2 years ago I reduced my sprinkler interval (from 3x) to 2x per week for both lawn and garden. It think I could go to 1X per week for the garden, but not the lawns (double dwarf fescue). This seems to make more sense for sprinklers (as long as there is no runoff) than for drip.

On my drip systems I have been going the other way - from 1X or 2X per week; to every day or every other day. This based on information that evaporation loss is not as significant, and that most roots and soil fertility are in the top 6 inches of the soil.

Chad

That's because there are several FACTORS that influence a realistic, effective and efficient watering schedule:

-- Soil texture: clay, sand -- field capacity and capillary action.

-- Plant species -- xerophytes, mesophytes; origins: "Tropical/Subtropical", "Desert", "Mediterranean"
-- Plant growth cycles -- actively growing, resting/dormant

-- Plant size/age -- for small plants consistency is more important than quantity. You do not want the plants to go dry/wet/dry over and over again. Up to a point -- BIG plants develop drought-resistance.

-- Mulched or not -- type, quantity, and quality of mulch.

-- Weather -- Water less often when it’s: Rainy, Cool/Cold, Humid, Cloudy, Short days, low sun.

-- Water more often when it’s: Windy, Hot, Dry

When it comes to actually applying water, there are five critical principles:

1) Always check your soil for moisture and look at your plants before you water.

To check the soil around new transplants and in vegetable and flower beds, dig down a few inches with your fingers or with a trowel; if the top 1 to 2 inches are dry, you probably need to water.

In lawns or around established trees and shrubs, use a soil sampling tube.

Leaves also can tell you when it's time to water. Most will look dull or roll in at the edges just before they wilt.

2) Water deeply and infrequently rather than shallowly and frequently.
Frequent, light waterings will encourage shallow rooting, causing plants to suffer more during dry periods. Light waterings "tease" the plants.

MYTH: Plant roots can find water.

Plant roots grow IN soil that is moist. They must have water to grow; they do not grow where there is no moisture. At least not for long. And they do not have some kind of "radar" or "sense" to find moisture. In other words, roots grow where you put the water.

Deep waterings truly "train" roots to grow deeply.

3) Apply enough water on the surface to soak the entire root zone AND THEN SOME.

Theoretically, a plant’s "root zone" extends to the "Drip Line".

Especially when watering young trees and shrubs, water up to and just beyond the drip line. WHY? To encourage roots to grow beyond their given space.

As plants mature, of course, their roots grow farther out into the soil, eventually extending well beyond the canopy and the berm you’ve built. To water growing plants adequately, you'll need to make a wider basin (for flood irrigation) every few months. Or move sprinklers, soaker hoses, and such outward.

Thorough watering occurs just before a puddle appears on the surface of the soil and does not soak in.

4) Water in the morning

Less water lost to evaporation than during the heat -- OR WIND -- of the day.

Do not water in the evening – it raises the humidity.

Myth: Watering during the day can burn plants. Myth: the sunlight is magnified by the water drop on the leaf to cause a leaf burn. If this myth were true, all gardeners would cover all their plants prior to every rainstorm. Farmers would not be able to prevent widespread "leaf burn" after rain clouds gave way to sunshine. Forests would explode into a blaze at the first sign of a rainbow.

Hosing off plants is actually a good thing.

There’s a related Myth: water on the foliage causes mildew. Mildew is NOT caused by "free water". It is promoted by high humidity – moisture in the air. More specifically, cool moist nights and warm days.

FINALLY,

5) When in doubt, DON’T water.

Joe

Thanks for the tips, Joe. I always wondered how the Algerian ivy that covers our chain-link against the asphalt driveway that NEVER gets watered... somehow gets mildew!
Renee

I don't have any plants in the sun in small pots or truly "raised" beds, though.

Given that assumption, and that I am clever enough to change the amount of water (0% - 100%) with the seasons etc., it seems a reasonable plan.

To be clear, I want to try decreasing the sprinklers for garden areas (think mixed border) from 2x per week to 1x per week, with a corresponding adjustment in duration.

Secondly, for those already using drip, are you using a long interval (1x-3x) or a short interval (every day or every other day).

I have tried both to little noticeable difference, though the long interval makes it hard to establish new plants in summer.

As an aside I am slowly converting from the flag type drippers in 1/2" pipe (ala home despot) to the inline drip "Techline" from Netafim. I really think the Netafim is a superior product and worth the extra $.

1) I would never offer a watering schedule to anyone If I didn't know what kind of soil they have, what kinds of plants they have, etc. I'd be afraid you'd underwater or overwater or otherwise not get it exactly right.

2) No one has your exact conditions and if I provided you with a watering schedule here, I'd be afraid that someone would duplicate that schedule assuming it was universal.

Joe

1) Researched and read for a year before doing any work. Although I ended up with a lot of plant substitutions, I tried to keep 'like to like' - meaning water-lovers grouped together and kept to a minimum.

2) Our lot is on a hillside, so even with adobe clay the drainage is good. But the clay was really hideous, so on almost all the beds (I have 15 separate beds divided by various walkways, patios and driveway) we had the first 6-8" dug out, tossed in the furthest part of the backyard, and replaced with good quality compost. After 6 years the clay is slowly returning, but most plants are well established and seem to like the base.

3) I use soaking hoses and mulch heavily. Depending on the heat - we are in the Oakland hills so a little cooler than you, still within the edge of the fog belt - I water no more than twice a MONTH. If we get a heat spell, then once a week in two extra-thirsty beds. If it's cool and foggy, I can go 3-4 weeks without watering.

We have no lawn at all. I'd rather have flowers and foliage: more interesting, more colorful, and actually much easier to take care of.

Joe, I am not looking for a recommendation so much as getting a feel for what others are doing. My own soil is not clay, but more of a stony silty loam.

every third day for an hour for most plants
every fourth day for the shrub border/ drought tolerant plants

Things grew well, but when they moved them as I was getting new hardscape-the roots on the plants I dug up seemed very shallow.

Marie louise, I think jkom is in your area. The root depth can depend on the plant, too. If your plants looked good, I imagine they were getting enough water. Some of my shrubs don't get any real water at all once they are established, though. Podocarpus, oleander, ivy- all of that stuff grows without direct irrigation here.

Renee

Your garden plants are so well designed and look so wonderful. It has been a couple of years since I started to take interest in my garden but it has been such an uphill battle to fill all the areas (I have 2 kids and that takes most of my time). If possible, I would appreciate it if a layout of your plants could be posted.

Thanks,

Purnima

purnima, I'm sorry, I don't have an updated layout of plants. The one I have is from years ago and it's way out of date.

marie louise, hosenemesis is quite right that root depth depends on the plant. I'm always moving plants around and some of them pop out of the ground easily. Others, like roses, oleander, tagetes, etc. - are killers to move or pull out.

The few water-thirsty plants I have are rhodies, azaleas, and hydrangeas. I have a "Flaming Embers" hydrangea I deliberately put in a spot where excess bed runoff drains, and I've found even in summer I never have to give it extra water.

But almost all plants respond best to deep soaking, good drainage, and letting the soil dry out a bit before watering again. Lots of humus or compost makes a huge difference in getting plants established well. Good soil really holds water - in the single bed where I did not replace the soil, I have to water twice as often as the other beds.

Despite the current conventional wisdom of "let the plant get established in the soil you have", those plants where I did not prepare the soil well, are noticeably slower to become established.

The one exception: plants that like lean soil or little fertilizer.