Category Archives: watering

Make Every Drop Count:Best Watering Practices

Low water-use leucospermum or Pincushion.

Water is our most precious resource. One of the Apollo 11 astronauts recently said that the look back from the moon at our planet and blue oceans to be even more impressive than the moon itself. Life can’t exist without water. You are the steward of your own piece of planet earth. How you water can make it thrive and you can save water at the same time.

With summer water bills arriving this is a good time to re-visit how often and how much to water that landscape you’ve spent so much money to create. Basically, you’re wasting water if you water too shallow or too often. Here are some guidelines.

Photosynthesis is one of the most remarkable biochemical processes on earth and allows plants to use sunlight to make food from water and carbon dioxide. At temperatures about 104 degrees, however, the enzymes that carry out photosynthesis lose their shape and functionality. A garden that provides optimum light and water but gets too hot will be less vigorous.

California native Fremontodendron

Plants have natural systems that respond to heat problems. Plants can cool themselves by pumping water out through the leaves for a kind of swamp cooler effect. They can also make “heat-shock” proteins which reduces problems from over heating. All these strategies can take resources away from a plant’s other needs like growth, flowering and fruiting.

So how much water do different types of plants need during the heat of summer?

Be sure that you water trees and shrubs deeply checking soil moisture first with a trowel. Established small to medium shrubs should be watered when the top 3-6″ is dry, large shrubs and trees when the top 6-12″ is dry.

As a rule of thumb, trees and large shrubs need deep but infrequent watering. They should be on a separate valve than your smaller shrubs and perennials. Water ornamental trees 1-3 times per month depending on the type and soil. Tree roots grow 12-36” deep and require 10 gallons of water per inch of trunk diameter.

Apply water with a soaker hose, drip system emitters or hand held hose with shut off and soft spray attachment according to your water district’s restrictions. Don’t dig holes in the ground in an effort to water deeply. This dries out roots even more. Be sure to water the root zone to the indicated root depth every time you water. Watering deeper than the root zone only means you are wasting water. You can test how deep you watered by pushing a thin, smooth rod into the ground soon after you irrigate. The soil probe should easily slide through the wet soil but become difficult to push when reaching dry soil.

The roots of smaller shrubs are 12-24” deep in the soil. Established native shrubs may need only monthly waterings to keep them looking their best while other shrubs may need watering every 7-10 days during the heat of the summer. Perennial roots only go down 12” or so and may need watering once or twice a week depending on type.

grevillea lanigera ‘Mt. Tamboritha’ groundcover

When is the best time to water? Watering in the morning is the most efficient whether you water by sprinkler, drip system, soaker hose or by hand. The water soaks deep in the soil without risk of evaporation. It bolsters the plant for the day and has dried from leaves by evening reducing the risk for foliar diseases like mildew. Plant roots are also more receptive to watering in the morning.

Is it true that water droplets will scorch leaves in the midday sun? According to a study, fuzzy-leaved plants hold water droplets above the leaf surface and act as a magnifying glass to the light beaming through them so there is a very slight chance of scorch. The study also reported that water droplets on smooth leaves, such as maples, cannot cause leaf burn, regardless of the time of day.

Watering Plants in the Summertime

All plants need water– even those that are tolerant of our summer dry conditions. Water makes up 90-98% of every plant we grow. It’s needed for photosynthesis, as well as reproduction and defense against pests.

What happens to a plant when the thermometer tops 100 degrees? Are there some plants that can survive tough times more easily?

Mimulus ‘Jelly Bean Gold’

Photosynthesis is one of the most remarkable biochemical processes on earth and allows plants to use sunlight to make food from water and carbon dioxide. At temperatures about 104 degrees, however, the enzymes that carry out photosynthesis lose their shape and functionality. A garden that provides optimum light and water but gets too hot will be less vigorous. Tomatoes, for example, will drop blossoms and not set fruit if temperatures are over 90 degrees. Plants that do endure hight heat may be stunted and weakened attracting pests and diseases even if water is available.

Plants have natural systems that respond to heat problems. Plants can cool themselves by pumping water out through the leaves for a kind of swamp cooler effect. They can also make “heat-shock” proteins which reduces problems from over heating. All these strategies can take resources away from a plants other needs like growth, flowering and fruiting.

California fuchsia

It’s no surprise that many California natives are adapted to high temperatures. Some California native plants that can handle the heat with little water include salvia, mimulus, California fuchsia, eriogonum, manzanita, artemisia, California milkweed, ceanothus, mountain mahogany, bush poppy, bush lupine, native penstemon, monardella, mahonia nevinii, fremontodendron and holly-leafed cherry.

Other well adapted plants that are known to be more tolerant of heat include butterfly bush, germander, rosemary, smoke tree, rudbeckia, coreopsis, lantana, plumbago, gaillardia, lilac, sedums, oregano and verbena.

So how much water do different types of plants need during the heat of summer?

Be sure that you water trees and shrubs deeply checking soil moisture first with a trowel. Established small to medium shrubs should be watered when the top 3-6″ is dry, large shrubs and trees when the top 6-12″ is dry.

As a rule of thumb, trees and large shrubs need deep but infrequent irrigation. They should be on a separate valve than your smaller shrubs and perennials. Water ornamental trees 1-3 times per month depending on the type and soil. Tree roots grow 12-36” deep and require 10 gallons of water per inch of trunk diameter.

Bush Poppy

Apply water with a soaker hose, drip system emitters or hand held hose with shut off and soft spray attachment according to your water district’s restrictions. Don’t dig holes in the ground in an effort to water deeply. This dries out roots even more. Be sure to water the root zone to the indicated root depth every time you water. Watering deeper than the root zone only means you are wasting water. You can test how deep you watered by pushing a smooth rod that’s 1/4 inch – 3/8 inch in diameter into the ground soon after you irrigate. The soil probe should easily slide through the wet soil but become difficult to push when reaching dry soil.

The roots of smaller shrubs are 12-24” deep in the soil. Established native shrubs may need only monthly waterings to keep them looking their best while other shrubs may need watering every 7-10 days during the heat of the summer. Perennial roots only go down 12” or so and may need watering once or twice a week depending on type.

With lots of mulch and the above watering tips you can keep all your plants happy and healthy

What Makes for a Sustainable Garden?

The redbud are just starting to show color in my yard. Flowering plum, tulip magnolia, manzanita, forsythia, flowering currant and quince are blooming in many a garden. Even the deciduous trees and plants that look bare now are starting to grow new roots deep underground. It’s time to plan this year’s garden. Think about how you can blend artistry with ecology.

Garden to attract birds, bees, butterflies and other beneficial insects

A landscape developed with sustainable practices will improve the environment by conserving resources. It will require less maintenance and fertilizing, be balanced with our climate in mind and use less pesticides and water. Most of all it will be visually pleasing with lots of flowers. bees and butterflies.

Your goal may be a more drought tolerant garden but which plants are right for your yard? What plants will be more likely to withstand disease and pest damage? What kind of irrigation system should be installed to provide for the needs of the landscape in the most efficient way possible? Is it time to convert your sprinkler system to smart drip, inline drip emitters and micro-irrigation?

Where do you put the compost bin so you can return garden waste and kitchen waste back to the garden while recycling nutrients within the landscape? How do you keep the soil healthy? There are many components in designing and installing a sustainable landscape that is just right for your garden.

Start with a smart design. Utilize permeable paving like gravel or pavers to help manage runoff, giving the soil more time to absorb rainfall and recharge the ground water. Maybe you need a rain garden or small planted basin to catch and filter rainwater and keep it onsite.

Planting bed of plants with similar watering needs.

Group plants in your garden according to their water needs. Now’s the time to transplant if necessary to achieve this. Some maybe can survive on rainfall alone after their second or third season while the perennial beds and vegetable garden will require a different schedule. Water slowly, deeply and infrequently so there is no runoff. Water in early morning or evening to maximize absorption.

Plant deciduous trees to provide cooling shade in the summer and allow sunlight to warm the house in winter. Trees and shrubs clean the air of nitrogen, sulfur dioxide, ozone and carbon monoxide. They breathe in carbon dioxide, a major greenhouse gas, use the carbon to grow, then exhale oxygen. They retain more carbon than they lose so every tree you plant helps reduce your carbon footprint on the planet.

Feed and shelter birds, butterflies and other wildlife in your landscape. Plant perennials such as echinacea, lavender, penstemon or salvia, ceanothus and other native plants to attract pollinators like bees and hummingbirds. Plant flowers that attract beneficial insects to help control harmful insects and use organic pesticides.

Make your soil a priority by adding compost each year. Mulch your soil to keep down weeds and conserve water and use organic fertilizers, manure and fish emulsion that feed the soil. Compost the green and brown waste your garden produces like fallen leaves, weeds without seeds, grass clippings, spent flowers and vegetables.
Stay ahead of weeds, pulling them before they set seed and spread.

Take steps each year to encourage a beautiful, sustainable landscape and make your corner of the world part of the solution.

Watering Tips when Planting for the Birds & Bees

Western Tiger Swallowtail butterfly

I may not be so fond of gophers but I never tire of the birds, butterflies and bees that visit my garden. I’m always on the look out for plants that will attract even more of these exquisite creatures and it’s one of the top requests for nearly every garden that I design. Fortunately there are many plants that fit the bill and have low water requirements for our summer dry climate.

Trees that provide fruit, seeds, nectar and protein from insects attract many kinds of songbirds. Our native Big Leaf Maple is a favorite of the Evening Grosbeak who relish the seeds and early spring buds. Another bird magnet is the dogwood. Our Pacific dogwood as well as the Eastern dogwood and even the hybrid of the two, Eddie’s White Wonder, all are very valuable sources of food for many birds. Their summer berries are high in fat and important for migratory and wintering birds.

Lesser goldfinch

There are many great low water-use shrubs and perennials that attract birds. My favorite Lesser Goldfinch is partial to the seeds of yarrow, buckwheat and aster. Kevin’s mahonia is favored by Western bluebirds. Blooming now in our own neck of the woods is Mexican elderberry. Their butter yellow flowers will form purple berries rich in carbohydrates and protein and attract an incredible number of birds. And I always can find space for another variety of manzanita or ceanothus.

Mimulus ‘Jelly Bean Gold’

Both hummingbirds and butterflies are attracted to flowers that provide nectar. Among their favorites that won’t break your water budget are natives such as penstemon and salvia. galvezia, mimulus, monardella. California fuchsia and ribes are also important nectar sources for birds in your garden. Add a couple non-native, drought tolerant perennials like lavender, gaura, coreopsis, verbena, scabiosa, lantana and wallflower and you’ll provide a feast for all your winged visitors.

So how much water do different types of plants need during the heat of summer?

As a rule of thumb, trees and large shrubs need deep but infrequent waterings. They should be on a separate valve than your smaller shrubs and perennials. Water ornamental trees 1-3 times per month depending on the type and soil. Tree roots grow 12-36” deep and require 10 gallons of water per inch of trunk diameter.

Sambucus nigra berries

Apply with a soaker hose, drip system emitters or hand held hose with shut off and soft spray attachment according to your water districts restrictions. Don’t dig holes in the ground in an effort to water deeply. This dries out roots even more. Be sure to water the root zone to the indicated root depth every time you water. Watering deeper than the root zone only means you are wasting water. You can test how deep you watered by pushing a smooth rod -1/4” – 3/8” in diameter- into the ground soon after you irrigate. The soil probe should easily slide through the wet soil but become difficult to push when reaching dry soil.

The roots of smaller shrubs are 12-24” deep in the soil. Established native shrubs may need only monthly irrigation to keep them looking their best while other shrubs may need watering every 7-10 days during the heat of the summer. Perennial roots only go down 12” or so and may need watering once or twice a week depending on type.

With lots of mulch and the above watering tips you can keep all your plants happy and healthy for the birds, butterflies and bees to enjoy.

Save Water – Save Trees

I had to do it. I couldn’t resist. Even though I’d vowed not to get any new plants until fall planting season when I saw the one gallon Pride of Madeira just begging for a new home I succumbed to my impulse. I rationalized this plant was on my wish list and will be drought tolerant so I wasn’t being totally irresponsible.

I’ve always wanted an echium fastuosum on my hillside. I admire those huge spires of purple-blue flowers whenever I see them in other gardens. These are tough plants getting by with no summer water once established and the flower spikes are bee magnets. I covered it with a layer of shade cloth for a few days because it was so hot when I planted it. This will help it establish more quickly while the roots take hold in the soil.

Flame_tree
Flame tree on Stanford campus

In your own garden it’s wise to establish a drought to-do list. I’m talking about what plants get your precious water and what to let go.

As we enter another dry year many of our ornamental and fruit trees are dying. Many were watered along with the lawn you have now let go brown. Others might have been surviving on natural rainfall. Whatever the case in your garden don’t let your trees die.

Nature has already killed an estimated 12 million trees in Calif. forests since the drought began four years ago. Most of these have fallen victim to bark beetles that attack trees weakened by drought.

In our own neighborhoods, trees are a long-lived asset. A tree is not something that can be easily replaced. It’s OK to appropriately water trees. Dying trees can be a safety hazard and removing a dead tree is expensive.

It takes years to grow a tree to mature size. Save and use shower and cooking water to help them out. Maybe it’s time to install an simple laundry-to-landscape system to water your landscape trees. Or set up a separate drip or soaker hose for your trees and give them a good deep drink at least once or twice a month. And remember that the tree’s feeder roots are not at the base of the trunk but out at the drip line and a little beyond.

laurel tree.1600
Laurel tree on Stanford campus

A rule of thumb for determining when to irrigate is when 50% of the water has been depleted from the soil in the plants’ root zone. This allows a buffer of water in the soil in case the weather suddenly turns hot and windy and applies to trees, shrubs and perennials.

Sandy soils hold less water than clay soils and must be irrigated more frequently. A common misconception is that it takes more water to grow plants in sandy soil than in clay soil. Actually the total amount required for the whole year is the same for both soil types. The amount of sunlight, wind, temperature and humidity control how much water a plants needs – the soil is only the reservoir.

To check the water content in the soil dig 8-16 inches down into the soil with a trowel, shovel or soil tube and feel the soil. At about 50% available water:
* Course soil appears almost dry and forms a ball that does not hold shape.
* Loamy soil forms a dark ball that is somewhat moldable and can form a weak ribbon when squeezed
between the finders.
* Clayey soil forms a good, dark ball and makes a ribbon an inch or so long and slightly sticky.

If you are planning to plant some new trees this fall, be sure they are drought tolerant natives or low water use non-natives. There are many nice specimens to choose from. And don’t skimp on the mulch.

It’s important to maintain our existing tree canopy and plant for the future. Even in times of drought, no especially in drought, planting and stewardship of trees is critical. Not just for their future but for ours as well.

Planting for Birds and Watering Tips

Purple-finch
Purple finch

My garden is alive with birds. Butterflies and bees also seem to find it an interesting place to visit. I’m always on the look out for plants that will attract even more of these exquisite creatures. Fortunately there are many that have low water requirements which is a prerequisite these days.

But how do you plant something new given the new water restrictions? And what about those existing trees, shrubs and perennials that birds, bees and butterflies depend on? How much water do they need to survive?

Everybody loves winged creatures in the garden. Adding plants that attract birds, bees and butterflies is at the top of the list of requests for nearly every garden that I design.

Trees that provide fruit, seeds, nectar and protein from insects attract many kinds of songbirds. Our native Big Leaf Maple is a favorite of the Evening Grosbeak who relish the seeds and early spring buds. Another bird magnet is the dogwood. Our Pacific dogwood as well as the Eastern dogwood and even the hybrid of the two, Eddie’s White Wonder, all are very valuable sources of food for many birds. Their summer berries are high in fat and important for migratory and wintering birds.

achillea_yellow
Achillea

In every garden possible I try to include low water use shrubs and perennials that attract birds. My favorite Lesser Goldfinch is partial to the seeds of yarrow, buckwheat and aster. Kevin’s mahonia is favored by Western bluebirds. Blooming now in our own neck of the woods is Mexican elderberry. Their butter yellow flowers will form purple berries rich in carbohydrates and protein and attract an incredible number of birds. And I always can find space for another variety of manzanita or ceanothus.

Both hummingbirds and butterflies are attracted to flowers that provide nectar. Among their favorites that won’t break your water budget are natives such as penstemon and salvia. Galvezia, mimulus, monardella, California fuchsia and ribes are also important nectar sources for them in your garden. Add a couple non-native, drought tolerant perennials like lavender, gaura, coreopsis, verbena, scabiosa, lantana and wallflower and you’ll provide a feast for all your winged visitors.

So how much water do different types of plants need during the heat of summer?

As a rule of thumb, trees and large shrubs need deep but infrequent waterings. They should be on a separate valve than your smaller shrubs and perennials. After the last two winters of little rain, many trees are showing signs of stress. It’s not easy to replace a tree that will take 20 years to regrow if you have to replant. Water ornamental trees 1-3 times per month depending on the type and soil. Tree roots are 12-36” deep and require 10 gallons of water per inch of trunk diameter.

Apply with a soaker hose, drip system emitters or hand held hose with shut off and soft spray attachment according to your water districts restrictions. Don’t dig holes in the ground in an effort to water deeply. This dries out roots even more. Be sure to water the root zone to the indicated root depth every time you water. Watering deeper than the root zone only means you are wasting water. You can test how deep you watered by pushing a smooth rod -1/4” – 3/8” in diameter- into the ground soon after you irrigate. The soil probe should easily slide through the wet soil but become difficult to push when reaching dry soil.

verbena_Homestead-purple
Homestead Purple verbena

The roots of smaller shrubs are 12-24” deep in the soil. Established native shrubs may need only monthly waterings to keep them looking their best while other shrubs may need watering every 7-10 days during the heat of the summer. Perennial roots only go down 12” or so and may need watering once or twice a week depending on it’s water needs.

With lots of mulch and the above watering tips you can keep all your plants happy and healthy for everyone to enjoy.