Answer: Convolvulus as a group are aggressive self seeders. I am not familiar with that particular variety, so if it is a hybrid be aware that it may not produce viable seed, or the offspring may not match the parents. In either case, it will make seed whether it is planted in a container or in the ground. If you wish to grow it in the garden from seed, simply harvest some seeds as they reach maturity and sprinkle them where you would like them to be next year.
Good luck with your seeds!
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