Did You Know? ET-Based Irrigation Controllers

et-based irrigation controllersET-based irrigation controllers? When you hear that you may think back to the early 80’s when E.T. was all the rage. But the ET I’m referring to has nothing to do with phoning home. ET stands for evapotranspiration. Evapotranspiration, as defined by the Irrigation Association, is the loss of water from the earth’s surface through the combined processes of evaporation from soil and plant surfaces, and plant transpiration. So what does all of this have to do with your irrigation system? Simply put…everything.

If you have an irrigation system in your garden you should be concerned with evapotranspiration. When you set your irrigation timer to water Monday, Wednesday and Friday for 30 minutes on each zone, your system will water the same whether the temperature is 70 or 90 degrees, whether there is a light breeze or 20 mph wind, whether the humidity is 40% or 90%. Unless you have a rain sensor on your system (which you should…they can be installed by a professional for less than $100), your system will water for 30 minutes if it rained 1/10″ or 2″ earlier in the day. What if you could have a controller that would take all of that into account and then water based on your plants’ needs. You can with an ET-based irrigation controller.

Hunter makes a very nice ET-based irrigation controller that I have personal experience with. Other irrigation manufacturers, including Toro, Rainbird and Irritrol, make ET-based irrigation controllers but I can’t speak to the quality of those controllers since I don’t have any experience with them. With the Hunter ET-based irrigation controller, you have your own weather station that records real-time data and converts all of that information so that your plants receive the water that they need. Here’s what it looks like:

hunter ET-based irrigation controller

It has a rain gauge, an anemometer that measures wind speed and a thermometer to determine the temperature at your specific site. When setting up the controller, you enter the following data that helps the computer determine when and how long to water:

  • Soil type
  • Slope
  • Crop being grown
  • Age of crop (new vs. established)
  • Sun exposure


This information is critical and the ET-based irrigation controller is only as good as the information that is entered at this stage. It is very handy to be able to enter different information for different zones according to their site conditions. Most landscapes have some sun and some shade, some turf and some landscape beds and some new plantings intermingled with the older ones. By entering and updating the information as conditions change, the controller is able to adjust the watering times and durations accordingly. Pretty cool huh?

So what does all of this cost? Well, that depends. If you already own an irrigation controller that is compatible with the ET-module, the cost is very reasonable…you can buy the module without the anemometer for the Hunter ET-based irrigation controller for $239.07 online. The anemometer is about the same price…so maybe you take baby steps in converting your existing system over….the choice is yours. While the upfront cost may turn you off initially, you should do the math to see how long the payback takes. Many localities are now charging a higher rate for water usage over a certain limit, aimed at users with irrigation systems. If you live in suburbia and have to pay sewer charges, the payback will likely take far less time unless you have a separate meter for your irrigation system. Also, consider the benefit of set-it-and-forget-it. No more adjusting your watering program when the temperatures soar to 95 degrees…the ET-based irrigation controller will adjust the watering times for you…yeah!

Of course, if you’re like me, my irrigation system is in the sky and it is completely at God’s will. If the rain doesn’t fall on my landscape, the plants don’t get watered. They’ll either live or die trying. My only exceptions to that rule are newly transplanted plants and vegetables. Since I don’t have a veggie garden at my house due to the abundance of shade, I don’t have that concern for now. Consider hugelkultur if you will be installing new beds in the future. It’s a way to garden without watering at all. That’s my kind of garden!

Let me know your thoughts about ET-based irrigation controllers…leave me a comment below or e-mail me at stacey@midatlanticgardening.com. Happy gardening!

Friday Free For All: Using Water Wisely

Well, it’s happening already. The Mid-Atlantic gardening region is dry. Granted, we have 1″-2″ of rain expected this weekend but the rain has been pretty negligible in central Virginia since the middle of March. I hope that this isn’t a sign of things to come this summer. My mind has been churning about how much water we use. Not just my family or community but as a nation…as a world. Water is a renewable resource but that doesn’t mean that we can use it with reckless abandon. Let’s delve deeper to look at how we can use water more wisely in our gardens.

  1. Hugelkultur – if you’ve been reading my posts for a while, you know that I am big fan of hugelkultur. It just makes sense…use wood that nature has provided for us to help plants through the dry spells. Check out the link for more information if you’re unfamiliar with the practice of hugelkultur.
  2. Reduce your plants dependence on irrigation – while it is vitally important to make sure that newly transplanted plants are watered until they can get their roots in the ground, it is generally not necessary to water them for the rest of their lives. We had an extreme drought in 2010 here in central Virginia and emergency water restrictions were put in place; those restrictions meant that you couldn’t water…at all. One of the reservoirs that feed our public water supply, Lake Chesdin, was all but reduced to a pond. It was truly an amazing sight to see. During that drought, guess how many times I watered, even before the emergency water restrictions were in place. Zero. Zip. Nada. I am of the mindset that my plants will either live or die trying. I don’t have the desire or time to water them regularly. So do you know what they do to compensate for my lack of interest? They send their roots further into the ground to search for their own water. For the record, I didn’t lose one plant during the drought either.

    using water wisely

    Lake Chesdin 2010 Photo courtesy of Richard MacDonald

  3. Water wisely – for those newly transplanted plants, get creative with your watering. For trees, water slowly and deeply to make sure that the rootball is being wet thoroughly. You can accomplish this in several ways. One way is by using a treegator. These are available in either donut shapes for multi-stemmed trees or upright bags that zip shut around the tree trunk. You fill them with water and the water drips out slowly and wets the rootball. If you want to make your own cheap tree gator, get a few 5-gallon buckets and drill tiny holes in the bottom. Set them around the base of the tree and fill them with water. The water will trickle out slowly and water the rootball. You can also just let the hose run at a trickle for a half hour or so at the base of the tree.using water wisely
  4. Mulch – mulching your garden will help to reduce evaporation and regulate soil temperature, both of which will reduce your plants need for water. Mulch should be applied 2″-4″ thick. If you apply it thicker, you will reduce the amount of oxygen that is penetrating into the soil and that will impair the plants’ root growth. For heaven’s sake, don’t end up with mulch volcanoes around your trees!
  5. Apply compost – this is such an important part of using water wisely. By adding compost, you are improving soil structure. By improving your soil structure, your sandy soil is able to hold more moisture and your clay soil begins to open up to allow water in. Adding compost is the magic ingredient that makes all of the other items we discussed today possible.


So what will you do in your garden to use water wisely this summer? There are many other ways to reduce your water usage and I’d love to hear what you are doing. Leave me a comment below or e-mail me at stacey@midatlanticgardening.com. Happy Friday and happy gardening!

Did You Know? Hugelkultur is a Way to Garden Without Watering


Happy Monday to everyone! I’m really excited about today’s post. It deals with hugelkultur, which is a way to garden without watering. Let me start this conversation by giving you two links that can provide a more thorough explanation regarding this way of gardening. The first is from Paul Wheaton (he’s hilarious by the way) at www.richsoil.com. You can find the direct link to his hugelkultur article here. The second link is from Jack Spirko at The Survival Podcast. Here is a link to a podcast that he did about hugelkultur. Without these two men, I would have never learned about this way to garden without the need for additional water.

The brief story of hugelkultur goes like this: you can either dig down and put logs in the ground or stack logs on top of the ground. Either way, you add soil and compost to the top and then plant…that’s it! The rotting logs hold moisture and keep it available for when the plants need it. Have you ever walked through the woods, even in a drought, and noticed a rotting log? It’s full of moisture and that’s the key to the success of hugelkultur. Sometimes the most difficult problems can be solved by the simplest methods and this is one of those times.

This weekend, my family partnered with the Taylor family to build two hugelkultur beds for our joint vegetable garden. This will be our third year gardening together and the Taylors are always willing to try new ways of gardening. Last year we built six 4’x4′ square foot gardens and they were a wonderful success. I just know that the hugelkultur beds will be a blessing this year! Let’s dive in to the pictures!


This is how the bed looked before the sides were put on



The beds are approximately 19" deep and they are 4' wide by 17' long



Here's the construction zone where the men were constructing the sides and ends




The kids thought that the area made a great place to ride bikes and play...who can blame them?



Putting the sides on the bed



And the ends...



Here are the kids again...there's Maya, Maddie and Myles. Maddie and Myles are our two little dirt loving kids



The first logs are getting ready to go in the bed...exciting!



The bed is full of rotting logs that will provide moisture for the vegetables that will be growing there this summer



Once the logs were in place, we covered them with a layer of garden soil



The beds are ready for compost! We were fortunate enough to have access to horse manure from a neighbor



Here is the bed with a full layer of compost



We added a top layer of garden soil...we would have mixed the soil and compost but at this point it was raining



Here is the finished product...for the day anyway. We completed two hugelkultur beds



Here are the beds from another angle


I forgot to mention that the total depth of the beds is 3.5′. If I were a plant, I’d like to live there! I am very excited about the veggie garden for this summer. I want to thank Sean and Anna Taylor and my wonderful husband Ed for all of their hard work. Sean obtained all of the wood that we used for the beds from old horse fencing, him and Ed built the wooden bed frames and Anna watched the kids when it started raining. I also need to thank Tyler Shumate for helping us obtain the composted horse manure…if there was one earthworm in the compost there were a million! If we have a summer like last year where it seemed to rain every other day, we won’t be able to tell how effective the beds are. But something tells me that this summer will be a typical Mid-Atlantic gardening summer where drought prevails. If it does, I am hopeful that these two beds will be able to survive the season with no additional water. I’ll keep you posted! Let me know your thoughts by leaving me a comment below or e-mailing me at stacey@midatlanticgardening.com. Happy gardening!


February 6, 2012Permalink 8 Comments