Becoming a soil scientist

You all have probably heard bits and pieces of our struggles over the last few years with our soil health. It’s been a real journey and one that is still ongoing, but I have learned a lot and am finally at a place where I want to share some more of the details of what we are uncovering.

It starts with the geology of our land. Our farm is situated on a rich and deep bed of limestone. The soil is a heavy clay loam. Some areas are loamier and more pliable than others. Some fields are more clay dense and difficult to manage. All of our land is nutrient-rich and starts with a pretty high PH (largely because of the limestone). When we first started farming I didn’t do enough soil testing and I wasn’t very focused on the balance of the nutrients in the soil. I operated under the assumption that as long as the crops were producing well everything was fine. And it was fine…for a while.

Starting about 4 years ago however, I noticed that some of our crop yields were decreasing and some plants were showing strange signs of illness and stress, particularly our long-season summer crops (think tomatoes and peppers). The issues were especially pronounced in our tunnels. At first I blamed the issues on a myriad of probable environmental factors: weather, bugs, transplant problems, etc. But, I also started doing more thorough and more frequent soil tests. The tests showed that our nutrient levels were off the charts pretty much everywhere, and that our PH levels were very high (7.8-8). In some ways this didn’t seem so bad—plenty of nutrients is a good thing, right? But the high PH levels combined with results from tissue samples of sick crops indicated that the nutrients in the soil really weren’t available to the plants.

So we started doubling down on the things that we know can help lower PH and increase soil health: adding elemental sulphur, cover cropping, adding compost and other organic matter, doing more focused crop rotations, and resting the tunnels, among other things. But none of this seemed to be helping. Crops kept doing poorly, bug pressures were up, yields were down. I felt like no matter how hard I worked I was losing ground. It also felt like it was my fault. Like because of my farming naïveté I had neglected the soil and ruined the land (a bit dramatic, I know! I sound just like my 4 year old during a fit: “but then I’ll never, ever, ever get it!” :). Honestly though, the last few years of my farming career have been a little bleak. And yet… we had babies! And our community never ceased to support us. Demand for our food remains high regardless of my struggles, and we have built an amazing crew who wants to work here and who wants to keep farming here. So, even though there have been more than a few moments over the past couple of years when it seemed like I should throw in the towel on this whole farming thing because I’m clearly not that good at it, there are just too many reasons to keep trying (back up the hill Sisyphus! You can do it!).

Finally, last year I had a breakthrough. One night, skimming one of the many farming newsletters I’ve subscribed to over the years, I read an article describing how irrigation can have a huge impact on soil health. High PH and high alkalinity (confusing I know, but they are in fact two different measures) in water can both raise the PH in your soil and inhibit the movement of molecules (i.e. nutrients) through the soil by binding up those molecules, leaving the nutrients inaccessible to plants regardless of their abundance. Limestone, it turns out, commonly leads to very alkaline water.

I read that and was immediately suspicious that this had to be a big part of our problem. Which is just the biggest kick in the pants. Water, deep, cold, beautiful, plentiful water, has always seemed like my one true advantage as a farmer. How manny times have I said to myself: “It may be the muggy, buggy south, but at least we have water!”

It’s hot here; we irrigate a LOT, especially in our greenhouses, our most intensive growing areas. Furthermore, it doesn’t rain in the tunnels (again, a virtue in most respects!), so nothing ever washes out all of the minerals and salts left behind by alkaline water or balance out the artesian water’s high PH with the rain’s comparative acidity.

What to do? We’ve been toiling diligently year in and year out, trying our absolute hardest to be good stewards of the land, only to find that our most valuable resource (water) is taking us two steps back every time we move one step forward.

Enter soil science. Thanks to a lot of research and a lot of conversation with other great farmers in the area (huge shout out to Glade Road Growing and our Certified Naturally Grown network!), I think we might finally be on a path to mitigating our PH issues. We have learned that you can inject an acid solution into the water that will lower the PH and bring the alkalinity down such that our limey, mineral-rich well water (PH of 8, alkalinity of 305 ppm) ultimately mirrors that of rain water (PH of 5.5, alkalinity around 75ppm).

This season we are trying out the water acidification in our tunnels where the issue is most pronounced, where we do the most intense growing, and where we have the most control. We have set up a Dosatron system (basically a series of metered pumps connected to our well water) that allows us to add organic nutrients to the soil while acidifying the water at the same time. The acid solution we are adding to the water has a gradual, cumulative effect of improving the soil quality over time, but also immediately and temporarily improves plants’ ability to take up nutrients by mitigating the alkalinity of the soil.

It has taken a lot of experimenting (and more reading and studying than I have time for!), but so far it seems to be working! I don’t want to jinx anything, because the season is still young and our long season summer crops are just in their first flush of growth, but as of today the tunnel crops look better than they have in years.

And I can’t even tell you what a balm it is to my soul (and my ego!) to see the healthy, verdant growth of the young cherry tomatoes, cucumbers, and pepper plants… maybe it’s not me after all!. There is literally nothing more painful to a farmer than watching plants you’ve worked so hard to nurture suffer and die under your care. I am so, so, so hopeful that we will have a bountiful crop this year and that maybe, just maybe, I can feel like I’m good at my job again. Fingers crossed y’all! I’ll keep you posted :).