Explain why fresh seeds of some plants from temperate zones?

Saying the seeds are from temperate zones means they're from areas where there are definite cold and warm seasons (and usually rainy and dry seasons as well, athough the maximum precipitation can come with either temperature).

It wouldn't benefit the plant as a species to have its seeds germinate when it would be too cold, or too dry from the seeds to grow and survive.  So some seeds must have a period of cold temperatures before the seeds will germinate.

Other seeds have a very hard seed coat that doesn't allow the seed to germinate until the coat is weakened.  This can be done by a freeze/thaw cycle for some, but others need for the coat to be weakened by breaking or scratching it.  In nature, this can be done by animals through swallowing the seeds and having the coat partly dissolved by their stomach acids, minor grinding by their teeth, or being trampled by larger animals with hard hooves.  Then the seed is able to absorb moisture to begin the germination process.