Petunias grow as either perennials or annuals, depending on their growing site and care. Plants grown in optimal conditions will flourish the following year and will not die off. Being one of the most sought-after flowering plants that gardeners add to their landscapes, creating new plants through cuttings is desirable. Though a little fussier than most cuttings, with the right timing and care, petunia cuttings should be ready for spring planting in the garden. You will then be able to enjoy your favorite petunia in multiple locations.
Sterilize your pruning shears in a solution of equal parts bleach and water. Dip the shear's blades into the mix to remove any bacteria attached to them. You then will not transport any diseases to your petunia cutting.
Take your cuttings in late fall, so they will have time to root and establish themselves in their containers before placing in the ground.
Snip off a 5- to 6-inch stem of the petunia plant, right above a leaf eye. Remove any flowers or buds, as well as all the leaves except the top four.
Fill a 4-inch container with a very lightweight mixture of potting mix that has vermiculite in it. Be sure the potting mix is light and airy and is not heavy or the cutting will rot. The potting mix must drain very well. Stick your finger into the soil and make a hole approximately 2 inches deep.
Pour a small amount of rooting hormone out on a paper towel or plate. Dip the end of the petunia cutting into the hormone and shake off any excess. Do not dip the cutting directly into the hormone container, or it can become contaminated.
Stick the end of the petunia cutting into the hole in the container. Fill the hole with soil and lightly pack down with your finger so the cutting stands upright.
Water the container well. Keep the soil lightly moist, but not soggy. Place the cutting in an area that receives high light and is warm.
Fertilize the cutting with a water-soluble 10-10-10 fertilizer at a rate of half strength, 2 weeks after planting. Continue to fertilize once per week. Plant the cutting into a flower bed in spring.