Thursday, July 16, 2009

An Automatic Watering System Saved My Garden

Water is vital to a garden. Too much or too little water can affect your plants considerably. This is one of the great advantages of SIPs (sub-irrigated planters). The water variable is pretty much taken care of – as long as the water reservoir stays full and the potting mix does not dry out, your plants get just the amount of water they require.

This theory is all well and good if you’re around to fill the water reservoir. In the summer heat, large plants can easily use an entire reservoir of water, sometimes two. If you plan to travel at all; you’ll need a back-up plan.

Some people use irrigation drip methods, timers, or even a Hudson valve in a central water reservoir. All of these applications can work and I looked into them for my system but fortunately, Earthbox took away some of the guessing and work with their proprietary system.

Here’s where the Earthbox’s Automatic Watering System (AWS) saved my garden. I installed it a few weeks before two back to back weeks of travel – one for personal and one for work. I knew I wasn’t going to be around and needed something to get water to my plants.

I have 12 boxes and Earthbox sells a 12 box kit for $160.00. Seems a little expensive but I took in account trying to piece something together and the time it would take and thought it was well worth the price. The kit includes one regulator, 12 sensors with fill tubes, eleven black t-connectors, one white t-connector, two reducers, 100 feet of ¼ inch tubing, and 25 feet of 1/8 inch tubing. The instructions were pretty minimal but it was easy enough to figure out. This system is expandable to up to 30 boxes.

First, I installed a splitter on my water spigot so that I could have a dedicated line to the garden. I used a 25 foot RV hose, which is safe for potable water, and attached the regulator to it. I made sure to raise the regulator so that it is higher than the sensors on the boxes (picture).

Then, I ran the ¼ inch tubing along my boxes, cutting wherever I needed a break and installing a black t-connector. Then I connected the 1/8 tubing from the t-connector to the sensor that sits in the fill tube. The sensor works on pressure. If the tube is in the water, it’s happy. The moment the water level drops, the circular sensor on the top of the fill tube drips water into the box to the desired level. It’s that easy.

One thing I learned along the way was that you should use hot water to soak the tubing before attempting to install t-connectors. The hot water softens the plastic and allows you to fit the tubing over the barbed part of the connector. Once connected, the tubing cools and shrinks over the connector, forming a water tight seal. The instructions recommended oil or petroleum jelly but I would recommend against that since the ends could end up being too slippery to work with.

It works great and I don’t have to worry a bit about over or under watering, especially when I’m out of town. Another added benefit is that you won’t waste one drop of water. How’s that for conservation?


H2 said...

Nicely done, Russ. It's great to see your garden too--looks like it's producing beautifully.

Erik said...
This comment has been removed by the author.
Erik said...

Hey Russ how's it going!
Just wanted to thank you for doing a great job on the site and for sharing all the useful information. You inspired me to make my own rooftop garden here in Chicago. I'm documenting my experience on my blog
I hope that my garden works out as well as yours!

Russ C said...

Thanks for the note. Keep us posted on your progress. Checked out the blog and it looks like you're off to a great start - I like the newspaper idea for seedlings. Hopefully, some of the info here has given you a little insight. We've learned a lot over the last few years so we're hoping people find it helpful.


Dadda said...

I'm looking to piece together a drip irrigation system on a timer to handle 7 bucket SIPs on a row house roof in DC with inconvenient access (think overly curious 3 y.o.). Now that you've seen the earthbox proprietary system, do you think you could (and recommend) buying all the pieces and doing it yourself? Without enough reading, I ordered all 1/2" tubing and T connectors dropping the 1/2" tube down each watering tube. The water didn't make it past the second down spout! (Whoops.) your post and the earthbox system gives me hope but I'd love to do it cheaper. Thoughts?

Bruce said...

Hi Dadda,

Russ, who wrote the original post and was using the official Earthbox watering system, isn't writing for the blog now. Maybe I can answer your question.

It sounds like you've got the right idea with the 1/2" tubing and connectors. I'd say your problem is the short lengths of tube that lead into each planter are 1/2", not 1/4" tubing. There just isn't enough water being supplied by the main supply line to allow for 1/2" tubing to go to each bucket. Also, you can only supply 10 or so 1/4" 'whips' from each 1/2" main run. Add up the cross sectional areas...

Maybe H2 has something to add.

Dadda said...

Thanks Bruce. Seems that I can get away with a 1/2" supply line if I have 1/4" down spouts, with a limited number of buckets served. It looks like the earthbox kit uses a 1/4" supply with 1/8" down spouts (whips). I could go that route and just eat the 1/2 tubing, basically starting over.

Also, does anyone know anything about the sensors in the earthbox kit?

Bruce said...

Dadda -- the sensors in the EB kit are similar to toilet floats. They are inside of roughly 1.5" diameter tubes that are equal in length to the height of an EB (making it difficult to retrofit them to any planter not the height of the EB).

Russ C said...


Russ here. Just saw this and thought I would add my 2 cents. From what I recall (I now live in MN), Bruce is correct on everything he noted about the EB watering system. It worked really well for me but may be difficult to retrofit to the bucket SIPs. If you do try to mimic the EB system, please note that there is a regulator at the start of the irrigation system and it is placed higher than the highest "float" sensor. This is pretty important. Bruce may have already tried to retrofit the EB system but if not, you may want to try their forum for any other ideas. Best of luck!