The Genus Menodora
Bull’s Balls
Family: Oleaceae
The two species likely to be for sale in Arizona are Menodora scabra and M. longiflora. These are broom-like wirely perennials growing up to about 2’ tall, often only about a foot tall. These two species are very similar except M. longiflora has longer flower (the tubes behind the petals). The yellow aromatic flowers appear in warm weather.
Another species, the spiny bull’s balls (Menodora) is a spinescent shrub with very different, but still aromatic white flowers. It is found in desert habitat in California, Nevada, Utah and Arizona.
Full sun, moderate water with good drainage, hardy to at least 15°F.
The nectar rich, highly aromatic, yellow flowers loved by moths and butterflies. There is a New Mexican and Texan species (Menodora longiflora) which has a slightly larger flower that is sometimes available, it is slightly more cold hardy.
Menodora as a genus has a long history of medicinal use in most of the places the genus occurs.
There are 26 species of Menodora found in the temperate Americas and in southern Africa. The genus name, Menodora, comes from Greek menos, force or courage, and doron, gift, alluding to medicinal or nutritional qualities; the species scabra means rough or scurfy. The other species, longiflora, means long-flowered.
Menodora scabra is found on arid slopes, from 1,500-7,500 ft. in southern California, southern Utah, Arizona, southern Colorado; New Mexico, southern Texas; south to northern Mexico. Menodora longiflora is found in similar conditions, but in Texas, New Mexico and south into central Mexico.
Flower detail of Menodora scabra with the shorter corolla (flower), photo by Patrick Alexander, SEINET
Long-flowered Bull's Balls (Menodora longiflora) has a longer corolla (flower), photo by Ron Chang, iNaturalist
The seed capsules is what lends the name "bull's balls". Both species have similar capsules. This is M. scabra, photo by Liz Makings, SEINET
Spiny Bull's Balls (Monodora spinescens) can get to 3' tall and a bit wider. It is found in desert habitat in California, Nevada, Utah and Arizona. Photo by glittergravel, iNaturalist