Plastic pots, including the new heavy duty composite versions that look like clay, last a long time, but they do have their drawbacks. When sitting in full sun, they get very hot, often to the point that the side of the pot that gets the most sun will prevent roots from growing there. In addition, while it is good they don’t dry out as fast, they also tend to hold too much moisture. Therefore it is important to always check the soil moisture level before adding more water. If you are currently determining if a container plant needs more water by touching the surface of the soil, this is a mistake, especially for large containers. If the soil is wet just a few inches below and you add more water, you can easily suffocate the roots with oversaturation. A gadget called a moisture meter (about $5-$8 in home improvement stores) is a worthwhile investment. The gauge tells you if the soil is dry or wet to a depth of six to eight inches (the length of the probe), not just at surface level.
Avoid buying pottery from Mexico, as although it is inexpensive, it is not worth the low price since they will disintegrate quickly. This type of pottery is fired at a low temperature. Low fired clay absorbs moisture inside and out, crumbling into nothing after just a few freeze/thaw experiences. Coating the inside with waterproofing material does not make any difference, as the exterior will still absorb rain and expand with heating and cooling.
High-fired Italian clay, glazed pottery and concrete planters are good choices, but each have features to consider before purchasing.
Italian clay is high-fired, making it quite durable. It is also known as Terra Cotta. These pots dry out quicker, so will need more water during the hot summer. However they breathe well, allowing roots to get the oxygen they need.
Glazed pots are coated with melted glass, which requires high firing temperatures. This is a wonderful way to add color to your landscaping no matter what you plant in them. They are pricey, but worth it. They will last a very long time. The options are wide, and what works best depends on your intent. While the ones with patterns and decorations are lovely, solid colors draw attention to the plant, not the pot. However, they do not breathe because of the glaze, so be careful not to over-water.
Concrete planter options are best for large plants. They are very expensive and require special delivery and equipment to set up…so make sure you know exactly where you want them because moving them around is not easy! Phoenix Precast Concrete is the only company I’ve found with a variety of shapes, sizes and colors. They do breathe somewhat, but also be careful not to over-water.
Planting in containers gives you so many options. Depending on the type and size, they can serve as focal points and entry statements. They can also make gardening easier, allowing you to move them around for proper sun exposure, and reach without bending and stooping. Planting containers can be higher maintenance in the sense that you will need to water more often and occasionally change the potting soil, but for many the convenience and joy they bring exceeds the maintenance.