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Squeeze the bottom of the pot your lavender plant is in. This helps loosen the lavender and its dirt ball from the smaller pot. Tilt the lavender sideways and pull gently on the plant's base. With the loosening of the previous step, the lavender plant should ease out of its old pot. The dirt should be solid enough that it feels like it will come out in one chunk if handled gently. Handle your pot-less lavender gently to avoid breaking the dirt and damaging the roots as well as the foliage above the dirt. Now you're ready to pot your lavender plant in the new pot! Nestle it into the dirt that is already in the pot for security. The base of the plant should sit 3-inches below the rim of the pot. Gently break the surface of the lavender dirt ball with your fingers to release some of the roots. Root binding happens when a plant has been in a small pot too long and the roots rival the dirt for space. This makes the dirt hard and unless the dirt and roots are loosened, the roots will not expand in their new pot and the plant will soon die. Most potted plants won't be root bound, but it's a good idea to loosen up the roots and dirt a little to ensure the roots get a healthy start. Fill it only up to the top of the dirt ball around the lavender plant's roots. Don't pack the soil around the Lavender plant. The soil needs to stay loose for effective drainage. Sprinkle the fertilizer on the soil and then scratch the fertilizer into the soil with a fork. Timed-release fertilizer can be found at any gardening or farm store and will release fertilizer as the plant is watered. An example of a timed-release pellet fertilizer is alfalfa pellets. They are organic and contain Triacontanol, which is a growth stimulant. Some soils come with fertilizers like alfalfa pellets already mixed in, so you may not need to do this. Turkey grits or white landscaping pebbles work best for mulching lavenders. Lay the mulch on the soil in a 2-inch thick layer up to the base of the plant. This mulch is great for preventing rot in the roots and stems of the plants. The white color of turkey grits and white landscaping pebbles will reflect sunlight back to the plant which will stimulate growth. The mulch will also encourage air circulation and quick drainage. These materials are inexpensive and can be found at farm and pet stores and some garden stores.
Remove the Lavender plant from its current pot. Place the lavender plant in the center of the pot. Fill the rest of the pot with your potting mix. Spread a half cup timed-release fertilizer over your potting soil. Mulch your lavender plant.