Thanks to equisetum researcher Chad Husby, we are able to offer the true Equisetum giganteum. This collection of the rare fern relative hails from El Tabacal in Argentina's northern province of Salta, where it forms large stands of 10'+ tall, prehistoric-looking stalks. Imagine a giant green stake being plugged into an electrical outlet and you get the idea. Equisetum giganteum runs...no, it gallops, so do not plant it in the ground in warm climates. In containers, seal the drainage holes if escaping into the ground is possible. Equisetum giganteum is superb in a large container or submerged in a solid bottom ornamental pond. Of several accessions trialed, this is the only one that survived 15 degrees F in the ground.