Can I be certain seeds will be fertile and grow true to the parent pl
Nothing is certain in life or gardening, but it's perfectly acceptable to ask the trader if (s)he has ever successfully grown the seeds you are requesting. You can also post questions about germinating and growing specific seeds on the 'Growing From Seed' forum here at GardenWeb. Be aware that gardeners may not know the exact origins of all the plants they grow and can make honest mistakes as to whether those plants can be duplicated by means of the seed they produce. Even though some seeds may not grow into plants identical to the parent plants, you can still end up with wonderful new additions to your garden.