Plant	Hardy?	Survival from winter -01 .. -02 / No snow cover, min temp -21°C
R. wardii hybrid ‘Goldbukett’	-24° C	No damage.
R. calophytum hybrid ‘Caramba’	-24° C	10 % of leaves were partly brown. Otherwise, looks good!
R. ‘Hachmann’s Charmant’	-26° C	No damage.
R. ‘Pearce’s American Beauty’	-26° C	No damage.
R. ‘Calsap’	-26° C	No damage.
R. carolinianum hybrid ‘Manitou’	-26° C	No damage.
R. dauricum hybrid ‘April Gem’	-26° C	No damage.
R. ‘Matterhorn’	-26° C	No damage.
R. yakushimanum ‘Ken Janeck’	-26° C	No damage.
R decorum hybrid ‘Dagmar’	-27° C	95 % of the leaves were brown! However, seems to survive.
R. impeditum hybrid ‘Blumiria’	-27° C	No damage.
R. yakushimanum hybrid ‘Sonatine’	-27° C	5 % of leaves were partly brown, but no damage to flower buds.
R yakushimanum hybrid ‘Falling Snow’	-28° C	No damage.
R. smirnowii hybrid ‘Gradito’	-28° C	No damage.
R. Exbury Azalea ‘Gibraltar’	-25° C ?	No damage.
R. Knapp-Hill Azalea ‘Goldtopas’	-25° C ?	No damage.
R. prinophyllum ‘Golden Lights’	-36° C	No damage.

The plants were planted in spring 2001 and all had a good growth during the summer.
The winter hardiness is from Hachmann Sortimentskatalog 2001 - 2005 when given, otherwise from other sources.

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