If you are interested in container vegetable gardening, a great way to start is to just get planting pots.
When choosing planting pots for growing vegetables, there are many variables to take into account: price, material, durability, environmental impact, size, shape, and color. Most of these are personal choices, but material, durability and environmental impact are variables that have certain characteristics that may help you make a better choice for your gardening situation.
Just to murk things up…terracotta (unglazed) is a type of clay, and clay is a type of ceramic (glazed or unglazed).
All of the pots in this category are bottom heavy, the lightest being the terracotta, and they are all made from renewable resources.
Terracotta (Clay) planting pots are probably the most common pots to be found. They take their brownish-orange color from iron oxide, which is found naturally in clay. They are widely available, relatively inexpensive, and come in a variety of sizes. Some of the problems you might have with terracotta are heat retention (when it is very hot the roots might get burned), cracking when frozen, porosity (they draw water from the potting mix, the plants dry out more quickly and need more frequent watering) and mineral salt absorption (causing a crusty build-up).
Unglazed Ceramic Pots vary in size, shape, color and price. They are usually very heavy and often do not have drainage holes or have only one. They crack and chip very easily and have the same porosity as terracotta.
Glazed Ceramic Pots are different from the unglazed and terracotta only in their porosity. Because they are glazed they hold water.
Concrete Pots are very heavy, which makes them suitable for trees and bushes. They are porous and need sealing. They are also high in lime and may be toxic to some plants.
Stone Pots are ornamental, beautiful and varied. They are also expensive and heavy.
Plastic planting pots are inexpensive, lightweight, widely available, water retentive and good heat insulators (they heat up quickly, but also cool down quickly). They come in a wide variety of sizes, colors, and shapes. They are durable, but will fade and deteriorate over time in the sun.
HDPE Pots (High Density Polyethylene) are made from a new synthetic on the market that is more decorative, extremely lightweight, made from recycled materials, and is less expensive than resin and fiberglass pots.
Reconstructed Faux Stone Pots are environmentally friendly because they are made from recycled material. They are less expensive than real stone pots and a great deal lighter, but are almost indistinguishable from the real thing. They are good heat insulators and are very long lasting.
Resin and Fiberglass Pots are stiffer than traditional plastics, are also lightweight, decorative (the shape and look of ancient urns), hold water well and last for decades. The drawback is that they are quite expensive.
Both of these kinds of planting pots are often used as ‘cache pots’—decorative containers which hold a planted plastic or resin pot inside.
Wood pots are natural and beautiful, but over time they become waterlogged. This causes them to increase in weight, discolor, develop mold and will eventually rot. Insects are drawn to the wood, which will probably not effect the plant, but will help the pots to decay. They will last a lot longer if you put a planted pot inside the wood container.
Metal Pots are plentiful and varied; do not chip, crack or break; and are set apart from other pots by the beauty that aging can add to the surface color and texture. Common metals used in pots are copper (rich), steel and cast iron (industrial) and zinc (dramatic and contemporary). The pots are non porous and therefore need to have drainage holds or else become a cache pot. Many of the larger ones are very heavy.
The new kid on the block seems to be Grow Bags, which are made of woven, UV treated polypropylene. They are strong, inexpensive, lightweight, durable, UV resistant, compact, foldable, strong, and comes in a variety of shapes and colors. Many have handles and all have good drainage holes. These pots are great for renters with small patios and people who love to garden, but move a lot.
Below is a Youtube.com video that will get you started with planting in a pot.