- You Will Get 25 Seeds Of Easy Wave Blue Wave Pelleted Petunia Flower Seeds. - Watering: Light. - This type of petunia spread to about 35" and is great in hanging baskets and flower boxes flower size is about 2 1/2" across. - We place 5 of these in a 14" hanging basket and it makes it real full. - These do well in heat and in shade we also sell these in our greenhouse in single 4" pots and they do great for resale. - These are a great spreading petunia.