Container gardens are a great way to create a garden when you don't have a yard. They are easy to use, versatile and come in a wide variety of shapes and sizes
Foliage is an extremely important and often underrated component of any design, whether in a container or in the garden. Long after flowers are gone, foliage continues to provide wonderful contrasts and textures.
Fine textures are feathery and delicate; they enhance foliage and colors in neighboring plants.
Bold textures create an impact. They add stability to a design and create focal points.
Container designers often organize plants into three categories: accent plants, fillers, and trailing plants. Although all three categories are frequently used when designing a container, this is not a rule.
Designing with color is fun. Everyone should be encouraged to experiment with it. Some colors are hot (reds, orange and yellow), while others are cool (blues, purple and pinks). White often brings out the intensity in another color, looking very classy when paired with green and pastel and pretty when paired with pale yellow. Beautiful arrangements can be made by combining varying shades or hues of the same color.
Repetition is as important for container design as it is for garden design. When there is too much variety, the eye does not have a resting point. Repetition creates continuity in an arrangement and ties the composition together. Repetition does not necessarily mean using the same plant repeatedly in one container; plants can be repeated throughout a grouping of containers. Using plants with the same color or shape can be a form of repetition. Conversely, using the same plant in different colors effectively creates a sense of continuity.
Understanding scale and proportion is important when planting a container. Containers are most effective when plants of contrasting heights are layered in tiers from tall to small. Large accent plants, such as cannas, can dwarf the other plants in a container unless there are transitional, medium-height plants to draw the eye to the under-planting. Layering also covers up the bare undergrowth of taller plants. Try to envision what the plants will look like when they are fully grown. All containers will need some pruning or formative training, but it is important to get the scale right from the start. Tall plants look best in pots with wide bases (they look out of balance in containers with narrow bases), and small, rounded containers look their best when planted with mounding plants that mimic the shape of the container.
Rather than trying to fit all of your good ideas into one large pot, group a number of containers together to create a tableau or miniature landscape. Plants with contrasting shapes or textures can be placed side by side very effectively. Many plants thrive when planted separately, rather than competing for space in a crowded container. Grasses, for instance, look wonderful when given center stage in a pot all by themselves.