Growing Healthy Petunias
- 1). Plant petunias in an area that receives at least six hours of sunlight a day. Choose areas that are well-drained and not prone to standing water, or use a container with at least one drainage hole in the bottom.
- 2). Water petunias once weekly, moistening the soil to a 6- to 8-inch depth. Irrigate twice weekly during hot, dry weather. Water pots when the top 1 inch of soil begins to feel dry, every one to two days in most cases.
- 3). Fertilize petunias with an 8-8-8 or 10-10-10 analysis fertilizer at planting, applying 2 lbs. for every 100 square feet of bed or at the rate recommended for containers. Begin additional fertilizer treatments two months after planting, applying a balanced soluble fertilizer to both beds and containers every two to three weeks at the label-recommended rate.
- 4). Spread a 2-inch layer of mulch over the bed and around the petunia plants. Mulch helps keep the soil moist and cool while also stopping most weed growth.
- 5). Pinch back petunias at mid-season if they begin looking overgrown or unhealthy. Pinch off up to half of each growing stem. Pinching encourages new, lateral growth, which results in fuller, bushier plants.
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