dogwoods, Flowering trees, plant diseases, planting tips, trees

The Best Dogwoods & How to Grow Them

Alluvial_Terrace_wholesale_nursery
Alluvial Terrace Nursery

There?s nothing like learning about trees from someone who has discovered for themselves what makes a winner and how to grow it. Recently I had the opportunity to tour a small wholesale nursery near Corralitos. Jon Craig has evolved from Silicon engineer to a propagator of plants and trees and he?s all the happier for it. He laughs when he says he has loved plants for a very long time starting with his first job mowing lawns. As a former engineer it?s all about the research and the plants he grows showcase his success.

His very favorite tree is the dogwood. Not just any dogwood but the ones that bloom with the largest flowers for the longest time. There are four main species of dogwood trees. From the Himalayas in China comes cornus capitata, Korea is home to cornus kousa. Cornus florida grows on the east coast and the west coast is home to cornus nuttallii or Western dogwood.

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Jon Craig with cornus capitata ‘Mountain Moon’

We are all familiar with the Eastern dogwood that blooms early in the spring. It?s beautiful but rain and wind can cut short the flowering season many a year and the root system is prone to disease. Our Western dogwood is prone to leaf spot fungal diseases. The Kousa dogwood is a more drought tolerant, disease resistant and a tougher plant all around. Large, showy flowers open after the tree has leafed out and remain for a long time. This makes it good for hybridizing with other varieties.

The Stella series is a mix of a florida on kousa dogwood roots. Vesuvius series is a cross of our native nuttallii with a florida as is Eddie?s White Wonder. There is also a nuttullii-kousa cross called Venus that displays huge flowers and gets its disease resistance from the kousa roots. All these cultivars strive to produce a tree with superior disease resistance and huge, long lasting blooms.

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Mountain Moon

Deciduous dogwoods don?t like wet feet especially in the winter. That?s how they develop fungal disease. But there?s an evergreen dogwood that can handle moisture all year round. That tree is Jon Craig?s very favorite. With a name like Mountain Moon you can just picture it blooming high in the Himalayas. Huge flowers up to 6? wide can last from late spring into early summer. After flowering, the fruits begin to form and grow into red balls about the size of large strawberries. This is the reason is it also known as the Himalayan Strawberry Tree. They are edible but bland and tasteless to us. The birds love then though and they remain on the tree while woodpeckers and robins have a feast.

Cornus capitata ‘Mountain Moon’ is a tough tree that can handle strong winds and isn?t bothered by any pests or diseases. They enjoy lots of organic matter as do all dogwoods. Many people think of dogwoods as an understory tree but this location is often too shady. Grow them in a full or partial sun location that gets afternoon shade after 4pm. Add a couple of extra drip emitters or inline drip tubing to your irrigation system and they?re happy.

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Ruby Fall redbud

Besides enjoying the hundreds of blooming dogwoods, I learned about a redbud that is not as fussy as the lovely Forest Pansy. Ruby Falls and Merlot promise to be more reliable in the garden and more heat resistant.

Jon will try his hand growing just about any plant that he thinks others will also enjoy. A fine crop of Alice oakleaf hydrangea grew near a block of Michelia ‘Inspiration’ getting ready to flower and scent the air. The lilacs had finished blooming but the peonies were just starting their show. Jon shared a tip about tree peonies he learned recently from a well-seasoned Japanese gardener. He followed her advice and cut back the tree peony stem in the dormant season forcing it to produce new stems. Voila- they are now loaded with flowers.

peony
peony

Jon grows many other types of dogwood and also Copper beech, magnolia macrophylla, Royal Raindrops crabapple , Sheri?s Cloud nyssa and even a Purple-leaved hazel. I could only fit a couple of 5 gallon cans in my car so a beautiful smoke bush in full bloom and a Black Lace elderberry now call Bonny Doon home. But I have my eye on one of those spectacular Mountain Moon evergreen dogwoods for the back garden.

birds, butterfly plants, California drought, California Native Plants, drought tolerant gardens, drought tolerant plants, irrigation, watering

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.

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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.

euphorbia sap, gardening tips, organic mulch, poison oak, ramial bark chips, toxic sap

Keeping Gardening Facts Straight

I?ve gotten several emails lately requesting more information about something mentioned in a recent column. I also received a phone call from a reader describing a bad encounter with a certain common plant. She wanted to share her experience so it didn?t wouldn?t happen to anybody else. And a conversation about how bad the poison oak is this year triggered a discussion about how to dispose of the stuff. So here goes. All the news that?s fit to print.

Whether it was Joe Friday who said it or Dan Akroyd in the Dragnet parody. we all want ?Just the Facts, Ma?am?.

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ramial bark chips

In my column a couple weeks ago about garden planning for the drought, it was the last line ?And don?t forget the? mulch (no shredded bark, please)? that caused a bit of confusion. It?s great that everyone has accepted the value of covering the soil with organic mulch. Organic mulches- such as bark chips, treated sawdust, straw or even grass clippings- keep plant roots cool, encourage earthworms and other beneficial organisms, conserve soil moisture, combat weed growth and protect the soil from erosion.

But is there an organic mulch that is better than another?

There are many types of mulch available. Nurseries sell different types of mulch in bags, building supply yards carry everything from bark nuggets in different sizes to treated sawdust to chipped bark and even shredded redwood bark. It?s the shredded redwood bark, also called gorilla hair, that does nothing for the health of your soil. If you have a very steep slope you may have to go with this type of mulch but that?s the only time I can recommend it. It will cling to a hillside without washing down in winter rains but treated sawdust would also work for this type of terrain and is much better for soil health.

Of all the types of organic mulches out there, recent studies have shown that ramial bark chips are one of the best mulches to improve soil health. Ramial chips come from trees and brush with branches up to about 3? in diameter with or without leaves. These chips contain a high percentage of thin young bark and young wood. This is what makes them so valuable to the garden. Young wood is a tree?s factory for producing protein, glucose, fructose, lignin and polysaccharides. It’s an important source of nutrients for living things at all levels according to a study by soil scientists, G.Lemieux and R.A.Lapointe. You can obtain these kind of chips free from tree trimming companies who are probably working nearby chipping roadside brush for PG&E.

euphorbia2
Euphorbia

About that call from a reader who had a terrible experience after pulling some plants in her yard that had gotten a little out of hand. She said she and her husband ended up with severe eye burn after getting some toxic sap from euphorbia in them. She said they really don?t know if some of sap became airborne while they were pulling stems or if they accidentally rubbed some near their eyes at some point in the day. They went to Urgent Care right away for treatment but the pain lasted for days. She described it as one of the most painful experiences she has ever had. Euphorbias are very deer resistant and drought tolerant and are being used more and more in gardens.

Many of us, me included, grow tropical milkweed or Asclepias curassavica to attract monarch butterflies. The milky sap from this plant protects the monarch from being eaten and can cause the same painful burning of the eye. I read of a case where a gardener?s clothes brushed some stems while she was tending the garden. Later she wiped the sweat out of her eyes and didn?t realize she had also touched her pants. She ended up with cornea burn causing temporary blindness and had to take strong pain relievers and steroids to elevate the pain.

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Poison oak

Lastly, a fine crop of poison oak is growing this year so thick in places you can barely avoid it. The new foliage literally glistens with toxic oils. Many birds relish the white berries that form later in the season. 9 out of 10 people will get a rash if even one drop of urushiol oil touches the skin. And this oil has lasting power. It can stay active on any surface, including dead plants, for up to 5 years. Burning dead or dormant poison oak branches is especially dangerous as urushiol oils released in smoke can produce disastrous results if inhaled. So what to do with the stuff if you pull it out? Do not put it in your green waste can. It can end up being ground into mulch along with other green waste. Instead put it in your gray garbage can. Other plant matter that has to be put in the garbage can is pampas grass and bamboo. Don?t put them into green waste

So that?s the skinny on shredded redwood or gorilla hair, common plants with toxic sap and poison oak disposal. Be careful out there.

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