Humans have been breeding plants for thousands of years. It's a matter of giving nature a helping hand. Plants also cross spontaneously in the wild, but it goes faster when people put the right plants together.
In the past, farmers crossed their own plants, but today that job is done by specialised breeding companies such as Enza Zaden. We can do this because we know exactly what plants need to be brought together to get the best result. Many people are under the mistaken impression that plant breeders genetically modify their products, but nothing could be further from the truth. In fact, genetic modification is strictly prohibited by law.
Breeding may sound easy, but you have to go a long way to achieve the desired result. At each stage, the breeder has to wait until the plant reproduces. And even if the breeder succeeds in producing a product, like a sweetgreen pepper, after a long series of generations, it is still not a given that the plant and the product are then ready for the market.
Whenever plants are crossed, there is always the risk of losing a beneficial property. And a product has to meet a huge number of requirements before it can be called suitable for the market. To name just a few, it has to be resistant to disease, so the grower does not have to spray with pesticides, and it has to produce a good yield to allow the grower to earn something back. And the product has to be attractive to the consumer, with, of course, taste being the key to success.
Luckily, Mother Nature has a treasure trove of diversity and variety, one that breeders have only tapped perhaps 10% of. With that in mind, you can expect new and exciting vegetables and fruits to arrive on the market in years to come.