Once the toads and frogs find your pond in the spring and spawn, the tadpoles will really attract garters. We have 3 ponds and they all have attracted garters, frog, and toads, especially the big koi pond but even the little one in the front (2000-300 gallons only) I have seen garters at. Build the water and they will come, lol. Good luck
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Jeff Benfer
gartersnakemorph.com