The first thing you need to do is to harvest maple seeds. This is perhaps the easiest thing to do when growing maple trees. A fully ripe maple fruit falls from the tree, ideally in the mid of autumn. In the ripening season, you will be able to find plenty of maple seeds scattered all around and under a maple tree. Harvest as many seeds as you need.
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You will need to stratify all the maple seeds, unless you are planning to grow a silver or red maple tree in which case you plant the seeds without stratification. To stratify the maple seeds, prepare a mixture of equal parts of sand and peat moss. Fill this mixture in a perforated plastic Ziploc bag and then sow the maple seeds in the sand-peat moss mixture. Store the plastic Ziploc bag in a refrigerator for a period of 90 to 120 days while maintaining the refrigerator temperature between 33 and 41 degrees Fahrenheit.
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When the stratification period ends, you will have to wait until the end of frost. You have two options. Either you can store the stratified seeds in a brown paper bag or you can plant them in 6-inch pots. Whatever option you choose, make sure that you do not leave the seeds in frost.
In late spring, it is time to sow the maple seeds. In a pot, prepare a mixture of peat moss, organic compost, coarse sand and vermiculite and sow the maple seeds in this mixture, one seed in each pot. Regularly water the pot but make sure you let the mixture to dry completely before watering it again.
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When the maple seeds sprout, you must keep them in 50 percent shade. Install an artificial shaded if necessary. When the seedlings have grown approximately 4 inches in height, carefully transplant them outside. Do not forget to water the seedlings at regular intervals, letting the ground in which they are sown to dry before watering it again.
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