If you like wheatgrass, you may be tempted to try growing it yourself. Growing your own wheatgrass is relatively easy, and decidedly less expensive than buying it commercially. Techniques and strategies for growing your own wheatgrass are described in detail in a few other articles. For the moment, we'll concentrate just on planting guidelines for juice yield...
Remember, these guidelines depend on a few basic assumptions. Hydration for your wheatgrass is critical. Before I moved to hydroponic growing, I often found that my wheatgrass would get dehydrated. Wheatgrass uses a lot more water than you would expect, and keeping it adequately hydrated (especially when growing outdoors) can be tricky. If your wheatgrass is dehydrated, you will get radically less juice.
Secondarily, make sure to account for the "waste" inherent to your juicer. Every juicer has juice "left" on the parts of the juicer once you run out of wheatgrass. Remember, dilute juice is much better than none at all. Although this part is personal opinion, I recommend running apple slices through your juicer after the wheatgrass. The apple will "push" the remaining wheatgrass though the system, into your cup.
From our experiences, here are the best recommendations that we can make:
I figured out yield calculations using "cubic inches" of wheatgrass. The cubic inches are figured by multiplying:
Lenth x Width x Height
In our sample, our length was 17, our width was 3, and our height was 8. This gives 408³" (cubic inches) of wheatgrass.
408³" = 3 ounces of juice
408³" / 3 = 136³" per ounce
Since it takes approximately 136 cubic inches of wheatgrass to yield an ounce of juice, you can easily work out the growing area. If you grow your wheatgrass to 8" (like me), you will need 17 square inches per ounce (just a little over a 4" x 4" square). If you only want to grow your wheatgrass to 6", you would need a larger area (closer to a 5" x 5" square).
If you were working with a 10" x 20" gardening flat, you would yield approximately 11.75 ounces of juice. By the same math, a filled MegaGarden should yield a whopping 27 ounces of juice, if I were to juice everything at once.
To be safe and easy, it's probably best to grow it in 5" x 5" batches, for single-serve quantities.
Speaking of growing single-serve quantities, make sure to read our suggestions about growing baskets in the article Hydroponic Wheatgrass for Beginners.