I ended up buying some shell peas at the Farmer's Market on Saturday, since they were there. I then came home, and picked my snow peas. Today, I cleaned both batches, and looked at the results:
"Waste" from the home-grown snow peas vs. yield of the shell peas
"Waste" from the shell peas, vs. yield of the snow peas
It also took me almost twice as long to shuck the shell peas than it took to cut the tops off the snow peas. Now, I'm not the fastest shucker east of the Pecos, but still...
I decided to weigh everything, just out of curiosity. Shell peas - 24 grams peas, 390 g waste! Snow peas - 208 g peas, 22 grams waste!!
I can't stand seeing that much waste with the shell peas, even though it can be used to make stock, then get chucked in the compost. Snow peas just seem more... efficient to me, in terms of work and yield.
Of course, yield isn't the only thing to think about. What about nutrients, especially protein? From the USDA Nutrient database (a very handy site, btw):
Per 100 g:
Snow peas: 2.80 g protein, 42 calories = 6.7 g protein per 100 calories
Shell peas: 5.42 g protein, 81 calories = 6.7 g protein per 100 calories
Per gram, shell peas have more protein, but also have more calories. Per calorie, both types of peas have the same amount of protein.
So why grow both? They have very different uses, and as much as I love snow peas (especially raw, straight off the plant), I prefer to use shell peas in soups.
And besides - Dad would disown me if I didn't grow shell peas for him to eat. Raw, straight off the plant. I come by my weirdness naturally :)
*yeah, yeah, I know. Old joke. Gimme a break - I just spent the last four days working like a mad woman. I need a weekend to recover from my weekend!