I’m just back from a very interesting 10 days in Malta. Truth be told, it’s not someplace I’d ever intended to visit, but a dear college friend of mine was on sabbatical there this fall, and the invitation seemed too good to turn down. Turns out, it’s quite the place, Malta. A tiny rock of an island not far from the Libyan coast, this miniature nation state has an incredibly long and diverse history dating back over seven thousand years. The oldest architectural remains in Europe are found there (which I toured, spectacular!) and the island has been occupied, in succession, by the Phoenicians, Greeks, Romans, Byzantines, Normans, Spaniards, and Italians, each helping to produce a remarkable cultural heritage.
Perhaps even more remarkably, Maltese farmers manage to grow a fantastic variety of crops on what is essentially a tree-less block of barren limestone. Of course by November, most of the harvest was already in, but as I traveled about the island, I came upon field after field of the most spectacular leeks I’ve seen in a while, just finishing their long growing year:
This lush growth is all the more remarkable when you take a closer look at the soil:
Those aren’t clumps of dirt you’re looking at, they’re rocks: thousands and thousands of bits of limestone, surrounded by what is, in essence, stone powder. Imagine having to garden in soil like this! Yet the Maltese do, with spectacular results. What’s their secret? Well, it’s two-fold.The first part is adding sufficient organic matter: Maltese fields are lightly manured after each harvest, and this annual dose of organic matter not only feeds the crops, but also helps the soil retain much needed moisture during the dry summer months – something that simply adding fertilizer alone wouldn’t accomplish. The second key to success is knowing when enough organic matter is enough. Simply because a soil is rich doesn’t necessarily guarantee a good garden. In fact, soils can contain too much organic matter, something I learned to my dismay this summer in my own vegetable garden. Last fall, I covered the beds with a good foot or two of leaves as I had the past three seasons, which I dutifully tilled into the soil this past spring. But it seems I overdid it: I added so much composted matter that the drainage was adversely affected, producing a dark, muddy soil that pooled water. Without sufficient air at the roots, my plantings weren’t able to absorb food and moisture properly, and the result was the poor growth I experienced this summer. (Of course, record rains and a hurricane didn’t help either.) Fortunately, the situation is self correcting: by next spring the excess organics will have sufficiently broken down and proper drainage will be restored. (I may also add a bit of grit in the form of sand to help things along.) But in the meantime the lesson is clear: add organic matter regularly but sparingly to your garden, never changing the soil’s composition by more than 20% or so at a time. And above all, maintain good drainage. It’s the sine qua non of successful vegetable gardening, as the clever Maltese will attest.