Collect fruits from allspice trees that tend to have a large annual yield. Taking the seeds from these will result in more productive trees in the future. Soak the fruit in water for 24 hours and carefully pick out the seeds with a knife.
Plant the seeds in a nursery bed or pot, pressing them into the soil to a depth of 1/2 inch. Mulch them with 1/2 inch of dried leaves or straw and water regularly. The seeds should sprout within nine to 15 days.
Wait six to 10 months and transplant the seedlings to the orchard. Dig holes large enough to contain the potting soil surrounding the seedlings and plant them in groups of three at a distance of 20 feet. Give the young plants shade and irrigate them regularly. Mulch and manure the seedlings every couple weeks to a depth of 1/2 inch and pluck any weeds that spring up.