I started making my own laundry soap a few years ago. I just love that it is not only inexpensive to make, and it cleans great!
After awhile of using the recommended amount of 1/2 to 1 cup per load, I thought: if one cup is good....1 1/2 cups would be better! or even 2 cups! Sometimes I would just guess and pour some in!
Ya.....well....there is a reason why there is a recommended amount.
as I found out first hand, more is not necessarily better.
In an article I read recently, Marilyn from parade.com, explained why. Although it is talking about laundry detergents you buy in stores I believe it also applies for homemade laundry soaps as well, seeing I experienced what she explains:
Ask Marilyn: The Right Amount of Laundry Detergent
parade.com Nov 25th 2012
Marilyn: My wife doubles or triples the recommended laundry detergent amounts to get more suds. How can I rationally argue that she should use the indicated amount per load?
Ask her this question: Why would any manufacturer direct consumers to use less than the optimal amount? Their laundry might not get clean, and the company would sell less product. That doesn’t make sense!
Consider a bubble bath. Do you get any cleaner? No. And your dishes get clean in the dishwasher with few suds, don’t they? Yes. But Americans love suds so much that manufacturers use high-foaming formulas whenever they can. Shampoo is a good example. The froth does nothing but make a mess in the sink that takes time and effort to wash down the drain. These cleansing agents all work differently, of course, but they do have something in common: The suds they produce do not reflect their cleaning action.
In fact, using too much detergent can make laundry a bit dingy and stiff. Also, the suds can cause problems with the machine long-term. Some washing machines even have software designed to overcome our tendency to use too much detergent. They sense the excess suds and add extra rinses!
Now homemade laundry soap does not suds like store bought laundry soap, which makes it very good for low suds-sing washers. But if you use more than the recommended amount you will have the same problem, over a long period of time, with your clothes becoming dingy and stiff.
I actually had to go to store and buy laundry detergent just to get my clothes clean and whiter again. I am slowly going back to my homemade laundry soap again, but this time I am using the recommended amount and no more!
Here is a link to homemade liquid and powdered recipes.