Creating a small herb garden in urban planter boxes is a rewarding way to bring fresh flavors to your kitchen. The key to success lies largely in providing adequate depth for healthy root growth. For most popular culinary herbs, a planter box depth of 6 to 12 inches (15 to 30 cm) is sufficient.
This range accommodates the majority of herbs. Shallow-rooting herbs like chives, cilantro, and thyme thrive in containers as shallow as 6-8 inches. Medium-rooting herbs, including basil, parsley, oregano, and mint, prefer a depth of 8-12 inches. For deeper-rooting varieties such as rosemary and lavender, aim for the deeper end of the range, around 12 inches or more, especially for perennial growth.
Beyond depth, ensure your planter has proper drainage holes to prevent waterlogged soil. Use a high-quality, well-draining potting mix and consider the planter's material; wood and fabric pots offer excellent breathability. Place your herb garden in a location that receives at least 6 hours of sunlight daily. With the right depth and care, your compact urban planters will yield a bountiful and aromatic harvest all season long.