These Sundaville® hydro granules in combination with the potting soil are the best basis for your mandevillas. Hydro granules are perfect as a basis for your planters. This is due to the perfect properties of hydro grains. It ensures that too much water is absorbed and a shortage of water is released at the root. As a result, the plant is less likely to experience stress from too much or too little water. In addition, hydro grains also provide oxygen to the roots. Due to oxygen at the roots, nutrients are better absorbed and the plant will grow better. Our hydro granules are available in 10 liter bags, how much you need depends on the size of the pot. Use hydro granules for about 20% of the content of the pot.