There are quite a few fruit tree species that can be successfully propagated from seed. Seeds vary in the time they can be stored before planting, and the conditions they may require for storage. Some need to be planted immediately after collecting, and some need special treatment to induce germination.
The soil for germinating seeds or root cuttings should be porous, well aerated and well drained. A common mix is peat moss mixed with an equal amount of fine sand, perlite or pumice is excellent for growing rooted cuttings or seedlings.
If storing seeds, it is a good idea to sterilise them to help prevent fungus or mould forming. Sodium/Calcium Hypochlorite can be used, and is available as ordinary laundry bleach. It disinfects if used in a 10% solution with water. Soak the seed for 20 minutes and rinse thoroughly.
The following is a summary of how to propagate some species suitable to South East Queensland that are reasonably easy to try growing from seed.
Cherimoya and Pawpaw seeds can be stored for about 12 months, after drying to about half their original weight and kept at room temperature. Pre-soak the seeds for 24 hours, and expect germination within 3 weeks (up to 30 days for pawpaw).
Pitaya need the same treatment, but can be stored up to 3 years.
Jackfruit and Star Apple seed should be kept above 21° C and not allowed to dry out before planting. Soak for 24 hours before planting. They can be stored but are best planted as soon as possible.
White Sapote, Rollinias, Passion fruits, Jaboticaba, Cherry of the Rio Grande, Acerola, Pitomba and Wampi can all be stored for about 6 months and Figs and Macadamias for up to 2 years. For all these species, the seeds need to be dried to about three quarters of their harvested weight, and then kept at room temperature. Pre-soak before planting, and for White Sapote, remove the seed coat before pre-soaking. They will all germinate in 2 – 3 weeks.
Citrus - lemons, kumquat, grapefruit, tangerine and orange seeds can all be stored for about a year by drying them to about three quarters of their weight. They need to be pre-soaked and will germinate in about 2 – 3 weeks (up to 30 days for lemons).
Persimmon seeds are easy to germinate, as long as you do not allow the seed to dry out before planting, and keep above 21° C. They should germinate in 2 – 3 weeks.
Loquat seeds are a little more difficult. They can only be stored for a few days, and to germinate, need to be soaked first for 24 hours, then chilled for 3- 40 days at about 40C (a cold fridge).
Lychee, persimmon, canistel and mango seeds should not be allowed to dry out before planting. Keep them moist, and plant as soon as possible, although mango seeds can be kept for a couple of months and canistel up to 6 months. Remove mango seeds shell carefully. All of these might take up to 3 - 4 weeks to germinate.
The Mulberries are interesting to try germinating. Black, red and white varieties all need the same treatment – the seeds need to be scarified by rubbing them on sandpaper, and then soaked for 24 hours and stored moist for one or more seasons in the natural environment. They will take 2-3 weeks to germinate.