Growing Lilac from Cuttings
Propagating lilac bushes from cuttings is tricky, but definitely not impossible. Take cuttings of lilac bushes from tender new growth in late spring or early summer. Mature growth is less likely to root. Take several cuttings to increase your chance of success. Take cuttings in the morning when the weather is cool and the plant is well-hydrated. Cut 4- to 6-inch lengths (10-15 cm.) of tender, new growth. Strip the bottom leaves from the cuttings, leaving two to three leaves at the top. Roots will emerge from the nodes – the points where the leaves were attached to the stem. Fill a pot with potting soil, sand and perlite. Moisten the mixture lightly, then use a stick or your pinky finger to make a planting hole in the mixture. Dip the bottom of the cutting in rooting hormone and plant it in the hole, then pat the potting mix lightly around the base of the cutting so it stands up straight. You can plant several cuttings in the same pot, as long as they leaves aren’t touching. You can also plant cuttings in celled nursery trays. Place the pot in a warm location such as the top of a refrigerator. Bright light isn’t needed at this time. Water the cuttings daily, or as often as needed to keep the potting mix slightly moist but never soggy. You can cover the pot with a clear plastic bag to provide a humid environment, but be sure to open the bag occasionally or poke a few holes in the plastic to provide air circulation; otherwise, the cuttings are likely to rot. Watch for the cutting to root in one to two months – usually indicated by the appearance of healthy, new growth. At this point, move the pot to bright, indirect light and allow the potting mix to dry slightly between watering. Let the lilacs mature until the roots are well established, then move them to their permanent outdoor location.
Can You Root Lilac Cuttings in Water?
Some plants develop roots quickly in a glass of water on a sunny windowsill, but this practice isn’t usually recommended for lilacs. If you want to give it a try, take a cutting from a healthy lilac and place the stem in a clear or amber glass or jar with 1 to 2 inches (3-5 cm.) of water. Be sure to strip the leaves from the part of the stem that will be in the water to keep the cutting from rotting. Add fresh water as needed. If the stem develops roots, plant the cutting in a pot and let it mature until the young plant is well established, then move it outdoors.