Veggie Garden Irrigation
I live in a weird climate for keeping a vegetable garden. We have very few days below freezing in a year, we normally get 2-3″ of rain per month year round, and the summers are brutally hot and humid. Now, the low amounts of frost mean we can theoretically grow things under row covers during months when usually gardens may go fallow, the early and extended growing season due to warmer springs and autumns means we can produce an absolutely overwhelming amount of food, while the heat and humidity mean pests and needing to provide shade for crops that you usually would give 12+ hours in the sun.
Theoretically, the sheer amount of rain would mean we wouldn’t need to water the garden too often. This does not work in practice. The heat rips the moisture out of the soil and all sorts of plants wilt in hours under the brutal sunshine, and though the rain comes down in buckets, it’s becoming more and more common to get one rain day of 1-2″ every few weeks rather than lighter rain days more frequently. All of this adds up to needing to water our vegetables every single day before the sun has risen so their roots can soak up whatever they can before it all evaporates.
Now, I love gardening, but I hate watering. I hate standing out there with a hose, trying to remember how long I need to stand at each bed spraying the ground and hoping the soil won’t bounce up and infect my plants with some fungus that means our harvest will be decimated. Added to the fact that surface watering is less effective, I knew I’d need to figure out drip irrigation for our beds.
I thought I’d manage it last year, but I never got round to it. This year I was determined, first because it wasn’t even April and the temperatures were soaring–our heat-resistant lettuces bolted before my birthday this year–second, because I’ve become increasingly interested in sustainable practices in the garden, and conserving water would be an ideal way to do this, especially as growing our own veggies helps us reduce our grocery bills as well.
After a little bit of research, I found that I’d need to connect to an existing irrigation head right next to our first garden bed, convert it to a drip line head, and lay out 1/2″ black irrigation tubing to get the lines where we needed them. From there, it would be 1/4″ drip tubing with 1 gallon per hour built in emitters laid out flat on the beds and paths, and small drip emitters for any of the potted plants–like our peppers, berries, and potatoes.
It was an adventure in digging up hard dirt, what felt like half-a-dozen trips to my local home improvement store to replace parts I didn’t know replacing or getting more of something I was sure I had enough of the last time. Add in the distractions of some fun native plants and figuring out how to rig up an emitter to fill up our bird feeder, and it took a grand total of two weeks to get everything settled. There are still finishing touches to be done–adding top soil to cover some eroded spots where I needed to dig to find the irrigation lines (as well as covering it with erosion fabric), adjusting a few emitters that don’t work quite right, and some additional sections of the yard that need some irrigation heads swapped out, we’ve got a working irrigation system!
I will say, when I need to do this again, I’m going to do it differently. First, if I can passively irrigate my crops, that’s what I want to do. There are many ways to passively irrigate, including buried clay pots–ollas–that allow plants to pull water into the soil as needed. We’ve got a few of those buried, but their effectiveness is hard to judge so far. Manually filling is the most common method, but even these can be hooked up to irrigation systems that fill them up automatically. Building berms or catchments into a garden to allow rainwater to collect is another way of increasing passive water collection, but with raised beds, I didn’t consider this option. Other methods include deep pipe irrigation–again, manual or automatic are both possible–wick irrigation, and supplementing with water collected in rain barrels.
Second, if irrigation piping is still necessary, I would insist on setting the garden on a different zone from any lawn sprinklers. Our current system is set up such that our backyard sprinklers must be on while we’re watering our garden. I’m not much of a person for lawns–grow food, not lawns, people–so watching the sprinklers water ground that produces nothing but grass is disheartening. We’ve already planned to dig up the heads and swap them out with new versions that will allow us to cap them off, but my first choice would have been separate zones entirely.
Coming up next in garden projects–adding shade cloth tunnels so our plants can benefit from less direct sunshine. It sounds counterintuitive, but I’ve seen results already; we’ve been trying to grow potatoes for three years and haven’t gotten a single crop. I decided to move the potato bags into the shade provided by our fence. The potatoes benefit from the morning sunshine, but during the hottest part of the day, they get shade. Wouldn’t you know it, we’ve got potatoes growing well enough that this is the first time I’ve seen them in flower. After that, I believe it’s rain barrels, then re-wilding the fence line with natives of all kinds of varieties to bring biodiversity back to our yard–enough so that maybe the birds will start plucking the caterpillars off our blueberry bushes and feeding them to their nestlings.