Friday, August 31, 2007

General Emittence

Irrigation is an essential (though sometimes confusing, frustrating, or enraging) part of gardening. Without it, you might need fewer zen retreats but your plants will suffer and eventually die unless they're native to your locale. While this is a strong argument for growing native plants, it's not always what we want. So we make multiple trips to the hardware store, dig trenches, buy the wrong tubes and fittings, and employ some of the more colorful words we learned in school. In short, we install an irrigation system. Different types of irrigation are appropriate for different circumstances and different plants. One of the most efficient, drip irrigation, consists of watering at the root level with emitters that you yourself have placed along a central line of flexible hose which is connected to a water source. This source could be a series of valves if you are irrigating multiple 'zones' in your garden or could be as simple as a "Y" splitter placed on your house's spigot. The valve or spigot pumps water, at hours regulated by a timer system, through the hose and the emitters allow small pulses of liquid to escape and soak the roots of a specific plant. Tres cool, non? Gardeners use drip for irrigation in order to water right the root directly and not feed any surrounding weeds or boost your water bill. If a plant is too far off the main hose line, you can attach a thin black microtube and attach an emitter at its end--useful for any plants like potted stawberries or high-hanging window boxes making an appearance in your garden. In this same family of microirrigation are microjets. They can't break the sound barrier, but with a spray head instead of a drip head, they can efficiently and automatically water a larger section of plantlife, like a 4'x4' square area, or a tree with widespreading roots. The water only travels a short distance, so you're not going to lose much water to evaporation. Overhead irrigation is an alternative to drip and it means sprinklers, which is the common technique employed for watering a lawn or a largescale crop. Overhead is also a real winner in the Water Waste category. When you water at the root, the water is immediately soaked up by the soil and is not left to the wind or the sun's rays to be taken away. Even though it's a nice thing to do for your city's humidity levels, evaporation is one of the biggest drawbacks to overhead irrigation. The water is passing through the air in order to get to the earth, so it's pretty inevitable to lose water that way. Sprinklers are rated in gallons per minute while drip irrigation is rated in gallons per hour, which says a lot. So even though it's easier to plunk a sprinkler in the middle of your lawn and screw in the hose, it's a bigger waste of water and your money. On the upside: The gardener describes irrigation as merely channeling the water where you want it to be. Isn't that pretty? All you have to do is place your plants in the channel. Maybe irrigation is a zen retreat in and of itself...

Some of the stars of drip irrigation:

3 comments:

Polly said...

yipee - another posting!!

Polly said...

I like the play on words: General Emittence/General Admittance. A new one's born every minute (suckers on tomato plants). A mulch for all seasons. Abundant Solstice - although that one I don't quite get.

Polly said...

Time for late winter gardening info.