Cut a piece of bamboo skewer to fit the length of the stem. A toothpick will provide an effective splint for a seeding or smaller stem.
Stand the stem upright at the point of the break and place the skewer or toothpick flush against the broken section.
Attach the splint to the stem by wrapping both loosely in electrical tape. Do not wrap the stem too tightly because it will cause further damage and not allow the stem to transport nutrients to the blooms or vegetables effectively.
Monitor the stem for the next one to two weeks. Eventually, the stem will begin to repair itself. Once the stem will support its own weight, remove the splint and tape.