Answer: I think what you are growing are Datura, also known as Brugmansia, although the plant might also be moonflower. Ipomoea alba, otherwise known as Moonflowers, are so called because they bloom in the evening. They have large 4 to 6 inch fragrant, white or pink flowers on twining vines. The flowers open quickly in the evening and last through the night, remaining open until touched by the morning sun. Moonflowers are annuals. You can collect the seeds to replant next spring. On the other hand, Datura produces a seed pod that looks like a spiny ball (like a castor bean seed pod). This sounds more like what you have described. Datura flowers in the evening. You might do a websearch on both of these plants to see which looks more like the one you're growing. Enjoy!
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