This chunk of spiky loveliness is one of the barrel cacti and is now unfortunately endangered in the wild. Naturally found in the deserts of east-central Mexico it is exceptionally well adapted for surviving long periods of drought and grows on very free draining volcanic slopes with little in the way of nutrients or soil.
Very architectural looking, it forms large, golden yellow spine covered globes usually up to 50cm in diameter with some specimens reaching up to 1 meter. Large plants are heavy and due to the spikes they can be quite a challenge to move so choose it’s final planting place very carefully. It is surprisingly cold resistant and said to be able to tolerate short spells down to -8c, but, it will only survive freezing temperatures if it is completely dry, both roots and outer barrel surface.

Position in full sun planting in a very sharply drained compost or soil with plenty of volcanic granules, grit, sharp sand, perlite or/and clay granules added. If growing in a pot use a clay/ terracotta pot rather than plastic and if you are going to try to grow this outside in the UK all year round it will need to be protected from the rain during the cooler months. Cold is not usually a problem but cold and wet will causing rotting. Despite not liking our winter wet they do grow much faster if watered regularly during warmer, dry, summer periods.

One person we know has a very large specimen growing outside down in the west country. He covers with a purpose built cold frame that is well ventilated to keep the excessive winter wet off the plant. He recommends covering the plant from early September so the soil around the plant dries out in the late summer sun and says the ventilation must be good, any humidity building up could cause rotting during the dark depths of winter. The cold frame is removed in late March to early April. We just move ours under the porch as it is still a manageable size at the moment, kept dry it has tolerated temperatures down to -5c with no damage.

Sent in a 10cm pot. 

Additional photos By André Karwath aka Aka - Own work, CC BY-SA 2.5, https://commons.wikimedia.org/w/index.php?curid=369777, By JayWalsh - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=30719836, By Alexisrael - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=32205639, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=550502, By AlixSaz - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=50240832.