The Call, Column 48 – Water-Wise Gardening

6 06 2016

(June 5, 2016)

The Urban Farmer

Water-Wise Gardening

 

Despite the heavy rain in the forecast for today, I’m guessing that you’ve also noticed the sudden onset of warm, dry weather over the past few weeks. Though our southern New England climate has pretty much always been characterized by alternating stretches of warm, dry weather and cool, wet weather, the extremeness of this effect is being intensified by climate change. In the spirit of being well-adapted to the changing climate, and more generally with the important goal of resource conservation that underlies urban farming, today’s column is about a few key gardening practices and system-level approaches that aim to make the best possible use of water, both that which falls from the sky and that which is delivered through the faucet.

The name of the game is water-wise gardening. That begins with applying the best water you can as time-efficiently as you can, and ends with making sure that water stays where you put it for as long as possible. There are two classifications of methods and systems that we will discuss: gardening techniques that require little additional time or money, and more elaborate systems, that need some additional planning, but have a more pronounced benefit.

Let’s start with the so-called “low-hanging fruit”, simple gardening practices that have a pretty significant baseline effect with little overhead time or money:

 

  • Mulching. This is the single easiest and most effective water-wise gardening technique. By covering the soil around your plants with an inch or two of any fine organic material – grass clippings, shredded leaves, wood mulch, shredded newspaper, straw/hay, or even partially-broken-down compost, you can drastically slow down the rate at which the water evaporates. On a hot day, any un-mulched soil in my garden dries out within maybe 12 hours of watering or rainfall; mulched soil stays wet for at least a few days under the same conditions. Mulch also breaks down slowly into compost, which brings us to the next method.
  • Building organic matter content. Incorporating finished compost, manure, leaf mould, decomposed mulch, and other organic matter into your soil also drastically increases its water storage capacity with little effort. Organic matter contains a high level of what’s called “humus”, a not-well-understood organic chemical cocktail that is essentially the glue that holds our planet’s biosphere together. Among its many features, a high humus content is what gives soil its ability to store many times its own weight in water, thereby providing the plants’ roots with much longer-term access to water without more frequent watering.
  • Watering methods. Some measure of your water usage efficiency is the result of how and when you water the soil. By watering later in the evening or early in the morning, when the sun is not strong and the temperature is at the day’s lowest, the water will be able to percolate into the soil before being evaporated.
    In addition, much of the water that leaves the nozzle of the hose doesn’t make it to the soil, because it evaporates in mid-air. Following the above schedule helps to alleviate this, as does watering with the hose output as close as possible to the surface of the soil (that is, choosing those garden shower wands over sprinklers).
  • Layout of plants. There is a school of agricultural thought called permaculture, which theorizes that our agriculture performs best when it mimics the behaviors of natural ecosystems. Taking cues from this, you can maximize the soil’s moisture retention by being deliberate with the layout of plants in your urban farm. Specifically, by planting your main crops closer together than generally recommended, they will shield the ground from sunlight and slow water evaporation; a similar effect is produced by planting a “groundcover” of low-growing plants (i.e. strawberries, leafy greens, some smaller leafy root vegetables) amongst taller plants (like tomatoes), and has the added benefit of producing an additional crop from otherwise unused space. (Permaculture is a nuanced and very interesting set of theories, which warrants a few columns of its own sometime in the near future.)

 

Next, let’s talk about some not-very-costly systems that require a bit more planning, but have a more pronounced effect on your water usage:

 

  • Rain barrels. These are a great, self-sufficient way to meet your urban farm’s water needs, providing non-chlorinated, non-fluoridated water to your plants and animals while conserving our rapidly dwindling freshwater supply. Essentially, a rain barrel is any container (the bigger the better!) that is placed beneath a gutter downspout in order to catch and store rainwater. This water can then be used to irrigate your garden (especially with a drip irrigation system – more on this below). I would urge you to look at the much more in-depth column about building an urban rainwater catchment system that I wrote last June (you can find it here: http://tinyurl.com/zz9vh5y).
  • Drip irrigation. This is another planning-intensive but relatively inexpensive system to maximize your water usage efficiency. I am just beginning to install my own drip irrigation system in my garden, so I’ll tell you what I know so far. It is essentially a network of ½” and ¼” tubes, laid along the soil (hopefully on top of a nice layer of mulch). Water runs through the tubes and drips out of either small holes pre-drilled every few inches, or through specialized, fixed-flow-rate drippers that you install where you want. This network is initially connected back up to either a rain barrel or the spigot, first being filtered (to remove particles), pressure regulated (so that flow rates are predictable), and backflow regulated (which prevents a water cutoff from sucking the water back up into the spigot) by special attachments. For my large garden, I expect to spend $100 to $150 when all is said and done, and this system will save me 4 or 5 hours per week for years to come.
    This type of irrigation is beneficial because it delivers water directly to 1) the soil, preventing a lot of evaporation, and 2) the desired plants, reducing weed growth that results from broad watering. It lowers your water usage significantly, and (as mentioned above) does not require you to invest time every day or two watering, so is a huge time-saver!

Feel free to email me with any questions you have about how you might get started with any of the techniques or systems I’ve discussed above, or for more detail about starting a drip irrigation or rainwater catchment system.

My column appears every other Sunday in The Woonsocket Call (also in areas where The Pawtucket Times is available). The above article is the property of The Woonsocket Call and The Pawtucket Times, and is reprinted here with permission from these publications. These are excellent newspapers, covering important local news topics with voices out of our own communities, and skillfully addressing statewide and national news. Click these links to subscribe to The Woonsocket Call or to The Pawtucket Times. To subscribe to the online editions, click here for The Call and here for The Times. They can also be found on Twitter, @WoonsocketCall and @Pawtuckettimes.





The Call, Column 47 – HELP! What to Do About Critters in the Garden

6 06 2016

(May 22, 2016)

The Urban Farmer

HELP! What to Do About Critters in the Garden

A few days ago, I woke up for work in a great mood, like most other days. I put the coffee on and went outside to greet the day, peruse the garden, and feed the chickens. I was especially eager to check out the progress of one particular garden bed of brassicas (cabbage, kale, broccoli, and Brussels sprouts) and leafy greens that I planted a few weeks ago. And as I approached the bed, I found my plants…

…completely mowed down! Gone, eaten right down to the roots! It was most likely the work of the family of woodchucks that have lived in the wooded area behind my house for years, and have definitely visited my garden before. But it stings the same every time to find plants, especially those to which you’ve dedicated a lot of time and effort, just gone.

I’ll admit to having used a bit of colorful language after seeing this bad-mood-inducing sight, and imagining (at minimum) half-heartedly the proper way to hunt and cook those greedy little rodents. Don’t worry, I didn’t do it…yet.

Fittingly enough, that unfortunate experience was the inspiration for this column. High-time in the garden is quickly approaching, so we’re going to talk about the best “disruptive, but not destructive” methods to control critters in your garden. What I mean by that is to better define what I would generally call “sustainable” methods – ways to prevent wild animals from exercising their God-given right to eat plants they find growing in the dirt, that don’t contribute to the wholesale destruction of nature.

Now, we’ve talked about weed control before, but there’s something fundamentally different about pest problems and weed problems in the urban farm. As you all know first-hand, weeds are always there, but they don’t move nearly fast enough for you to wake up one morning to the unexpected sight of them having destroyed your garden. Animals (including bugs), on the other hand, are blessed with the gift of mobility, and they prefer the tasty plants in my garden over the grass growing right next to it for exactly the same reasons that I do. There are four loose categories of “disruptive, but not destructive” methods of critter control that we can and should all employ in our gardens. Let’s begin.

First up, there are biological controls. These use a harmless or less-harmful living creature to prevent an unwanted creature from visiting your garden, either by out-competing it, preying on it, or becoming its prey.

  • Planting trap crops: where a less valuable plant is used to lure insects and animals away from your food crops
  • Keeping a guard animal: whether a dog, a cat, or flock of chickens (not something I’ve ever tried myself), any animal that prefers the taste of insects and rodents over that of the plants in your garden does the trick
  • Encouraging wild bird activity: this seems counterintuitive, but by planting things that encourage birds, which may graze your plants but likely won’t decimate them, you are sure to keep harmful insect populations very low. This is sort of a non-domesticated version of guard-chickens.
  • Encouraging beneficial insects: introducing and encouraging ladybugs, praying mantises, and other beneficial insects, has the indirect effect of keeping harmful insect populations down. And my personal favorite…
  • Use poisonous or otherwise defensive plants: this can range from (simply) interspersing plants in danger of being attacked  with tomatoes/potatoes (whose leaves contain low levels of toxic alkaloids) or fragrant herbs (which tend to be deterrent to animals), to more sophisticated methods like taking advantage of wild-growing stinging nettles, which act sort of like a natural electric fence to unsuspecting animals, and even double as a tasty (cooked) spinach substitute since Mother Nature’s furry menaces probably won’t let me enjoy the crop I planted.

Next up, chemical controls, which use some chemical compound to deter or destroy a particular pest. I am generally hesitant to use these methods, because even so-called “natural” products can often be dangerous or polluting (poison ivy and deadly nightshade are “all-natural”). That said, naturally-derived pesticides like pyrethrum and retonone, and biological agents like bacillus thuringiensis, can be used as minimally-destructive pest control.

There are also ways to take advantage of some evolutionary quirk of the critter in question. For example, the urea-rich urine of predators (like foxes or human beings) literally smells of danger to small mammals, and can be sprinkled around your garden every so often as a natural defense mechanism. The same idea is what drives the use of fragrant plants, as described above.

Furthermore, there exist some truly harmless, natural chemical controls that I’ve used with a lot of luck in the past. Dried, ground chili pepper can be sprinkled on the soil to keep critters away: one accidental taste and I doubt they’ll stick around. Also, any type of fragrant onion (whether bits of garlic leaves, onion peels, or the inedible stalks of overwintered scallions) torn up and sprinkled in the garden seem to deter birds and small mammals.

There are also so-called physical controls, which utilize barriers and other contact-based mechanisms to prevent critters from eating your plants. Everyone knows the basics – fences, coverings like bird netting, wire mesh, and cloth, and any type of greenhouse/cold-frame structure – that are used to physically block animals (and sometimes bugs) from entering your garden. Furthermore, copper and table salt are effective physical (or maybe chemical?) slug deterrents, and open-topped containers of beer, buried with their openings flush to the ground, will attract, intoxicate, and drown all manner of unwanted bugs.

In addition, I would classify electrical-type phenomena as physical controls: a solar-powered electric fence is a great feature for an urban garden, and some companies make “gopher spikes”, which emit a high-pitched noise intended to deter rodents (a method that I actually believe I’ve had success with in the past).

When all is said and done, though, the best pest control is holistic management – plan your garden thoughtfully, and be willing to accept the low levels of damage that are usually inevitable.

By rotating crops, you prevent insect (and disease) populations from accumulating in the soil and confuse the radar of persistent rodents; by planting a good diversity of crops, one insect pest population or animal with particular tastes won’t destroy your entire garden; and by always having more seeds or plant starts than I need, I am able to reseed or replant (and replant, and replant) a bed with often minimal loss to long-term productivity.

In the end (and I assert this as much to myself as any of you), we can’t be mad at so-called pests. They live in nature, with no understanding of the human constructs of property rights and agriculture. They would prefer not to starve, and so when they see a plant that they like to eat, they eat it. Period.

I’ve said it before, and it’s even more apparent to me now: agriculture is by no means a completely pro-environmental pursuit. Nature would much rather “garden” that patch of land herself (doing so far more effectively) and feed her children in the process. We belong to the Earth’s ecosystem, not the other way around, and it’s up to us as responsible urban farmers to find ways to do our work that benefit both parties involved. And when it comes to critter control, the motto is simple: disrupt, but do not destroy.

My column appears every other Sunday in The Woonsocket Call (also in areas where The Pawtucket Times is available). The above article is the property of The Woonsocket Call and The Pawtucket Times, and is reprinted here with permission from these publications. These are excellent newspapers, covering important local news topics with voices out of our own communities, and skillfully addressing statewide and national news. Click these links to subscribe to The Woonsocket Call or to The Pawtucket Times. To subscribe to the online editions, click here for The Call and here for The Times. They can also be found on Twitter, @WoonsocketCall and @Pawtuckettimes.