Why are the vines of my moon flower purple?

Question

I have moon flower plans, Ipomoea Alba. And I collected seeds form one and planted them. The seeds came up beautiful but with one problem, the vine and leaves have a purple color. The vines are completely a rich purple and the veins in the leaves are purple as well. I am wondering if they are some sort of hybrid or something, or perhaps there is something too rich, or lacking for that matter in the soil. Will they still produce the beautiful white flowers?

It was not labeled incorrectly because it was a seed from a moon flower plant I have already grown.

I purchased new seeds form Burpee and put them in the same soil, and THOSE vines are purple as well.

Answer 1

Glenn is correct. The "Alba" is a hybrid; seeds from hybrid plants very often do not appear the same as the plant you collected them from.
I've experienced this with the "Heavenly Blue" hybrid of convolulus (morning glory). It reseeded itself, and the following years all those seedlings produced nondescript purple flowers.
Best to purchase new plants or seeds year to year, Hon.

Answer 2

Is there a chance that the seed might not have been labeled correctly? The plant/vine you describe sounds similar to a purple hyacinth bean vine. You might just have to wait until it blooms to find your answer.

Answer 3

the hybrid=cultivar was the 'alba'=white. the seeds reverted to the parent plant. no