June 11, 2011

Credit: Liza McCorkle, istockphoto.com

I’d rather have rain irrigate my tomatoes. It’s much easier and I wouldn’t mind a change of plans because of a rainy afternoon. So it was in my Massachusetts garden when I would welcome a good summer thunderstorm. For twenty years now I’ve been a SoCal gardener. Summer rain isn’t typical in our Mediterranean climate so I have devised other ways to water my garden.

Many edible gardeners in California use drip irrigation. Unfortunately, when we built our raised beds, we didn’t make provision for this. I’m not sure a drip system would work well with my gardening style.

If tomatoes are in rows, they can be irrigated in a more traditional way.Tomatoes are usually placed in a staggered fashion in my 4 by 8 foot raised beds. Traditional rows aren’t the most efficient way to irrigate tomatoes grown this way. Row irrigation also uses more water and wet soil between the plants gives weeds just what they need.

Some years I’ve used soaker hoses in the raised bed of tomatoes, covering the hose with lots of mulch. It does concentrate the water to the tomatoes and keeps water off the leaves. I’ve not always been satisfied that the water goes deep enough to draw the roots downward.

What has worked for me in recent years is sinking a plastic gallon nursery pot in the soil next to the tomato plant.  Between two plants I sink a two gallon pot. I still water around an 18 inch basin for each plant, but the buried pot sends the water deep where I want the roots to go.

I decided to try a variation on the above method by sinking an unglazed clay in the soil. I put a rubber stopper in the bottom hole and covered it with an old plate to prevent evaporation. The theory is that the water should slowly seep into the soil and irrigate the tomato plants. It’s not working for me. Maybe I need a more porous clay pot. Perhaps the soil has enough moisture, as I’ve been watering the newly planted tomatoes. It’s been two weeks and no drop in the water. Anyone had any experience with this method? 

Read more about ollas, an ancient irrigation technique with application to water-wise gardens. Watch a YouTube video on using ollas.  Purchase an olla here.