Keep in mind when planting that Violet is thought of as tender, so remember to wait until your soil is warm and the night time temperature is well above freezing before moving outside. Violet requires a soil ph of 6.6 - 7.5 meaning it does best in weakly acidic soil - weakly alkaline soil.
Growing Violet from seed
By our calculations, you should look at sowing Violet about 35 days before your last frost date.
Transplanting Violet
Ensure that temperatures are mild and all chance of frost has passed before planting out, as Violet is a tender plant.