Can store-bought papaya seeds produce viable plants?
Written by
Liu Xiaohui
Reviewed by
Prof. Martin Thorne, Ph.D.Growing papaya from seeds purchased at a grocery store begins with preparation. I have been successful in propagating ~80% of the seeds from a ‘Maradol' papaya using a method of soaking, fermenting, and drying them. Those seeds contain a gel coating that has germination inhibitors in it, and I have found that if these are not removed the germination rate drops below 20%.
Soaking Stage
- Submerge seeds in lukewarm water for 72 hours
- Change water every 12 hours to prevent mold
- Discard floating seeds (low viability)
Fermentation Process
- Transfer seeds to glass jar with 1-inch water
- Stir daily until gel dissolves (3-5 days)
- Add pinch of baking soda to soften coatings
Drying & Storage
- Pat dry on paper towels for 24 hours
- Store in labeled envelopes for 6-month viability
- Keep in cool, dark place (65°F/18°C ideal)
Hybrid varieties, such as 'Tainung,' generally express themselves in a mixed fashion. In my experiment in 2022 with 50 seeds from a store, 12 of them gave true-to-type plants. To obtain reliable varieties, it is best to select heirloom types, such as 'Solo,' whenever possible. Use labels for the seedlings until the fruit appears, to evaluate the genetic reliability.
Low Sprout Rates
- Re-soak seeds in 1% hydrogen peroxide solution
- Test soil pH (ideal 5.5-7)
- Maintain 85°F (29°C) soil temp
Fungal Growth
- Pre-treat seeds with 1:10 bleach soak for 5 minutes
- Use sterile seed-starting mix
- Increase air circulation
First true leaves will emerge in 14-21 days following planting day. I like to use biodegradable pots so I can transplant them without disturbing the roots. After they reach six inches about two weeks later, I begin acclimating seedlings to the outdoors. I gradually introduce them to the sun for 2 hours each day to strengthen the stems and acclimate them in a controlled way; this can help protect against shock.
Read the full article: How to Grow Papaya: 8 Essential Steps for Success
