Ask a Master Gardener

photo of irrigation controls at Seed to Supper Farm

Watering the Garden

8/13/24

Let’s face it, being a vegetable gardener in August is brutal. Maybe it feels a little more brutal after just having come out of July, or maybe it’s because I just showered after about 4 hours at our Seed to Supper Farm this morning, but dang… it’s hot out there. But even though it’s hot, there’s still a lot to do in the garden and one of the primary things we need to do is keep those plants irrigated.

At home, I am historically a hand waterer. I just like to get out there with the water wand and give the plants a little individual attention. It’s a good way to not only make sure the plants get enough water, but also a great way for me to keep an eye on things so that I can catch any insect or disease issues early.

That being said, I am looking at tapping into our sprinkler system so I can run some small irrigation hoses to each of those hanging pots, so I don’t have to bake out there in the sun while watering. This will be a winter project for next year. I’ll just be able to turn on the water and watch everything get what it needs from the comfort of our house. Who knows, maybe I’m just getting old, but the idea of this is quite appealing to me right about now.

The good news is that after a little online shopping, it looks like adapters, hose, and sprinkler emitters will not be a big investment. So, in the near future I’ll be putting my order in and getting ready to do a little backyard, outdoor irrigation hookup. To make it even better, I’ll probably get one of those water shut off valves that can be controlled by my phone so I won’t even need to get out there to turn it on. Yup, I’m getting old.

At the Tulsa Master Gardener Seed to Supper Farm, we have invested in a legit irrigation system. Fortunately, we have access to wells for our water source. Otherwise, I hate to think what our water bill would be each month.

For our primary growing area, we have a 2” water line that feeds through a back-flow valve, a filter, and a water pressure meter. In addition, we can turn a couple of valves to force the water through a Venturi fertilizer injector so that we can use our irrigation system to not only deliver water, but also push fertilizer out to the plants.

For the average home grower, this might be a little excessive, but it sure helps us out at the farm. After the water makes its way though all those valves etc, it makes its way to the individual rows through what we call blue lay-flat which is a 2” inch in diameter, flexible hose. From there, we insert valves into the lay-flat which are then connected to drip lines that runs the length of the row under the black plastic mulch. It’s a great way to deliver water and nutrients exactly where they are needed as well as helping to conserve moisture under that mulch. It works great for us, but this may be a bit much for the average home gardener.

For the home gardener, the first option in the irrigation food chain would be overhead watering from our home sprinkler system. While these systems are probably already in place, it’s not the best for vegetable gardeners since most of the water is delivered from overhead. That being said, that’s what many gardeners have so that is what we make work. The challenge with overhead watering is that the water is primarily delivered to the top of the plants rather than to the roots. This becomes more problematic for those who water in the evening because it keeps the plants wet overnight and wet plants make it easier for disease to take hold and then spread. A better plan is to deliver the water at ground level where the roots are.

The easiest way to utilize a root only watering system is to purchase a soaker hose and weave that soaker hose around your plants. When using a soaker hose, you can turn on the water and let it gradually feed out into your garden. The slow delivery of water from a soaker hose helps the water sink deeper into the ground so you don’t lose it to surface evaporation or run off. Deeper watering also encourages the roots to grow more deeply, making them a little less susceptible to variations is water availability.

While soaker hoses are good for smaller gardens, OSU irrigation specialists have told me that the quantity of water delivered at the beginning of the soaker hose and water delivered at the end of the soaker hose will not be equal. So, while this is a good solution for smaller gardens, it probably won’t be the best for larger gardens.

Next would be drip irrigation hoses. Drip irrigation hoses are made from a stiffer, more hose-like material. To put one of these together properly, you’ll need to get some hose and fittings to make the corners and connect to your water source. But the hoses can be purchased with drip holes every foot, 18 inches, or 24 inches etc. so you can line up those drip holes with where your plants are. Yes, it’s easier to do this before you plant that after.

And then there are a variety of systems using supply hoses and small emitters. These systems work really well but do require a little bit more in the way of connectors and emitter heads to make them work properly. However you decide to proceed, I’m going to be leaning into installing a better system at home so I can watch it work from indoors during the months of July and August. See you in the garden.

You can get answers to all your gardening questions by calling the Tulsa Master Gardeners Help Line at 918-746-3701, dropping by our Diagnostic Center at 4116 E. 15th Street, or by emailing us at mg@tulsamastergardeners.org. Photo: Tom Ingram