What plant hardiness zone is Riehen

Riehen is located at Basel-Stadt (Basle-City) (BS), Switzerland.

Plant hardiness zone (winter frost zone or gardening zone) for Riehen is 6b by the USDA scale.

Coldest zone's winter temperature is −20.6 … −17.8 °C.

Plants of 6b USDA hardiness zone suitable for outdoor gardening and growing in this winter frost zone 6b USDA.

Alternative climatic zone of gardening for Riehen by UK RHS scale is H6.

Plants of H6 RHS hardiness zone suitable for outdoor gardening and growing in this winter frost zone H6 RHS.

Riehen @ wikipedia.

* The lowest temperature in Riehen was -18.8 °C on 04/02/2012.