Plant based, Sensitive and ‘Eco’ detergents are weaker than their mainstream counterparts, containing less surfactants and weaker surfactants. For this reason, increasing the quantity of detergent to 1.5-2 times the amount recommended for a heavily soiled load.
For the same reason hot water (60 degrees C) for both the main and prewashes will produce best results. This opens the fibres of the fabric, enabling the detergent to work more effectively. See the Hot vs Cold Water page for more information.
For detergent quantities and recommended wash temperatures refer to the Detergent Index.
For more information on what is in detergents and the function of the raw materials see the Mainstream Detergents, Fragrance in Detergent, Enzymes, Optical Brighteners pages and The Wash Wise Detergent Ingredients Info Sheet.