Design trends

Finding Our Horticultural Heritage

Planted in the early 1900’s by settlers, canna lilies are easy to care for.

I used to live in Bonny Doon where a huge Tasmanian Tree Fern grew without care on the “lower forty”. It was over 50 years old at the time of the fire having been planted by the original builder of the house. I guess it qualified as a heritage plant. There is so much horticultural history in our area. I’m fascinated by it all.

This area is rich in history. I love to look at old photos and try to identify what the early settlers planted around their homes in the Santa Cruz mountains.

I’ve spent hours reading through the history of the Alba Schoolhouse online. Besides the history of the actual schoolhouse, which dates back to 1895, there are many first person accounts of who grew what crops and how the land along Alba Road was used and is part of our local horticultural history.

Did you know that vineyards stretched along the west side of Empire Grade opposite the eventual route of Alba Road? In 1884, as many as 2000 gallons of wine was produced? The Burns family also had cattle on their ranch. A 1915 photo of their house show palms and hollyhocks, too. Ben Lomond became known for fruit other than grapes. Orchards of prize winning apples, peaches and plums were planted as well as strawberry plants. These crops thrived in the sunshine created by the clear cutting of timber.

Out on Bear Creek Road, the Ercoli villa featured yucca which I saw in many early photographs. Most likely they originated from the deserts in the southern California and Mexico and were brought north by the missionaries.

California fan palms and canna lilies appear in many early landscapes. The Middleton house in Boulder Creek was heavily planted with native western sword ferns. Black locust trees planted for their fragrance and flowers are still seen here today where they have naturalized. Originally planted for erosion control, particularly on strip mined areas, their durable timber was used for homes.

Many settlers arrived from the east coast, the midwest and Europe and brought with them seeds and starts of plants. As early as 1871, nurseries in San Francisco were importing plants such as pittosporum tenuifolium and the 1915 Panama Pacific Exposition in San Francisco allowed many more plants to become available to homeowners. Hebe from New Zealand was all the rage. The brochure for this World Fair describes a Palace of Horticulture and Tower of Jewels as …” a great garden, itself, a marvel of landscape engineering skill… one side of a magic carpet on which these beautiful palaces are set with its floricultural splendors for a wondrous beauty, has never been equaled.”

The 1915 Panama Pacific Expo introduced more than plants to the public. In 1916, construction of a home in Brookdale featured timber, flooring and doors shipped from the Expo to this area by Southern Pacific railroad. When the house was finished in 1926, photographs show a beautiful home surrounded by hollyhocks, roses and wisteria.

My interest in early local horticulture started after looking at a friend’s family photographs from the early 1900’s. His family had a resort with a natural spring and rock-lined forest paths close to Highway 9 in South Felton. This was very near the Big Tree Grove resort ( now Toll House ) that opened in 1867. I remember looking at the photos and marveling at all the flowers surrounding the dwelling. The redwood trees have now grown back but at that time there was lots of sunshine, a by-product of clear cutting. I could see roses, lilacs and Shasta daisies in the photo surrounding a wrap around porch.

Beginning in the 1930’s, peat moss was removed from Scotts Valley and taken to San Francisco to supply soil and fertilizer for difficult indoor plants such as gardenias. The land from Burger King on Scotts Valley Drive over to Safeway on Mt Hermon Road was a peat bog. When the peat ran out, sand and gravel were quarried and sold. There were apple and cherry orchards at the north end of town and vineyards on both sides of Highway 17. The subdivision, The Vineyard, was named to memorialize the past land use.

You can tell a lot about landscape plants from old photographs. It’s a fun trip down memory lane and part of our horticultural heritage. You might even plant a historical garden for the fun of it.

Design trends

Fourth of July in the Garden

A local black-tailed deer celebrating Fourth of July

I don’t grow corn in my small, shady garden so I’m not sure how tall they’d be if by now if I planted on May Day when the soil was 50 degrees, but that’s how the saying goes. This column isn’t about growing corn, however, it’s about climate smart plants that hold up to the heat. So let’s get started.

All this talk about “drought tolerant” plants or “water smart” plants is misleading in some ways. What really matters for the success of a plant in your garden is that they are climate smart. You can call the new California garden climate tolerant or climate adapted but it all comes down to the same thing. The plants you choose to grow in your garden should be able to naturally tolerate periods of lower than average water. This doesn’t mean no water during extremely long dry periods. No plant can live without water.

All of us live in a summer-dry climate. Summer-dry gardens are naturally dry for long periods. Knowing which type of plant community you live in can make the difference between success and failure in your garden. Choose the right plant for the right place whether it’s a California native from an area with similar soil and exposure or a plant from another Mediterranean-like climate with growing conditions like yours.

Plant communities have evolved over time with geologic changes in climate, topography and soils. We have several district areas here- mixed evergreen forest, redwood forest, chaparral and sandhills.

If you live in a mixed evergreen forest you garden with trees like coast live oak, tan oak, madrone, bay and buckeye. Understory plants include ceanothus, coffeeberry, hazel and poison oak. Your soil contains serpentine and granite. Many other unthirsty plants like salvias, lavender, santolina, society garlic, giant feather grass, rosemary and rockrose do well here. California natives such as western mock orange (philadelphus lewisii), wild ginger and western sword ferns grow here also.

Mixed evergreen forest may also be found along canyon bottoms near streams where big leaf maple, white alder, cottonwood, and western sycamore trees grow. Most plant here grow lush in this deep soil. If you are looking to add something new to your garden here consider giant chain fern, aquilegia, dicentra, Pacific Coast iris and fuchsia-flowering gooseberry.

Chaparral areas are the hottest, driest slopes of these mountains. Dense thickets of manzanita, coyote brush, chamise, coffeeberry, ceanothus, monkey flower and sage are native here. These plants are adapted to little water and often have tiny, thick, waxy, light green or grayish leaves. Soils tend to be rocky and shallow with overlaying rock or a subsoil that is mostly clay. Plants here need to have an extensive root system that reaches widely and deeply for water. If you live here a classic combination would be the spring blooming western redbud and Julia Phelps or Dark Star ceanothus. The combination of magenta and electric blue flowers is unforgettable.

The sandhills near Quail Hollow and Bonny Doon around Martin Rd. are part of an ancient sandy sea floor that was uplifted, eroded and exposed. These sandy soils lack organic matter and nutrients and their white color magnifies the temperature of the summer sun. Unique, native plants like silverleaf manzanita and Ben Lomond wallflower live here. Buckwheat and sticky monkey flower do well here. You might also try growing Siskiyou Lewisia, a pretty little plant native to northern California, thrives in sand and gravel soils with good drainage. This 8″ tall hardy perennial blooms from spring to early summer with extremely showy flower clusters in colors ranging from apricot to pink, rose and bright cherry red. Mulch them with gravel or crushed stone.

Remember: right plant-right place. Don’t try to force nature although most gardens do look better with some summer water. Closer to the house we expect a fuller look. Combinations I’m going to try this season include leucospermum paired with blue echium or grey-leafed westringia planted with red-flowering callistemon ‘Little John’.

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.

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.

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