How to Propagate the Centaurea Cineraria With a Root Division
- 1). Water the parent Centaurea cineraria plant deeply the day before taking root divisions from it. Water it with the hose on low for five to 10 minutes or to a depth of 5 inches.
- 2). Find a 12-square-inch portion of foliage near the edge of the Centaurea cineraria plant. Insert a garden trowel 4 inches deep into the soil 1/4-inch from the edge of the plant. Work the trowel around the 12-square-inch area until it is completely separated from the parent plant.
- 3). Work the garden trowel under the Centaurea cineraria plant at a depth of 4 inches. Slide the blade of the trowel around beneath the root mat to separate it from the soil.
- 4). Lift the 12-inch portion of the Centaurea cineraria plant from the ground. Fill in the hole left by removing the division with standard garden soil.
- 5). Place the Centaurea cineraria division on a flat surface. Cut it into six equal portions using heavy-duty shears. Keep the divisions in a shaded spot while preparing the growing bed.
- 6). Prepare a bed for the Centaurea cineraria divisions. Select a site with identical growing conditions to where the parent plant was growing. Work the soil to a depth of 6 inches with a cultivating fork. Turn and aerate the soil with the fork to loosen it.
- 7). Plant the Centaurea cineraria divisions so the base of the foliage is flush with the surface of the soil. Avoid making the plant lower than the soil around it because water will pool around the roots and cause them to rot.
- 8). Water the Centaurea cineraria divisions to a depth of 2 inches or 4 inches if the weather is very hot. Water to 1 inch every three days for the first two weeks. Decrease water to 1 inch every five to seven days from then on. Roots will emerge within five days of planting.
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