The Cold-Rating Data Base

Disclaimer and Data Usefulness

Data accumulated in the CRDB is based on field observations of individual growers and collectors. These observations may not represent the actual cold-hardiness for plants of the same species due to the complex interaction of various other factors not necessarily listed in the CRDB.

Take the hardiness data as an approximate; if you are more of a risk taker you can try a particular species at even lower temperatures. But make sure to take care of other factors (see the Zone Enhancer Guide) to increase the chances of survival or, if you want to stay on the safe side plant only species with a much lower temperature rating than you will ever experience.

The CRDB presents the lowest degree reported on a species which might be based on data from a grower or collector who perfectly optimized conditions for the species and who took extreme care of enhancing microclimatic conditions. However, observations which involve artificial heat will not be included. Please be aware of the likelyhood that a plant die at even higher temperatures than the one listed in the CRDB.