The pebbles used for hydroculture are also ideal as a drainage layer in the bottom of your pots, so always start with a layer of hydro pebbles when potting a plant. A layer of 3-6 cm is sufficient, depending on the size of the pot. Hydro pebbles improve the water balance in the pot, so that your plant will grow better. It is important that outdoor pots have a hole in the bottom to allow excess water to escape.
You can also use hydro pebbles as a decorative layer on your indoor and outdoor pot plants. This layer will also help prevent the potting compost from drying out. Another alternative for a decorative or protective layer is bark or coconut mulch. The choice is yours!