Occasionally, germinated seeds may be found inside a grapefruit. But in most fruits, special chemicals or simply a high potassium concentration prevents this from happening. If seeds are to be collected from fresh fruit, they should be thoroughly washed and surface dried before planting. - Millet

Seed germination is a very interesting subject. People are still learning the many methods that plants have to ensure that their seed germinate at the right place, time and under the right conditions. Some years back I was given some books on the subject by my sister - Seed Germination Theory and Practice by Norman C. Deno. I found Professor Deno's book fasinating. I wondered if they were still available. A quick seach found this and other sites that indicate that they are:

http://theseedsite.co.uk/normdeno.html

Ned

Ned wrote:......." seed germinate at the right place, time and under the right conditions".............

SEEDS: This bring up seed stratification.

In order for seedlings to become well established during the most favorable season for growth, seeds of native plants from earth's temperate zones (places where cold winters are normal) must germinate in spring, after the last snows have melted. It would be wasteful for seedlings to start growth late in the year since none could survive winter. To avoid such an outcome, the seeds must be "stratified" before they can germinate, that is, they must be moistened and given an extended period of low temperatures. In nature, this happens in the course of the normal seasonal cycle. Seeds are produced in late summer, are moistened by autumn rains, chilled throughout the winter and are ready to germinate in the mild, sunny days of spring. Seeds possessing his requirement can be artificially stratified by placing them between layers of moist paper, in a refrigerator for a month or two. - Millet

SEEDS'

Why don't seeds taken from the same fruit all germinate at the
same time?

A batch of seeds taken from a single fruit, plant, or from the same species, may not germinate at the same time. As annoying as this may be to the horticulturist, in nature, staggered germination over several days, weeks (and for some species months or years) is advantageous to a species' survival. If every seed in a population germinated at the same time, the risk of having all seedling perish in a late frost or unseasonal drought, or eaten by an animal, is increased. While a seed is the stage in a plant's life cycle most resistant to environmental extremes, the young seedling plant is most vulnerable. The system of staggered germination maintains an emergency supply of viable seeds in the soil and is achieved by members of a seed population having different rates of after-ripening or variable rates of germination.. - Millet

We see this concept more than we would like in weeds! Barbara

It is amazing how many different techniques plants have to ensure survivability. Like Millet said, a number of species that contain multiple seed are programmed so that only one seed germinates per year. Barbara I believe I remember that sandspurs do this, which I suspose is one reason they are so hard to get rid of.

It will always stick in my mind that my Dad would pour boiling water over his okra seed, which hastened germination. I still wonder why that doesn’t kill the embryo!

Ned