How to Reproduce Arborvitae Plants
- 1). Gather seed cones that drop from arborvitae trees in the fall. Shake the seeds from the seed cones or extract them with tweezers, if necessary.
- 2). Line a plastic bag with damp paper towels and place the seeds in the bag. Seal the plastic bag and store it in a refrigerator for at least two months. Arborvitae seeds require this cold stratification period to germinate.
- 3). Fill a seed tray with potting soil. Remove the arborvitae seeds from the plastic bag and plant them in the tray at a depth of about 1/2 inch. Keep the seed tray indoors in a sunny window. Water the seed tray with 1 inch of water per week so the soil remains moist but not wet.
- 4). Select an outside permanent planting site with fertile soil and good drainage. Remove the arborvitae seedlings from the seed tray after the last expected frost when they reach a height of at least 6 inches. Place the seedlings in the planting site at the same level as they were in the seed tray.
- 5). Water the arborvitae seedlings with 1 to 2 inches of water per week during the first growing season. Apply a 2-to-3-inch layer of mulch around the tree during the following spring. Keep the mulch several inches away from the trunk.
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