03/11/2026
Why we need to leave stems for 2 years, not just 1
Take advantage of this warm spell to trim last year's stems!
MYTH: “To support stem-nesting bees, gardeners should wait until spring temperatures are consistently above 50 degrees before trimming last year's stems. Pruning earlier will harm the bees overwintering inside the stems"
FACT: "To support stem-nesting bees, gardeners should ensure that last year's stems are trimmed back (to 8-24") by early spring, creating nest sites *before* the first bees of the season emerge."
Stem-nesting bees select dead stems from the previous year for nest sites. Last year's stems do not contain stem nesting bees, and trimming them before the season creates habitat. The bees that emerged during the 2025 season would be nesting and overwintering in stems that grew in prior years, and those stalks should not be disturbed. Pruned stems will fall away naturally in subsequent years with no additional cutting required, and new growth will cover the stem stubble.
For more info on supporting overwintering wildlife, check out our blog post on garden clean up! https://mtcubacenter.org/tips-for-fall-garden-clean-up/
