Protecting the Soil
The sun yesterday was the first of the season that I would describe as oppressive. I mean it really beat down on me hard to such a degree that I could feel the water being sucked from my pores. Usually I could count on one or two passers-by stopping to say hello or to ask a gardening question or two, but not that day. Nobody wanted to be out.
I knew going in that I was going to be cooked by the sun as I watered the plants, so to prepare I covered every bit of exposed skin with sun screen, I wore my trusty Patriots cap over my head, my *buff around my neck, and my sunglasses without which my retinae would have been seared into uselessness. I also brought a 38 oz. container filled with what was once cold water, which I downed as I stood under a nearby tree during my breaks. Life is really going to look different once the humidity comes over us. For now, I'll enjoy the relatively low dew point.
For the plants it was what I assume to be the molecular level a photosynthesis frenzy, especially for the sun-loving tomatoes. Their greens looked greener than usual, and their leaves felt cooler than I would have thought. Aside from some bothersome insects taking nibbles here and there, the plants looked happy and surprisingly hydrated. Never-the-less, I still took it upon myself to check the soil moisture as my OCD nature compelled me to.
When I put my finger into one of the lettuce beds, I expected it to feel a little dusty or sandy as if there were little water, but instead it was cool and moist. Not trusting my own nerve endings I plunged my meter in to see for sure. Amazingly it confirmed what my finger felt, which was that the soil was not only moist but downright drenched!
In the BGG I'm always surprised to find that despite not having been watered in several days the soil often remains moist for at least 6 inches down. Being more of a direct-in-the-ground kinda guy when it comes to planting food-bearing plants, I'm not used to the plant boxes as they are in the BGG, and even though I know better, I sometimes feel as if the raised boxes themselves should contribute to further run-off. That's not only wrong, but more often than not it's the exact opposite and that it is raised boxes that are often better at retaining water.
Now we've been pretty good about watering the garden consistently, but that alone doesn't account for the wetness of our beds. Even on hot days they seem to retain a lot of what we put in. We can credit Farmer Dave and the seasons he spent building the soil for its healthy state. Due largely to his efforts, the BBG soil is a fertile organic sponge that would give even the dirt in the Garden of Eden a run for its biblical money. Even so, there's another thing working for us to help keep the water in the ground that's the thick layer of straw we have over the beds.
A Wound on the Earth
The first time I saw straw used as ground cover was on people's lawns where they would put down seed on open dirt and then lay straw over the seed. The purpose of the straw is to protect the seeds below with a biodegradable substance that also keeps moisture from evaporating right out of the dirt. Initially I dismissed the straw as another gardening fad that would drift away in the wind quite literally and figuratively. But then as I gardened, learned more, and stopped being a negative Nellie, I found that straw is a very much a gardener's best friend and for me the perfect ground cover.
Most people don't realize that soil works best when it is covered and not exposed directly to the sun, wind, and rain. Doug, one of our Westchester area garden friends who both Farmer Dave and I see as an agricultural guru, once said to me that exposed ground is like an open wound on the Earth that needs to be healed with ground cover. For some it may sound a bit new agey the way he puts it, but when you think about what Doug is saying, he's positively spot on.
Before European settlers came over to North America and started tearing down forests and plowing fields up here in the green Northeast, the forest and land had a natural ground cover in the form of dead leaves and dead vegetation. This layer of cover protected the soil and the organisms in it and allowed the soil ecosystem with all its crawly bugs, opportunistic fungi, and workhorse bacteria to thrive. When people started cutting down the forests and farming the land, they found a rich fertile soil that was great for growing all sorts of crops. However over time, the loss of that ground cover changed the soil environment and caused it to lose much of its nutrient content and in many places altered the entire ecosystem. Now I'm not talking dust bowl stuff here, but more of a change in the local environment that wasn't exactly good in the long-term.
Fast-forward to today when we plant our gardens, most of us would turn over the ground, loosen up the topsoil, plant the seeds or starter plants, and then water religiously not giving a thought to ground cover. Sure we still got our crops to come up, but we probably used about 30% more water than we had to. Then there are the weeds — those darn weeds. Without ground cover these invasive little pests more easily find purchase in the rich dark uncovered soils, taking away precious nutrients and water meant for our plants. Ground cover would have kept that from happening, and straw would've been the best stuff for us to use.
Straw — The Gardener's Best Friend
Straw is cheap, versatile, and it really helps keep the water in the ground. What's also great about straw is that it doesn't really hold moisture itself but instead lets the water penetrate the ground eventually reaching your plants' parched roots while preventing that same water from up and evaporating away. It remains light and doesn't hinder the growth of seedlings from sprouting up, yet it also makes it easier to spot and remove weeds before they can root in too deep.
Other types of natural ground cover include hay, wood chips, or shaved wood. These are all fine and dandy for keeping your flower garden looking good, but they don't really do well with vegetable plants. Wood chips would simply hinder seedlings because of their weight and size. In addition it would hold too much of the water coming from overhead and not let it reach the plants below. Hay is similar in this respect except it is more likely to rot and introduce disease to your vegetable plants.
The only real knock against straw is that it can sometimes blow away in high winds. But really, if the winds are strong enough to blow your straw away, then you may find that your garden likely has bigger issues worth addressing as a result.
Another potential issue is for those looking to reduce their carbon footprint, straw is usually brought over long distances in trucks. Even I wrestle with this one a bit. However, one can make a strong argument in saying that the water saved by using straw almost completely offsets the environmental cost of its transportation.
There's Straw and then There's Straw
There are several different types of straw out there, and you have to be careful with what you use. The only two I've ever used are pine straw and wheat straw (although it's possible I've used others but didn't know it). Pine straw tends to be a wee bit acidic so you have to keep track of your soil as it breaks down as it may affect certain vegetables from season to season. I prefer wheat straw if for no other reason than I don't really have to think about it after I lay it down. It's light, cheap, and does its job well. Of course I'm willing to concede that there may be some other sort of magic straw out there I've not used, overall, I'm a fan of the wheaty stuff.
Next-Level Ground Cover
If you're looking to go all conservation/organic/child-of-the-Earth/save-the-planet to the max, the absolute best ground cover is crushed leaves. If you have a maple tree nearby, all that stuff you usually rake up and send away year after year could easily be put into a couple of covered trash barrels and used in the spring for your garden ground cover.
If you want to go to the next level even with the leaves, as you lay them down on the beds crush them up with your hands so that they crumple and break up into small pieces. It may not look pretty, it may be a ton of work, and it may feel a bit dirty crushing dry, old, leaves in your palms, but wow does it ever make for great cover. Personally, I would love to do that if I had time, but for now I'll stick to the straw.
As the BGG meanders into the summer and the days get hotter, we can be content in the fact that our ground will be well protected by its blanket of straw. As for me and the rest of the gardening crew, we'll just have to settle for the sunscreen.
*For those unfamiliar with the garment known as a buff, it is a tube of fabric that you can use like a scarf, a headband, a bandana, or even in these times as a face covering. A great thing to do on hot days is to get it wet and wear it around your neck.