Terracotta or ceramic: what is the real difference?

Terracotta and ceramic are both fired clay, but the difference lies in the glaze: terracotta stays unglazed and porous, while ceramic usually gets a glaze layer that makes the pot watertight and less breathable. For a pot that lives outside year round, that difference often decides which one you should pick.

What exactly is the difference between terracotta and ceramic?

Terracotta and ceramic both start as clay fired in a kiln. The difference comes afterwards. Terracotta stays unglazed: no coating, a natural, slightly rough surface in the familiar orange-brown colour. Ceramic usually goes through an extra step, where a glaze is applied and fused with the clay body in a second firing. That glaze adds colour, shine and a smooth finish, while also sealing the pores of the clay.

On a handmade mosaic pot from Masr Potten & Vazen, a third layer sits on top: hundreds to thousands of hand cut pieces of glass, called tesserae, laid and grouted by hand. That mosaic covers the outside, but the underlying material, terracotta or ceramic, still determines how the pot behaves with moisture and frost. You can read more about that craftsmanship in our article on how handmade pots from Egypt are made.

What does glaze mean for how you can use a pot?

Unglazed terracotta is porous: it breathes, and moisture in the wall evaporates more easily. Many plants benefit from that, since it helps prevent root rot. Plastic holds moisture instead, which can leave the root ball too wet for some plants. Glazed ceramic sits somewhere in between: the glaze makes the wall less breathable than raw terracotta, but the clay underneath is still a different material than plastic.

That moisture behaviour has a downside in frost. Water that soaks into a porous, unprotected wall can expand when it freezes and cause cracks. Not every terracotta pot is frost resistant, and the same goes for glazed ceramic: frost resistance depends on the density of the firing and the glaze, not on the material category alone.

Terracotta or ceramic: which one for outdoors?

For a pot that stays outside all year, a few rules of thumb apply to both materials:

• Choose a pot explicitly labelled as frost resistant, whether it is terracotta or ceramic.
• Make sure it has a drainage hole, so rainwater doesn't sit against the roots.
• Raise the pot on pot feet or a small platform, so water can drain away from underneath instead of pooling against the base.
• During hard frost spells, keep an eye on the forecast; the KNMI (the Dutch meteorological institute) publishes current frost data per region.

If you want the full picture on getting a mosaic pot through a Dutch winter, our article on how to winter a mosaic pot without damage covers it in detail.

Does the material still matter indoors?

Indoors, frost isn't a factor, but porosity still is. An unglazed terracotta pot without a liner can let moisture through onto a wooden sideboard or a floor, while glazed ceramic largely removes that risk. If you'd rather not use a saucer or coaster, glazed or mosaic pieces are the safer indoor choice. If you use a decorative pot with a separate plant liner inside, the outer pot's material matters less, since the plant's moisture never touches its wall directly.

How do you judge the quality of a handmade pot, regardless of material?

Beyond terracotta versus ceramic, the finish of a handmade piece is a second useful measure. At Masr Potten & Vazen, every piece is handmade and hand mosaicked, inspired by the Egyptian mosaic tradition: no two pieces are identical, and small colour variation or a slightly uneven grout line are a mark of craftsmanship, not a flaw. For businesses and individuals who want something unique, custom work is possible in colour, shape and size, including a company logo worked into the mosaic.

If you'd rather start from a colour combination that fits your facade or interior, our article on choosing mosaic colours is a good starting point. And if you want to check which size fits your space first, see our guide to choosing the right pot size.