Last fall, as we headed into the fallow season, we decided it would be a good time to get a garden check-up. A garden is a living thing, after all, which means the same way you take yourself to the doctor for a physical exam, your garden needs a regular check-up too.
So in early December, garden co-manager Daphne Shuttleworth took soil samples from each of our beds and sent them off to Fedco Seeds, which provides a comprehensive soil testing service in conjunction with the University of Maine.
The first and most important thing soil testing looks at is the pH level. A healthy garden should have a pH level between 6 and 7, running slightly acidic to neutral. It turns out that the pH level in our food pantry garden had creeped up above the optimal range and had become slightly alkaline, with an average pH of 7.3.
There could be several factors that caused this, but we think the primary culprit may be compost, which tends to be basic or alkaline. This seems a little counterintuitive since we ordinarily think of compost as nothing but good for the garden, and usually it is, when applied in moderate amounts. But last year we laid down a lot of extra compost – about 700 pounds of it to be exact, spread across our 24 garden beds, which may have help short term by improving last year’s yield, while at the same time throwing our soil pH levels out of whack.
Fedco’s analysis provides not only a diagnosis but a suggested cure, which in our case involves a recommended application of 10 pounds of sulfur, spread evenly across all our beds, to reduce the pH level into the optimal range. We will start doing this as soon as the weather warms a bit more, by carefully raking the powdered sulfur to mix it in with the top layer of soil.
The report from Fedco covers a dozen other major and minor soil nutrients, all of which can have a dramatic effect on your garden health. It turns out that we are low on nitrogen, too high on phosphorus, and low on copper, iron, and manganese as well. So we have our work cut out for us over the coming months, making amendments to the soil, using feather meal or blood meal to increase the nitrogen levels, using Azomite to help with the copper, manganese, and iron. We will probably test again this coming summer to make sure that we have regained a healthy balance in the soil. Spring is almost here, and it’s time to get back to work.
Join us for the annual Seed Sorting Party at the Hampton Bays Public Library on March 18th from 6 to 7:30 pm. Enjoy some good company and refreshments while we assemble the materials for this year’s seed library.