The hard spring frosts, which affected the Greater Poland region between 4th and 6th May 2011, broke records not only due to the drop in temperature, but also in the damage caused. The article covers the frost damage caused in those few days to trees and shrubs at the Adam Mickiewicz University Botanic Garden in Poznań. The damage is presented on a scale of 1–10. Trees and shrubs from the boreal climatic zone and those from mountainous regions suffered most. Those plants that start their growing season late were also badly damaged, including those with a hollow core, or those with a lamellate or spongy pith. Some plants were so severely damaged by the spring frosts that they were not strong enough to begin the growing season again, and died.