How to Propagate a Mandevilla Plant
- 1). Fill a large container with a mixture of half commercial potting soil and half coarse sand. Any container is fine as long as it has adequate drainage. Set the container aside while you prepare the mandevilla stem cuttings.
- 2). Cut a 4-to-6 inch tip from a healthy mandevilla stem. Use a sharp knife or pruners that have been wiped with rubbing alcohol to remove any bacteria. Take three or four cuttings in case some of them don't root successfully.
- 3). Strip the leaves from the bottom half of the mandevilla stem. Roll the bottom inch of the stem in powdered rooting hormone.
- 4). Plant the stem in the potting soil, tamping the soil gently around the stem. As you plant, try not to rub off too much of the rooting hormone. Several stems can be planted in the same container as long as the leaves aren't touching.
- 5). Mist the soil lightly so that it is damp but not soggy. Place the container in a clear plastic bag and secure the bag with a rubber band. Place the bag in bright light, but avoid hot, sunny windows as sun magnified through the plastic can be hot enough to scorch the cuttings.
- 6). Check the bag daily. If you don't see beads of moisture inside the bag, open the bag and mist the soil. Don't allow the soil to dry out, and don't allow it to become waterlogged, which can rot the stems.
- 7). Check for roots in two to three months, or if you see new growth. Carefully remove one stem from the soil with an old spoon. If the stem hasn't rooted, continue to check on the roots' progress every three to four weeks. When the roots are at least 2 inches long, open the bag for about a week so the plant can acclimate to the drier, cooler air outside of the bag. replant each stem in an individual 4-to-6 inch container.
- 8). Re-plant each stem in an individual 4-to-6 inch container. Place the newly-rooted mandevilla vines in a sunny window and keep the soil moist.
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