Propagation by Seeds
The fruit of Capparis sandwichiana is a oval orange berry about 1 1/2 inch long. The small reddish brown seeds are embedded in the smelly orange fruit pulp.
Boche and Moss recoomend colleting the fruit before it is completely ripened in order to avoid insect damage. Green fruits that are almost mature can be ripened in a sealed plastic bag. The fruits will become orange when they are ripe which takes about 7 to 10 days. Remove the seeds from the soft, ripe fruit by mashing them by hand in a bowl of water. Pour off the pulp and any seeds that float. Boche recommends planting the seeds as soon as they are removed from the fruit. Plant the seeds in a well-drained mix such as 3 parts perlite to 1 part sand or sterile potting mix.
Mature seeds germinate readily. In his germination studies, Obata found that untreated seeds of Capparis sandwichiana had germination rates ranging from 30 to 75%. Lilleeng-Rosenberger obtained a germination rate of 70% when fresh seeds were soaked in cold water for 4 days. (Boche 1994; Lilleeng-Rosenberger 1996; NTBG 1994; Obata 1967)
Boche, Kenneth, and Barrie Moss. 1994. Unpublished paper on miscellaneous native species. Paper read at Propagation and Culture of Hawaiian Native Plants Workshop, at Naniloa Hotel, Hilo, Hawaii.
Lilleeng-Rosenberger, Kerin. 1996. Plant propagation notebook. Unpublished materials: National Tropical Botanical Garden.
Mew, Randal K. T. 1987. Cultivation and propagation of selected coastal plants at the Waikiki Aquarium. Newsletter of the Hawaiian Botanical Society 26 (2):27-32.
National Tropical Botanical Garden (NTBG). 1994. Mai'a pilo. In Native Hawaiian plant information sheets. Lawai, Kauai: Hawaii Plant Conservation Center. National Tropical Botanical Garden. Unpublished internal papers.
Obata, John K. 1967. Seed germination in native Hawaiian plants. Newsletter of the Hawaiian Botanical Society 6 (3):13-20.
Wagner, Warren L., Darrel R. Herbst, and S. H. Sohmer. 1990. Manual of the flowering plants of Hawai'i. 2 vols., Bishop Museum Special Publication 83. Honolulu: University of Hawaii Press and Bishop Museum Press. p. 492-493.