Design trends

Watering the Right Way

Salvia Hot Lips is popular in drought tolerant gardens.

Think like a plant. The weather might be cool one day, really hot the next day. And your plants are growing like mad in order to reproduce which is their s life’s work. All this takes water which is the elixir of life for us and all living organisms. But just how much water do my plants need? I don’t want to overwater and waste this precious resource but neither do I want to lose my botanical friends. Here are some guidelines you might find helpful.

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.

With summer water bills arriving soon 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’re not watering deep enough to moisten the entire root ball or if you’re irrigating too often.

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 above 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.

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 inches of soil is dry. Water large shrubs and trees when the top 6-12 inches 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 inches 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 recommendations. 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 reach 12-24 inches deep in the soil. Established native shrubs may need only monthly watering 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 inches or so and may need watering once or twice a week depending on type and weather.

When is the best time to water? Watering in the morning is the most efficient time whether you water by sprinkler, drip system, soaker hose or by hand because the water soaks deep in the soil without risk of evaporation. This 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. Don’t forget your pots. On a hot day, you can water midday to not only supply moisture but to cool the soil. You would’t want to live in a pot where the temperature at the roots could reach over a hundred either.

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. But no matter the time of day, a plant that needs water should get the right amount. In all the time I worked at a nursery I never saw a plant that was scorched by water on the leaf surface no matter what time of day it was watered.

Dendromecon grow in the Saanta Cruz Mountains with not summer water in the right conditions.

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.

Design trends

Best Flowers for Year-Round Bouquets

Want to be able to walk outside and pick some flowers to take to a friend’s house or bring inside to enjoy yourself? Not long ago I was looking around my own little garden for good flowers to cut for a bouquet. I had some snapdragons, hellebores and lily-of-the valley shrub flowers to cut. Now I’m thinking about what flowers will be blooming soon and what I might plant now to add to my garden.

Besides snapdragons that bloom almost year round and were recognized as ’Cut Flower of the Year” by the Association of…Cut Flower Growers, I have Crocosmia that will be blooming soon. Their arching stems and brightly colored, long-lasting blossoms will look great in a bouquet.

I also have old fashioned Shasta Daisy. Those long sturdy stems hold up well in a vase. Growing also in my little garden are Calla lily, Alstroemeria, Hydrangeas and Roses. Unfortunately my Flowering Maple (abutilon) which the hummers love, have a very short vase life is.

Until about 100 years ago, one of the most important areas of any large garden was the cutting garden where flowers were harvested like a crop and taken inside for display. Today our lifestyles and tastes are reflected in bouquets that are more casual. The bouquets you make from garden grown flowers, interesting foliage branches, grasses, vines and even herbs always seem to have more personality and cottage garden softness than ones bought from the store.

Flowers that lend themselves to cutting, with long stems and a long vase life, can be incorporated into any spot of the garden but if you enjoy lots of cut flowers indoors you may want to sett aside a small bed primarily for an old-fashioned cutting garden. A seldom used side yard would be an ideal place as long as it receives at least a half day of sun. Or how about that narrow bed along the fence you never know what to do with? if you’ve never planted in the soil of your future cutting garden, amend the soil generously with organic matter or compost. Then water to germinate weed seeds and hoe them off. Don’t turn the soil again as you’ll bring up more weed seeds. Now you’re ready to plant.

In shady gardens, fragrant daphne odora is a wonderful small shrub that provides interesting variegated foliage as well as flowers. Sweet olive or osmanthus fragrans blooms smell like apricots. Oakleaf hydrangea foliage and flowers look great in bouquets and the leaves turn red in fall which is an added bonus. Our native shrub philadelphus, also called mock orange, has flowers that smell like oranges and will grow in some shade as well as sun. Pittosporum ‘Marjorie Channon’ will add white with a hint of lime to your bouquets.

For sunny spots grow perennials like penstemon and kangaroo paw. Also coneflowers, dahlias, gloriosa daisy, delphinium, foxglove, scabiosa, aster, shasta daisy and yarrow are good as cut flowers. Coreopsis attract butterflies and are long lasting in bouquets.

Self-sowing annuals that have a long vase life are bachelor buttons, clarkia, cosmos, flax, love-in-a-mist, nasturtium, cleome and calendula. Annual flowers such as zinnia, lisianthus, snapdragon, statice and marigolds are great in containers where you can make every drop of water count and are also good for cutting.

Native flowers that last for a week or more include Clarkia and Sticky Monkeyflower. Yarrow and hummingbird sage will last 4-6 days.

While just about any plant material that strikes your fancy will work in a mixed bouquet there are four types of plant forms that naturally look good together: Spires for height and architectural properties with flowers like liatris, snapdragon, gladiola, salvia, Bells-of-Ireland as well as the strappy leaves of flax or cordyline. Round flowers such as roses, dahlias, long-stemmed marigolds and peonies provide focus. Lacy flowers are fillers- ferns, baby’s breath, dill. Foliage from shrubs such as abelia, breath of heaven, California. bay, ornamental grasses, grapes and other vines, herbs, woody tree branches like smoke tree and Japanese maple which also look handsome in a bouquet.

A deconstructed arrangement separates each type of flower into their own vase or container instead of grouping them in a mixed bouquet. Vary the size and shape of the vases and containers and group them together to create a unique vignette.

Design trends

Best Native Plants for Containers

Penstemon heterophyllus ‘Margarita B.O.P.’

A couple weeks ago I wrote about including California native plants in your garden. Since I have limited ground to garden I mostly have containers and have been quite successful as long as I match the sun or shade to the right plant. You’ve heard it before: “Right Plant, Right Place”
So here are some tips on native plants that do well in containers.

At my front entry that gets morning sun only I have a huge coral bells (Heuchera micrantha) that started out as a cutting wrapped in wet paper towels that a neighbor had found growing at the edge of the forest nearby. It loves it here. Other plants like salvia would not be happy there at all.So it’s definitely the right plant for the right place.I ’ll have to divide and transplant it next spring but it blooms for such a long time and the hummers love it so I never want to disturb it.

Adding California natives to my collection of container plants has been a goal for a long time. Besides attracting birds and wildlife to the garden they use less water than most container plants plus they are beautiful.

Gardening in containers is easy. You can control the soil, water and light and the gophers can’t undermine your efforts. There are a lot of California native plants that do well in containers and I’m going to place them where both the birds and I can enjoy them.

For some of my largest containers I’ll choose from natives like Western Azalea (Rhododendron occidentale), Deer Grass, Chaparral Pea or Giant Chain Fern. Any of the taller growing ceanothus and manzanita would look great too by themselves or combined with smaller growing plants.

Lewisia

For small to medium containers I can use Conejo Buckwheat, Hummingbird Mint, Penstemon heterophyllus, Mimulus, Woolly Blue Curls or Coastal Daisy, These combine well with colorful Lewisia, Dog Violets or Wild Strawberry.

I might combine a madrone with a Canyon Gray Coastal Sagebrush (Artemisia californica) which grows about a foot high and will trail over the side of the container adding beautiful gray color to contrast with the rich green of the other leaves. I also like the combination of California Hazelnut, Deer Fern, Redwood Sorrel and Wild Ginger.

Some of the most dramatic containers utilize the concept of combining a thriller, some fillers and spiller or two. Not all my containers will use this formula but I seem to be drawn to those that do. Plants in nature can be quite random in the way they grow together and still be lovely. Containers need a bit more order to dazzle and direct the eye.

Thrillers act as the centerpiece of a container. They are usually big, bold and beautiful. Giant Elk Clover is one such California native that is an attention getter. Chilopsis linearis (Desert Willow) is another great subject for containers as it is slow growing and beautiful in leaf and flower. Other architectural natives that will catch your eye as the centerpiece of a container are Hardy Hibiscus (Rose Mallow) and Pacific Dogwood. The thriller goes in the center of the pot or if your container will be viewed from only one side it goes in the back.

Next come the fillers. They can be foliage or flowering plants but they should complement and not overwhelm your largest plant. Usually they have a mounding shape and I’ll plant several around the thriller. Good fillers include Heuchera micrantha and Western Maidenhair fern.

The last plants I’ll add are the spillers which are small and will soften the edge of the container. Redwood Sorrel, Wild Ginger and Miner’s Lettuce are good choices. California Fuchsia would look spectacular with its red or orange flowers and grey foliage spilling down the side of my container.

The best overall soil mix for natives in containers is sharp sand and horticultural pumice added to a good potting soil. Never use perlite or that puffed up pumice because it will float and look terrible. Happy Container Gardening.

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