Hello David, living in Jerusalem you might want to consider letting your tubers stay in ground over winter. If ground never freezes then they may well go for at least three seasons in a row. In my place I have tubers that have withstanded winter for three seasons (and longer). We have a Mediterranean climate like yours ( that is hot summers very dry and mild wetter winters, with perhaps five or six snowfalls durind winter). In origin dahlias of the Mexican plateau have wet summers and very dry winters. the exact oposite. The only risk may be if your soil is not sandy enough and winter water stays on your beds. Then your tubers might rot. Therefore you might want to lift your tubers only for multiplying your stock, or in case you want to ensure a particular cultivar. However if in the right growing condition then probably letting them rest where they grew the previous year/s might still be the best choice. All the best Arturo
