The Right Way to Water Your Lawn and Garden

Improper watering is the number one cause of plant failure. Knowing how wet the soil is at the root level can help you keep your plants healthy. 

Keep in mind: different plants have different watering needs. Learn those needs, then group plants together with similar watering requirements. The Sunset Western Garden Book is a good source for that information.

Signs of not enough water at the root level of plants: 
Wilted leaves in the morning.
Red-brown margins of leaves.
Premature fall color of leaves.
Growth reduction.
Leaf drop.
Branch dieback.

Signs of too much water (also called aeration deficit) at the root level of plants:
The soil has a foul smell, like rotten eggs.
Soil is a blue-gray color.
Yellowing, wilting and/or dropping of leaves.
Limited new growth.
Small, corky outgrowths on the undersides of leaves.


Be warned, though: sometimes, symptoms of overwatering and underwatering can be the same (such as leaf wilting). And, symptoms of soil water problems may actually be another problem...that was caused by the watering problem! Root rots, for example, thrive in saturated soils.


Frequent, light watering leads to shallow rooting, increasing the chances of plant problems.

To determine the amount of water at the root level:

• A day or two after watering, dig down 8 to 10  inches with a trowel or small shovel, near the drip line (outer canopy) of the plant. Doing this in two or three spots would be more helpful.

• At that depth, grab a handful of the soil. Squeeze that handful. If it is muddy and watery, reduce your watering for plants that require regular (but not frequent) irrigation. If it is so dry you cannot form a clod in your hand (it turns to dust instead), increase your watering (for those plants that require moderate amounts of water).

• If you can form a dirt clod in your hand, yet break it apart with a little effort, that is probably the correct soil moisture for your plant.

• Steve Zien, owner of the Citrus Heights-based organic landscaping consulting service, Living Resources, recommends the use of a soil sampling tube to determine the moisture at root level. "Just press the tube down six to eight inches into the soil after you are done watering," says Zien. "When you bring it back up, the open slot along the side of the tube will let you see if the soil at that depth is wet, moist or dry. Adjust your watering time so that the soil sample is moist, not too wet or dry."

• An easier, but more unreliable way to measure the water content of the soil: purchase an inexpensive (under $10) moisture meter. Test its accuracy by putting its probe into a glass of water. If the probe does not read "wet", choose another. Expect it to function for only a year or so.

• Battery operated moisture meter probes may set you back a few more dollars, but in my experience - with proper care (clean them after each use, don't leave them outdoors) - they will last many years.

 

• Extended, infrequent, slowly applied irrigation is the most efficient watering method. Soaker hoses or drip irrigation systems work best. Here in the Central Valley, foothills, and Bay Area, run them for 3 to 6 hours at a time, twice a week, in the summer. This is only a guideline to get you started. Adjust that timing to your particular soil type and plants.

• And, don't forget: add more drip emitters and drip lines as the plant grows, especially for trees and shrubs. Make sure to get water to the outer canopy of the plant (and beyond) where the roots travel.

How much water does your lawn need? 

Some tips from the UC Integrated Pest Management Website:


• Avoid planting turf species that require frequent watering, such as bluegrass or ryegrass.
• Design your landscape to minimize water runoff onto hard surfaces and into storm drains.
• To reduce runoff, install non-irrigated buffer areas, which include water-efficient plants or permeable features, next to sidewalks or on slopes.
• Aerate heavy or compacted soils, so water can easily move down to reach grass roots.
• Install an irrigation system that you can adjust to properly water areas of your landscape that have different requirements.
• Water only when your lawn needs it.
• Water requirements vary according to turf species, location, and month of the year.
• Most lawns need water when the top 2 inches of soil have dried out.
• Shady and sunny areas and different soil types will have different water requirements.
• Deeper, less frequent watering is best for most lawns. Water only 2 to 3 times a week.
• Make sure your sprinkler system isn’t producing runoff, especially on slopes. If you see runoff, use shorter watering times and repeat the cycle to allow time for the water to move into the soil.
• Water early in the morning when evaporation and wind are minimal.
• Adjust your watering schedule seasonally, and shut off your irrigation system during rainy weather.


And, the video: How Much Water Do Your Plants Need?

It's the Silly Season for Garden Pesticide Advertising

 It's spring and the "Silly Season" for garden product advertising is in full swing. And gardeners want products that are safer to use for everyone concerned: their families, pets, plants and beneficial insects. Advertising has drilled that into their heads. Unfortunately, many are pushing products that have been around awhile; they're just dressed up with new names, prettier labels and buzz words that mean little. "Natural", "safe to use" and "earth-friendly" are three popular, but useless label stickers currently in vogue. We tackled a few of these products in an earlier blog entry this year.

Don't pay too much attention to the advertising. Read the entire product label before purchasing. And then follow those label directions. And don't believe the big print or the name of the product on a garden pesticide. It's the small print, the "Environmental Hazards" and "Precautionary Statements" that are required reading.

Whenever I see a product with a misleading name or label, I harken back to this little snippet from "Shirt", by The Bonzo Dog Band :

This misleading home and garden advertising is referred to as "Greenwashing", the practice of companies disingenuously spinning products and policies as environmentally friendly.

In April 2008  sustainability communications firm Futerra launched The Greenwash Guide. This guide states that Greenwash is an environmental claim which is unsubstantiated (a fib) or irrelevant (a distraction). Found in all forms of marketing and corporate communications, from packaging, PR and advertising claims to CEO speeches and made about people, organisations and products. Greenwash is an old concept, wrapped in a very modern incarnation.

Here are 10 Warning Signs of Greenwashing you might find on a garden product or its advertising:

1. Fluffy language

Words or terms with no clear meaning, e.g. ‘eco-friendly’.

2. Green products vs. dirty company

Such as efficient light bulbs made in a factory which pollutes rivers.

3. Suggestive pictures

Green images that indicate a (un-justified) green impact e.g. flowers blooming from exhaust pipes.

4. Irrelevant claims

Emphasizing one tiny green attribute when everything else is un-green

5. Best in class?

Declaring you are slightly greener than the rest, even if the rest are pretty terrible.

6. Just not credible

‘Eco friendly’ cigarettes anyone? ‘Greening’ a dangerous product doesn’t make it safe.

7. Gobbledygook

Jargon and information that only a scientist could check or understand.

8. Imaginary friends

A ‘label’ that looks like third party endorsement …except it’s made up.

9. No proof

It could be right, but where’s the evidence?

10. Out-right lying

Totally fabricated claims or data.

Greenwashing took an interesting turn a couple of weeks ago locally here in Sacramento, when a newspaper ad by a local nursery took this to a new level. The prominent display in the ad was this.

So, what were the "environmentally gentle" products in the ad?

 All three of the products displayed prominently at the top of the ad would certainly qualify as more environmentally friendly than many of their counterparts, but with reservations (Read the complete label to make sure it is right for you. There may be less toxic alternatives). 

But what about the other products featured in the ad, specifically those with that leaf next to their names? A reader might assume that the leaf refers to a product that is "gentle on our environment and the wildlife that inhabits it." Shame on you for assuming!

Sacramento-area  organic gardening consultant, Steve Zien of Living Resources Company, took exception to some of those leaf-highlighted products:

"Preen Garden Weed Preventer, Sevin Concentrated Bug Killer and Corry’s Slug and Snail Death were included in this classification," says Zien. Let's discuss each product individually and see if we agree with the claim that these are environmentally soft products.

Preen’s pesticide label states, 'This pesticide is extremely toxic to freshwater marine, and estuarine fish and aquatic invertebrates. Causes moderate eye irritation. Harmful if swallowed, inhaled or absorbed through skin. Avoid contact with eyes, skin or clothing.' Trifluralin is the active ingredient (killing agent) in Preen. The US Environmental Protection Agency states, 'No information is available on the acute (short-term), chronic (long-term), reproductive, developmental, or carcinogenic effects of trifluralin in humans.'  The EPA also has classified this pesticide as a possible human carcinogen (cancer causing agent). With that in mind I feel I can safely say Preen is by no means gentle on the environment or those that dwell in it."

"Sevin is even worse, says Zien. "The label states, 'This product is extremely toxic to aquatic and estuarine invertebrates. BEE CAUTION: MAY KILL HONEYBEE IN SUBSTANTIAL NUMBERS.' The US EPA classifies Seven (active ingredient, carbaryl) as “Likely to be carcinogenic in humans.” Extoxnet, (a service of universities) states, 'Carbaryl is moderately to very toxic. It can produce adverse effects in humans by skin contact, inhalation, or ingestion.'"

"Regarding 'Corry’s Slug and Snail Death', the active ingredient is metaldehyde (shortened to 'Meta' in radio and television advertising). The product label states, 'This pesticide may be fatal to dogs or other pets if eaten.' In California it is one of the most common poisoning agents in dogs. Does this sound like a 'green' pest control product to you? It certainly doesn’t to me."

"It is understandable when a big box store provides misleading green washing information because the folks in the advertising department don’t know any better," says Zien. "But one would expect higher standards from a local nursery that is trying to serve our community. Personally, I want to buy my horticultural supplies from manufacturers and local nurseries that do not practice green washing. When choosing a product or where to make my purchase I will choose companies that are making a concerted effort to offer and promote organic horticultural products."

Bottom line for gardeners: Read and follow all label directions. And think about alternatives before applying any pesticides. A good site for that information is the UC Davis Integrated Pest Management Program, which offers cultural, mechanical and physical controls as well as chemical controls for plant problems.