After purchasing a terra cotta plant containers, you may want to make it look like it has been out in the garden for years. Aging terra cotta subdues the bright orange on the container, making it look more at place in your balcony garden. Most gardeners prefer the way an aged terra cotta container looks over an unaged one.
Each aged container will have a different look, with white spots and green mossy spots. You can always just plant your container as you normally would with any type of container plant, and the terra cotta will become aged over time. You could purchase used containers that are already aged. Or you can speed up the process and age it yourself.
To age a terra cotta plant container, all you need is some plain yogurt, a dry foam paintbrush and a terra cotta pot. Concrete and hypertufa containers can also be aged in this way, but remember that aging with yogurt works only with porous materials. This will not work for plastic plant containers (you can paint plastic containers to make them look aged). The final effect of the yogurt aging will be a green patina effect. Patina effect naturally appears on metals and woods with age. The most famous green patina formed on the Statue of Liberty, which is made of copper (which is reddish-brown), a metal that turns blue-green over time when exposed to air and water.
Soak a new, dry terra cotta container in water for 15 minutes. Get about a cup of plain yogurt, and brush on the yogurt with a foam brush. Uneven painting will create the most natural look. Brush more yogurt on other areas than others. For four to six weeks, keep the pot in a cool, moist place in your balcony garden. Do not keep it indoors, as it will smell and attract garden bugs for the first few days.
Your terra cotta plant container will become more aged with time. The use of plant fertilizers, as well as exposure to the elements, will create white spots and other aged looks. Just plant your container after four to six weeks and watch its colors and textures evolve over time.