My friend Dean Gooddale has made me a believer in the importance of soil testing to organic gardening, and particularly to greenhouse gardening. You can't have healthy plants without healthy soil, and you can't necessarily tell what your soil needs without testing it.
So a few weeks back, I submitted two soil tests to our local extension agency: one from the back yard, where we have lots of bare clay from the construction work that was done last fall; and one from the front yard, where we've had a sheet mulch cooking since October. I consider both of these to be "before" snapshots, but the back yard is definitely more "before" than the front!
The two-page report (at left and right - click an image to see a larger version) tells us that the backyard clay is slightly alkaline (7.2 pH) and the frontyard soil under the sheet mulch is slightly acidic (6.8 pH). I take this as good news, because the compost we've been producing all winter contains a lot of citrus peels and is liable to be acidic. If the soil were already acidic, I'd have nowhere to put the compost! As it is, many of the plants I'm hoping to grow this year require acid soil (berries and nightshades), so the compost will be perfect.
Both samples tested low not only for nitrogen and organic matter but also for phosphorus and potassium. This is bad news, because I don't know whether the compost and mulch we've got will supply those nutrients. The report recommends I add chemical fertilizer and till it in 6 inches deep -- two practices I have been hoping to avoid in favor of Ruth Stout's "no-work" method. But if I don't add fertilizer, we risk having a very disappointing crop this year... and wasting a lot of work!
I'd be interested to hear suggestions from those of you who have been there... should I stick to my principles and hope the mulch lives up to its promise, or swallow my pride and til in a chemical fertilizer this one time?