Terracotta containers come in many shapes and sizes from simple pots to square sided decorative planters, urns and troughs. Carefully prepare your containers for planting. A lack of adequate drainage is probably the greatest single cause of trouble among container grown plants. Water must escape freely from terracotta pottery for outdoor use. Rain can soon upset all your plants in soil that is waterlogged for long periods of time.
Plants can grow outdoors in containers without drainage holes only if they are sheltered from rain.
Otherwise containers must have holes at or near the base. Most manufacturers provide these. Take steps to prevent fine soil from being washed out of containers and silting up your drains. Use drip trays wherever stains from escaping water may cause problems. They catch the nutrient rich drainage water, thru reducing the growth of green algal film on paths, windowsills and walls.