Friday, May 07, 2010

Math: On second thought....

Well, all that math was correct, but perhaps the premises were wrong.
From that post: the average person in the US consumes about 322 lbs of vegetables & soft fruit annually, and 200 sq feet can yield over 300 lb of veg & soft fruit over a 4 to 6-month growing season at intermediate Grow Biointensive yields.


Here in the San Francisco Bay Area, we have year-round growing.  Winter vegetables produce much less yield per square foot than summer veg, so it's not exactly a doubling of the numbers.  Instead of 300 lb /4 - 6 months, let's call it 500 lb / 12 months.  And this math says:

1050 lbs/year for the three of us, minus fruit tree yield = about 900 lbs/year for the 3 of us.
So if 200 sq feet yields 500 lbs/year, then I'll need to aim for 400 sq feet for a thousand pounds a year, giving 100 lbs extra as herbs, pest damage and insurance. If the beds are laid out in 100 sq ft each, that means 4 beds.

Four beds.  Not six.  See, I was wondering about that.  Robert Kourik, in his EXCELLENT work Designing and Maintaining your Edible Landscape Naturally "It takes an exceptional person, or special circumstances, to make a success of a landscape that is bigger than 1.200 sq ft and almost 100% edible."  He says that a couple almost never uses more than 300 sq ft, and frequently scales back to 150.  Later he puts in bits about starting small, with 100 sq ft, and that a family of four might eventually like 600 sq feet.  Hm.  Sounds kinda contradictory, but the reasons are explained in context. 

So I guess my best plan is to prep for 6 beds, be prepared to stop at 4 or so if necessary, and just put potatoes wherever there is extra room.  And garlic.  And asparagus.  Ooo!  Blueberries!  Not sure what you'd make with blueberries, asparagus, garlic and potatoes, but there's gotta be something because those are my favorite veg (for today).


Fun Fact for this post: winter veggies have good defenses against freezing: they create sugars. So a good hard frost will make your winter veggies much sweeter.  This is why ugly artichokes with black bits and skin hangin' off are so much more tasty than their pretty but bland and bitter brethren.

2 comments:

Anonymous said...

So this is where all of the 'Fun Facts' moved to. Your blog is looking great Plot.

Yhor

plot_thickens said...

Thank you so much, Yhor. You're a total sweetie.