As a gardener I am sure you have experienced first hand the accumulation of salts on when using clay pots. Clay pots or a staple in the garden industry and to the home gardener. They are inexpensive and easy to use. In my family we have terracotta pots that have been passed down from our grandparents. And yes, we still use them – why not?
An advantage over plastic or resin pots is the porous clay pot will tell you when the potting medium needs to be leached. When water evaporates it will leave behind the minerals and fertilizer salts. Over time this will build up and can have adverse affects on the plant. As these minerals build up they can draw out moisture from the roots. Some symptoms of mineral/salt build up in the potting mix are brown tips on the leaves, white crust on soils surface, white crust on the pot, slowed growth, and pest problems.
The best thing to do to help prevent and solve this problem is to stick the plant in the sink and allow water to run through the potting medium. As the water drains away watch for it to change from light tan color to clear. Once the color changes allow the water to run for about a minute longer.
While you are doing this clean the saucers too. Minerals and salts will also build up in the saucers. Scrub them out with a brush and let them air dry.
If plants are too large for the sink put them in the shower. They will appreciate getting the dust washed off too.