Disgustedorite's Gem Seed AU

Gem Seed AU is an open (free to use) AU created by HohkiTEC. It's a partial AU that can be applied on top of any other AU.

In Gem Seed AU, Gems have or used to have the ability to reproduce on their own. It differs from the more popular Gem Egg AU in that the Gems drop seeds which grow in the ground just like ones planted by injectors, rather than laying eggs.

Description
In this AU, prior to the invention of injectors Gems reproduced naturally through mating much like life on Earth. After mating, each parent drops 18-24 seeds into holes or cracks in the ground. These eventually grow into Gems who emerge at full size, like those planted by injectors.

As Gems have no differing biological sexes, both parents carry and later drop the seeds. Because it takes a very long time for the seeds to grow and they emerge at full size anyway, Gem parents do not stick around to look after them.

Gem seeds will not grow in any environment that doesn't match their Gem type. For example, a Quartz seed can only grow where a Quartz kindergarten could be built, and a Ruby seed can only grow where a Ruby kindergarten could be built. Seeds produced by parents of differing Gem-types might be able to grow in the same environments as either of the parents, but are usually nonviable in any natural environment.

Internally, the bits responsible for producing seeds and the means to fertilize them resemble the organ-like innards of injectors. In fact, this AU assumes that injectors were made based off of them.

After the invention of injectors, the ability to reproduce naturally was suppressed in newly-made Gems, but an individual Gem may reactivate it by her own choice. In the event of a major disaster preventing further Gem production by artificial means, the Diamonds can sing a song that reactivates the ability to reproduce naturally in all Gems within range.

Compatibility
Any two Gems can mate and produce viable seeds, but the further apart they are chemically, the less likely it is that they could grow in any natural environment. A chart will be added soon showing a theoretical "family tree" indicating how closely-related different kinds of Gems are, and thus the likelihood there is of them producing viable seeds with one another.

Trivia

 * HohkiTEC created this AU after becoming frustrated by the severe lack of any kind of Gem reproductive AU or headcanon that was even remotely close to what was already described in canon.
 * Nearly every aspect of this AU is built from descriptions of how Kindergartens and injectors work, particularly information included in the Classroom Gems short "How Are Gems Made" and the official book "Guide To The Crystal Gems".