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 Weather Station

Products > Agave 'Risner Bill'
Agave 'Risner Bill' - Hardy Cow Horn Agave

Note: This plant is not currently for sale. This is an archive page preserved for informational use.  

Habit and Cultural Information
Category: Succulent
Family: Agavaceae (now Asparagaceae)
Origin: Mexico (North America)
Evergreen: Yes
Bloomtime: Infrequent
Parentage: (Agave colorata x A. bovicornuta)
Height: 2-3 feet
Width: 3-5 feet
Exposure: Full Sun
Summer Dry: Yes
Irrigation (H2O Info): Low Water Needs
Winter Hardiness: 10-15 F
Agave 'Risner Bill' (Hardy Cow Horn Agave) - A medium sized rosette forming succulent to 3 feet tall with 2 foot long gray-green broad leaves that have prominent mammillate margins bearing reddish teeth that make distinctive bud prints on th inner leaves. Plant in full sun. Little irrigation required. Hardy to 15 to 20 degrees F. This plant was received as Agave colorata x A. bovicornuta from Mark Sitter of B&B Cactus Farm in Tucson and upon further investigation we have found out that the cross was made by Gene Joseph of Plants for the Southwest in Tucson who named the cross Agave 'Risner Bill'. The plant looks intermediary between the parent species with grayer leaves than Agave bovicornuta has and also lacking its characteristic cow horn-like teeth along the margin but also growing less upright in a fuller rosette of greener leaves than one expects from Agave colorata. The plant has proven to withstand considerably more cold in Tucson than Agave bovicornuta and so was a good replacement for it in colder areas. Gene Joseph also made the reverse cross (A. bovicornuta x A. colorata) that he named 'Bill Risner'.  The information on this page is based on the research that we have conducted about this plant in the San Marcos Growers library, from what we have found on reliable online sources, as well as from observations made of our crops of this plant growing in the nursery and of plants growing in the nursery's garden and those in other gardens where we may have observed it. We also have incorporated comments received from others and welcome getting feedback from those who may have additional information, particularly if this information includes cultural information that would aid others in growing Agave 'Risner Bill'.