I also found that certain (ie Seventh Generation) eco-friendly detergents didn't work so well. So I tried a bunch more and found that the conventional Palmolive's "Eco" detergent (gel) works quite well. I have no idea whether its as eco-friendly as the non-conventional brands, but it does seem to work better. I also pre-scrub the really dirty ones with a small bowl of soapy water and a sponge. Good luck!

We don't usually have enough dishes to run the dishwasher every day.  Some things will not come off if you let them sit in there and dry out so I keep a dishpan in the sink and put those sticky dishes in there with water to cover until I'm ready to wash them or you can just give them a quick rub after they have soaked a while.

I have been able to avoid the same issues myself by washing the messiest of the dishes immediately after use, before they dry into food-mortar. I live in Colorado, which is extremely arid and mortar-producing, so it can take a bit of planning to figure out the best time to run the dishwasher and/or hand wash everything, which isn't always realistic. But it helps.

On the flipside, running appliances at night instead of during the day can reduce local energy loads during peak hours, which complicates the dish issue immeasurably. Save the climate or save the watershed? You chose...

Not all eco-friendly cleaning products are created equal.  I've been quite happy with the Ecover tablets and the price is reasonable.

If you don't fill up the dishwasher with one meal, using the rinse-only cycle in the interim helps a lot.  Longer-term, when shopping for a new dishwasher, use publications like Consumer Reports to get a good one.  They really do vary a lot in their ease of use and cleaning ability.

Why shouldn't all the rules that apply to camping in the wilderness apply to living out of the wilderness? Take only fotos and leave only footprints. I hand wash my dishes. I use solar hot water from the hose in the summer and hot water from my woodburning stove in the winter. If all the dishes are from your family where are the germs on the dishes that you all don't expose yourselves to on a daily basis anyway? We use the same dishes in the evening that we use during the day. We have our own "mess kits". I use a cast iron skillet and wipe it clean without water. Hot water removes grease and if the water isn't hot enough a little detergent does help. A towel dries without leaving spots.
I think we're all a little too paranoid about our owngerms and a little bacteria. The worst thing is you might get sick or even die. A few humans dieing wouldn't really hurt the species; we're way over budget.

Dear Umbra,
   I tried turning down the temp of my hot water heater to save energy and using the eco friendly dishwashing detergent and got the predicted results: half my dishes were still dirty, and worse, the food had hardened onto them.  It got so bad that I called a dishwasher mechanic to fix my dishwasher.  He taught me about dishwashers.  You need 3 things for the washer to clean your dishes.  First, the mechanical part of the dishwasher must function properly; ie, the spray pressure must be sufficient.  Second, you need heat.  My water was too cold.  Third, you need chemicals.  If you don't have all 3, your dishes will not come clean.  So what I do now is what all your other commenters are doing.  I soak everything in water in the sink until I fill the dishwasher (about once every 3 days).  Upon reaching critical mass of dirty dishes, I go downstairs and turn up the hot water heater to VERY hot, wait an hour for it to heat up.  I load the dishwasher, clean the sink with the hot water so as to get the hot water up to the kitchen, load the dishwasher with Cascade, and then run the dishwasher.  About halfway through the cycle, I turn the hot water heater back down to a very low setting where it stays until I need to run the dishwasher again (another 3 days).  Now all my dishes are clean first time through.  Many people think I'm off my rocker to adjust the hot water heater just to run the dishes, but it really only takes less than one minute to do this.
Greg

Alas, I did the research and bought an energy-star dishwasher.  My water usage immediately went up 24% and stayed there compared to pre-dishwasher days, and my dishes aren't as clean. Maybe my hand-washing technique was ultra conservative with water, but I'M NOT GOING BACK!!!

If anyone has done research on how using styrafoam disposable trays compares to durable tray wash water consumption impacts, I'm all ears.

The only way I can see mechanical dishwashers being more efficient is if you compare it to idiots running hot water full blast with a toothbrush over an open drain. Is that really the way most people wash up? We use half a dishpan of hot water to wash and maybe  another litre of cold dribbles to rinse.

Polystyrene is evil and should be avoided at all cost! I can't Google the details at the moment (Im at work) but using anything that is disposable and won't biodegrade for centuries is just evil. Also, I've read info that it can cause very bad things if ingested. There are many cities around the world that have already banned or working on banning polystyrene much to the chagrin of restaurant owners.

Remember the 3 R's: Reduce, Reuse, Recycle

The impact of toxics is probably fairly universal, as far as the detergent goes.  But the impacts of energy and water use depend on your personal sources of energy and water.  How environmentally friendly or unfriendly are they coming into your house?

I haul water from my own shallow well and heat it on a woodstove to handwash dishes, so I'm not terribly concerned about either the water or the energy.  I imagine someone in a dry area might be most concerned about water use, and want to turn their heater up accordingly, to avoid having to wash dishes twice.  Someone in a very wet area might be better off using colder water and more of it.  

On tip for those of us with hard water: replace half your detergent with borax.  It makes the detergent work better.

I agree with Greg about water pressure.  My well water is not only hard but filled with iron/sediment; it's been destroying my appliances.  I finally installed a whole-house sediment filter (super cheap, I used one from Sears).  I think it's too late for this particular dishwasher, but it has made an amazing difference elsewhere.

For anyone buying a new (or used) dishwasher.  Get one that heats the water to the proper temp.  Then you can keep your water heater low to medium all the time and have the equivilent of a tankless for the dishwasher.

Consumer Reports' finding was that enzymes in the detergent are what changed a medicore product into a good one.  You can find plenty of natural brands with enzymes.  If you must have phosphates, why not a pinch of TSP now and then?  At least it doesn't have the petroleum-based ingredients, synthetic fragrance, and other toxins.