As well as holding information on the cultural heritage of their heirloom seeds – gathered by specialist seed historians – Seed Savers Exchange is working with a network of 700 gardeners across the US to help it learn which varieties might best adapt to different environments. Those gardeners grow seeds that the organisation would like more information on, then report back on aspects like germination rate, growth habit, and how the plants are doing in their climate. “These are people that are all across the country, so it allows us to be able to start to see what sort of environments some of these crops are thriving in,” says Mike Bollinger, executive director of Seed Savers Exchange.
Seed saving also opens up possibilities to create new varieties that are better adapted to local conditions, or which have other selling points.
Take the German pink tomato, one of the heirloom varieties brought to the US in 1883 by the grandfather of Seed Savers Exchange co-founder Diane Ott Whealy. If you grow several plants of that one variety in your garden, there’ll be slight variations between all of them. One might produce its tomatoes slightly earlier, whereas another might make bigger or tastier fruits. By choosing which plants to save seed from, you can select for those plants with the traits that you want to preserve. “It continues to be that same German pink tomato, but you’re adapting for the environment that you’re in, the traits that you like,” says Bollinger.
You can also go one step further, allowing different varieties of a plant with traits you’d like to combine to cross-pollinate, then saving seeds from plants that have those desirable traits. Repeating this process year after year is how Oklahoma farmer Carl Barnes cultivated the rainbow-coloured glass gem corn that became an internet sensation in 2012.
This process of adaptation is also key when it comes to finding crops that will be resilient in the face of extreme weather and climate change. Instead of relying on scientists to create new varieties in the laboratory using seeds pulled from cold storage, cultivation offers constant opportunities for existing varieties to adapt to whatever is thrown at them. “In situ conservation is really important because then the plants are continually adapting to the real conditions, not laboratory conditions,” says Stenner.
In the Potato Park, research by farmers has shown that the ideal conditions for different potato varieties are moving up the mountain to cooler altitudes as average temperatures rise. But they can only do this for so long.
“Because they’re so high already, they’re running out of space to keep doing that,” says Stenner. As one of the community elders said: “You can’t grow potatoes in the sky”. So, the farmers are instead nudging the potatoes towards re-adapting to lower altitudes.
“There’s so much built into a lot of these open-pollinated varieties already, it’s a matter of being able to start growing these out and using the inherent genetics in them,” says Bollinger. “You can navigate through that with the intelligence that is already built in… as opposed to trying to use technology to create something that doesn’t exist.”
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