I wrote this because Wayne had asked me about it, but I thought the post may be more appropriate here. I'd love to hear others' experience with growing green shoots and wheatgrass and what works for you!
After experimenting with a few methods I found that keeping it simple is best for me. I use shallow 9" x 9" plastic tubs w/ transparent colored lids and plastic embroidery sheets cut to fit the inside of the tubs for the roots to grab hold of. I tried using clay tiles under the sheets to hold moisture but it resulted in too much standing water and a fruit fly problem. I was initially concerned about using plastic but after researching found that most of the toxic transfer to food happens when plastic is heated, like in the microwave. Also the plastic is much easier to keep clean and sterilize with food grade hydrogen peroxide.
I soak the seeds overnight.* The next day I rinse them a few times then spread evenly on top of the emb sheets in the tubs and cover with the lids slightly askew for a bit of air circulation. After a few days of growth both the wheat and sunflower seeds' roots have grabbed the little holes in the sheets so I can run it under a pretty heavy spray in the sink and they stay put. I do this once in the evening using more care with the "new" seeds. This keeps the mold and fly problem to a minimum. Once a day I also generously spritz with filtered water with a bit of hydrogen peroxide and Earth Juice Catalyst [1t per spray bottle]. I remove the lids after 4 days.
I built a 24" wide and 6 feet high stand with 9 shelves and a grow light on a 12 hour timer hanging from the top shelf. One could use an open bookcase because the tubs aren't very deep. I yield enough sunflower greens for a small salad a day, to which I add I add one pound of alfalfa/ clover/ radish sprouts. I get about 1.5 ounces of wheatgrass per day. I yield 2 ounces when I soak them in hydrogen/ water for ten minutes [then rinse] before soaking overnight, but I'm saving up for a gallon of the stuff because this isn't economically practical at $5/ pint.
This isn't a sophisticated system. I have a tiny kitchen in my efficiency and I needed to come up with a method that fit into the space and wasn't too much trouble to manage daily. It was also economically feasible, as the automated systems aren't practical for wheatgrass and are ridiculously expensive. The plastic tubs were $1/ ea at the Dollar Store, embroidery squares at Walmart were $3 for a 12 pack. I purchased the Earth Juice Catalyst online for about $12 and at this rate it should last me at least 3 years.
* Non-sprouting sunflower seeds are the ones that mold. The good seeds separate from the bad when soaking; keep the floaters and throw away the sinkers before "planting." I use 1/4c of wheat and 1/3c sunflower per tub since many of them are no good.
Edited to correct the dimensions of the stand and my english.