Lilacs are deciduous shrubs that bear highly fragrant flowers, in shades of pink, purple, yellow and white in the spring. Because they are tolerant of a high degree of neglect they are great for the beginning gardener. After rooting your lilac be sure to plant it in an area that receives at least 6 hours of sun per day and keep the soil moist for its first year in the ground.
Take the cutting when new growth reaches 10 to 15 cm (4 to 6 inches) in length and cut it back to its point of origin. Wrap it immediately in a moist paper towel and place it in a plastic bag, sealed, where it will be shielded from the sun.
Fill the planting pots, to within 1.3 cm (1/2 inch) of the rim, with moist sand. Use your finger or a pencil to poke planting holes in the soil. Space the holes so that when the cuttings are inserted, they will not touch one another.
Remove the leaves from the cutting, with the exception of two at the top.
Dip the other end of the cutting in the rooting hormone so that at least two leaf nodes are covered in the powder. Tap the cutting on the side of the container to remove any excess hormone powder.
Set the heat mat to 23.9 degrees C (75 degrees F) and place it in an area that receives bright but filtered light.
Place the cuttings, hormone-tipped end down, into the prepared holes in the sand and pack more sand around the bottom of them. Water the cuttings until the excess water runs from the bottom of the pot.
Place the pot in a plastic bag, seal it and set it on the heat mat.
Check the soil every two days to make sure that it remains moist. Your lilac cuttings should root within eight weeks.
Acclimatatise the cuttings gradually to conditions outside the bag by uncovering them in the evening and covering them in the daytime. Gradually increase the amount of time that the cuttings are uncovered, over the course of two weeks.