What happened to momma's seed planted in the yard?

Isabel plants the seeds that were in her mother's jar. Isabel does this at the very end of chapter 13. She does not know what the seeds will grow into; therefore, she isn't overly excited at doing it; however, she does find the action of planting those seeds a bit cathartic.

I did not know what they would grow into, but planting them deep in the cool dirt was a comfort.

Readers hear about those seeds a few chapters later. They have sprouted, but the plant is still too small for Isabel to know what it is. The next time we hear about the seeds and growing plants is in chapter 33. This is a big let down. Isabel had forgotten to care for the plants, and they died in an overnight freeze. Isabel does her best to gather some seeds that are in the flowers of the dead plants, and she wraps those seeds up in a cloth.