Creating a flow garden in outdoor plant boxes is a fantastic way to add color, texture, and movement to your outdoor space. The key to a successful flow garden lies in selecting plants that thrive in containers while offering continuous blooms and visual interest. Here are some of the best plants to consider:

1. Petunias: These vibrant annuals come in a variety of colors and are perfect for cascading over the edges of plant boxes, creating a flowing effect.

2. Calibrachoa (Million Bells): Similar to petunias but with smaller blooms, these plants are ideal for adding a dense, colorful display.

3. Verbena: Known for its long-lasting blooms, verbena is a great choice for attracting pollinators and adding height to your flow garden.

4. Bacopa: This trailing plant produces delicate white or blue flowers, perfect for softening the edges of your plant boxes.

5. Lobelia: With its striking blue or purple flowers, lobelia adds a cool-toned contrast to warmer-colored blooms.

For a dynamic flow garden, mix trailing plants with upright varieties like salvia or dianthus to create layers of color and texture. Ensure your plant boxes have proper drainage and use high-quality potting soil to keep your plants healthy. Regular deadheading and fertilizing will prolong blooming and maintain the garden's vibrant appeal.

By carefully selecting and combining these plants, you can create a stunning flow garden that transforms your outdoor plant boxes into a living work of art.