Though you may be inclined to choose pots solely for their looks, each material has its pros and cons.

1. Terra-cotta ages beautifully, but it's porous, it breaks easily, and it cracks in freezing temperatures.

2. Cast-iron is decorative and tends to be formal. It's best in a shady setting, as it heats up quickly in direct sun.

3 and 4. Glazed ceramic pots bring color to the garden. The glaze helps them retain more moisture than terra-cotta does.

5. Lightweight and durable, fiberglass can look convincingly like stone or terra-cotta. The more realistic these pots look, the more expensive they are.

6. Cast stone (also known as concrete) is long-lasting and often treated to look antique. It is also extremely heavy.

Containers are a onetime investment. But if you're sticking to a budget, machine-made terra-cotta and plastic pots, which start at a couple of dollars, are the most economical choices. Ceramic, metal, cast-stone, handmade terra-cotta, and fiberglass ones can range from $15 to several hundred dollars.