Papaya (Carica papaya) is a short-lived perennial growing to 30 ft (9.14 m) high. Its hollow, herbaceous stem is usually unbranched.
Two kinds of papayas are commonly grown. One has sweet, red or orange flesh, and the other has yellow flesh; in Australia, these are called "red papaya" and "yellow papaw", respectively. Either kind, picked green, is called a "green papaya."
The large-fruited, red-fleshed 'Maradol', 'Sunrise', and 'Caribbean Red' papayas often sold in US markets are commonly grown in Mexico and Belize.
Genetically altered papaya (including 'SunUp' and 'Rainbow') have some PRV DNA incorporated into the DNA of the plant are resistant to PRVs. This was so successful that by 2010, 80% of Hawaiian papaya plants were genetically modified.
The 'Solo' varieties are valued for productivity, uniform fruit shape and size, and excellent fruit quality. 'Solo' strains are predominantly self-pollinated and thus are highly inbred and uniform.
Three 'Solo'-type varieties are grown commercially in Hawaii:
- The most important is 'Kapoho', which has yellow-orange flesh and fruits that weigh 12 to 22 oz, considered an ideal size for export. 'Kapoho' is adapted to the Puna district of the island of Hawaii, where approximately 90 percent of the state's papayas are grown.
- 'Sunrise' variety, commercially grown primarily on Kauai, has reddish-orange flesh and larger fruit than 'Kapoho'. 'Sunrise' is grown and marketed on a large scale overseas, but in Hawaii its production and export are small compared to those of 'Kapoho'.
- 'Waimanalo' variety, which has yellow-orange flesh and somewhat larger fruit than other 'Solo' papayas, is grown and marketed almost entirely on Oahu.
Waimanalo Papaya is a yellow flesh solo papaya, which bears low to the ground initially. It is larger than the popular Sunrise papaya, weighing 22-32 ounces. Sunrise has a pink flesh.
This papaya was developed in 1960 and was publicly introduced in 1968. In temperate zones it can be cultivated in large pots and taken indoors during the winter. As the name suggests, it starts bearing when very short and continues for a good couple of years.
How to grow
Papaya is grown from seed. Dry seed may be stored for a year or more in airtight refrigerated containers. Fresh seeds will usually germinate in 10 to 14 days.
Seeds are sown either in containers or directly in the ground. Transplanting container-grown plants is usually limited to areas where there is dependable rainfall or supplemental irrigation. When direct-sowing, 10 to 15 seeds are sown 1/4 to 1/2 in (63 to 127 mm) deep in each planting hole.
Papaya grows well on many types of soil, but they must be adequately drained. Restricted soil drainage promotes root diseases.
Seeds are available here: http://www.ctahr.hawaii.edu/seed/seeds.asp
Papaya - Tropical Fruit Growers of South Florida.
Overview of crop improvement projects in Hawaii (PDF, 1982) http://buff.ly/1ZyEH7r
Papaya - Hedonista http://buff.ly/1Mv3YZt