QuestionsHow to growFlowersBorder Perennial FlowersTropaeolum speciosum 0 Vote Up Vote Down m o asked 8 years ago When is the best time and how do you sow seeds to obtain the best germination success of tropelium speciousm 1 Answers 0 Vote Up Vote Down Gerry Daly Staff answered 6 years ago Sow them fresh and about 2cm deep ina post of soil/peat compst mix. Often they germinate roots withut showing at the surface initially.