Calochortus

This is probably the most diverse genus of bulbs growing in the western hemisphere. Calochortus are found in western North America, Mexico, and south to Guatemala. Although some have felt that it has warranted its own family, Calochortaceae, currently more authorities are including it in Liliaceae. The greatest concentration of species is found in California.

There are two good sources of information on Calochortus. The first is: Frank Callahan, "The Genus Calochortus," in McGary, 2001 found listed in References. The second is Calochortus, Gerritsen and Parsons, 2007 found listed in References. The authors of this book, Mary Gerritsen and Ron Parsons, have provided a lot of pictures and information that can be found on the species Calochortus wiki pages. In addition, you can view photographs on Mary's Picasa Gallery of Calochortus species and natural hybrids. Hugh MacDonald, former head of the Calochortus Society, has posted a large collection of photos in his Gallery of Calochortus (note that the links in his gallery do not work in Firefox, Chrome, and Safari). Some other information found on those wiki pages was taken with permission from the issues of Mariposa, the newsletter of the Calochortus Society.

Although Calochortus have a reputation as being difficult to grow, raising them from seed is manageable given the right conditions. Here are some guidelines from PBS list members:

• Seeds of Calochortus can last about 5-6 years but longevity may be extended if stored in the refrigerator (Michael Mace).
• In mediterranean climates, sow the seeds thinly in the fall in a well-drained mix. Good seeds will germinate very well but in crowded conditions seedlings will damp off very quickly. In California, it is never recommended to sow seeds in spring because they will not have enough time to build up bulb mass to last through the summer (Diana Chapman, Michael Mace).
• Mary Sue Ittner found in her wet northern California garden that sowing in late January meant she lost fewer seedlings to damping off.
• Sow the seeds and keep the pots outdoors where they get some cooler temperatures of about 40-70F (4-21C). Some sources suggest that prolonged higher temperatures can reduce germination.
• Sow the seeds outside and cover the seeds with a thick (half inch at least) layer of coarse decomposed granite (Diana Chapman) although some members feel the tiny seeds could have trouble pushing up through that much weight. They say covering the seeds with a 1/4-1/2" (1/2-1cm) of seedling mix is sufficient (Nhu Nguyen, Michael Mace).
• In areas with cold winters such as the UK, it is recommended that seeds be sown in spring so that the seedlings can benefit from decent light and warmth.
• Some growers in too cold winters and too hot summers have success growing seedlings under lights indoors.
• Seeds will germinate in less than 6 weeks, although some may not germinate until the following year.
• Once germinated, fertilize the seedlings with a low nitrogen, high phosphorous fertilizer. Fertilization will greatly increase the size of both seedlings and adult bulbs.
• Stop watering when seedlings start to yellow and allow them to go into a completely dry dormancy (Nhu Nguyen).
• Mexican species should be sown in spring and kept moist in summer.
• Mary Gerritsen's book, Calochortus, provides a list of species which need to be stratified before sowing.

You can find much more detailed informationon Calochortus culture, including advice on soils, pots, and watering schedules, here: How to grow Calochortus

Photos of representatives of the different subsections of Marion Ownbey's section Calochortus

Photos of representatives of the different subsections of Marion Ownbey's section Mariposa

Photos of representatives of the different subsections of Marion Ownbey's section Cyclobothra

The diversity of Calochortus species is reflected in the wide range of English common names applied to the flowers. Unfortunately, the common names do not align cleanly with the scientific subsections above. But here is a quick guide:

• Mariposa Tulips are large, upright, bowl-shaped flowers, often with intricate color markings and sometimes hairs. Calochortus venustus is an example.
• Pussy Ears or Cat's Ears are small, upright flowers with very hairy tepals. Calochortus tolmiei is an example.
• Globe Tulips or Fairy Lanterns are nodding, roughly spherical flowers. Calochortus amabilis is an example.
• Star Tulips are small, upright flowers that resemble miniature Mariposas, although they usually have fewer markings. Calochortus uniflorus is an example.

For more information and pictures of the species, click on the pages listed below or on the species name in the table below.

Calochortus species A-B - Calochortus species C-D - Calochortus species E-Lo - Calochortus species Lu-N - Calochortus species O-R - Calochortus species S - Calochortus species T-U - Calochortus species V-Z - Calochortus hybrids - Calochortus index

Calochortus species A-B - Calochortus species C-D - Calochortus species E-Lo - Calochortus species Lu-N - Calochortus species O-R - Calochortus species S - Calochortus species T-U - Calochortus species V-Z - Calochortus hybrids - Calochortus index