Pterocactus tuberosus is a geophyte cactus with huge tuberous roots under the soil ,with thin fragile blue-light to brownish-purple stems that breaks off easily. Many different forms exist. Root: Tuberous root, up to 8 cm thick, deeply set in the ground . All pterocacti have a tuberous root system from which the stems sprout and sprawl around.is absolutly winter resustant in UK . Best for greenhouse, garden in pot or rock garden, shelted in wet winter weader. Posting Parcel2Go small parcel, tracked. Probobly some stems will be broken in transport, but is Impossible to avoid.
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