Irrigation is crucial when it seldom rains, and drip (unlike spray) is an effective mechanism to keep plants healthy with minimal waste. But it has some downsides, and now in our 6th year of a drought and 3rd of rationing, a gardener can either get creative or crazed.
Drip is just that – a drip that flows downward. In sand, it goes straight down; in clay, it spreads slightly outward in an upside-down funnel. Even with multiple emitters on a plant, only roots by the drip get sated, not the entire root ball. And an irrigation zone typically services plants with varied needs, so some get more than ideal while others get less.
This past year I experimented with heretical techniques to counteract these limitations. This post shares the first success: totally remove drip to some species. Agaves, aloes, yuccas, euphorbias, and even some echeveria can actually do better with infrequent hand watering. Young trees can too. I plugged emitters on most of these succulents as well as on oaks, olives, and arbutus planted 3-5 years ago. Customized hand watering made these plants thrive and cut overall consumption.
Don’t get me wrong – drip is a blessing for many drought-tolerant species such as senecio and salvia. But those little drips twice weekly (the common plant zone setting) yield too much for succulents, too little for trees, and too frequent for both. Far better is deep watering once or twice monthly (or even less in some cases) for a few minutes as needed for type, location, maturity, and season.