you will have to divide it. These perennial flowers attract bees, so be careful when you care for your bee balm plant.
Step 1 - Assess Your Bee Balm
Come autumn, look at your bee balm plant. If it was just the right size this year, it will most likely be too large next year. If it was smaller than you would have liked, you do not have to divide it.
Step 2 - Prune the Plant
Even if your plant was too small, you still should prune it. Cut off all of the branches as low as you can. Bee balm is extremely hardy, so it can withstand even the most severe pruning. This will only help it to grow better later on.
Complete the pruning as close to the main stem as possible, so that it leaves only stubs about 1 inch thick. When you are done with the pruning, you will probably have a tree that resembles a stem with some stubs where branches had been.
At this point, if you have to divide the plant, you can go get your shovel and get ready to do just that. Being a strong plant, it will survive the dividing at this stage.
Step 3 - Divide the Bee Balm
If your plant needs to be divided, drive your shovel down hard into the center of the root ball. You should cut off between a third and a half of the root. Make this motion carefully and cleanly in a single stroke. Be careful not to rip the taproot in half. If you want the plant to divide properly, you must keep the root and the crown intact in each part that you make.
Step 4 - Plant the Divisions
Now you are ready to plant your divisions elsewhere in your garden. Divisions will have the same plant and flora as the parent bee balm, wherever you plant them. Plant them just as you did with the original—with the root completely in the soil and the stem above the level of the ground—and give them a good amount of water.
For the next few days, you should water the plants copiously and regularly. Bee balm doesn’t take much time to gain root and start growing. However, till the time you perceive any growth, you should keep watering the plant.
You are all finished. Now you can use your bee balm to attract birds and butterflies, and to repel moths from your clothes when you harvest and dry it.