Growing the seeds
Plant your seeds immediately when received.
Cherimoya seeds sometimes have trouble kicking off their outer shell, so to help it along, i take a large toenail clipper, and clip off about 1/8 inch (2 mm) at several points around the seed, so that you can partially see inside at several points. It isn't necessary to clip all the way around. If the edges are too thick to clip, try cracking the seed lightly with a nutcracker. The embryo is well-protected inside and usually doesn't mind the treatment.
Next, soak the seeds in room temperature water for about 24 hours (not more than 48). Use a well-draining soil mix, such as 2 parts quality potting soil to 1 part perlite or coarse horticultural sand.
Cherimoya seedlings need a tall container, otherwise the taproot can grow deformed, which stunts their growth. Bury them 3/4 inch (2 cm) deep in a deep container (at least 4-5 inches / 10-12 cm tall), and water until the soil is moist (but not soggy). Keep them about 65-77 degrees F (18-25 C). Avoid letting them get above 80° F (27°C) for prolonged periods. I recommend placing a minimum/maximum thermometer near the pots. Give them some air circulation.
They should sprout in about 4-6 weeks. Start them with filtered sun or 1-2 hours of direct sun, but protect from strong afternoon sun. Water as needed to keep the soil moist (but not constantly saturated). Once the seedlings have 3 leaves, gently transplant to a taller pot, and move them into bright shade for a week. You can move them outside if temperatures are mild. Gradually increase the amount of sun they get a little each day, until they have 1/2 day sun after 4-5 months. Cherimoyas prefer partial shade while young.
Remember to protect your plants from frost, especially when young, as they will not survive temperatures under 27-31 degrees F (-2 degrees C).
For more info on growing Cherimoya, see : http://www.crfg.org/pubs/ff/cherimoya.html
If you have any questions, feel free to contact me.
Best of luck!
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