Keep in mind when planting that Viola Klose is thought of as hardy, so this plant will survive close to or on freezing temperatures.
By our calculations, you should look at sowing Viola Klose about 84 days before your last frost date.
Ensure that temperatures are mild and all chance of frost has passed before planting out, as Viola Klose is a hardy plant.
Also sold as x sylvestris, as a hybrid derived from nemerosa.