Design trends

Making your Garden more Sustainable

You know you have a sustainable landscape when the tree frogs come to visit.

Summers are getting hotter and hotter. Our winters are colder. Climate change is affecting our gardens, too. You might be on the right track of sustainability and stewardship of the environment but can you do more?
How can we live more in harmony with nature? Here are some tips to make it more sustainable.

Incorporate as many California native plants as you can. It really does help. Encourage bees and other pollinators by creating a sustainable habitat for them in your garden. Water wisely to conserve our finite water supply. Use organic pest control only if necessary to protect our watersheds from chemical contamination.

How can I sequester more carbon by my plants to store in the soil? How can I protect the biodiversity already in place in my mixed redwood forest environment? Even though I don’t have the right conditions to grow my own organic food I can buy from growers who use ecological process on their farms. What native plants around my own house can I eat? Miner’s lettuce comes to mind but you probably have many more growing in your garden.

You hear the word sustainability used to describe everything from flooring to roofing to landscaping but what exactly is a sustainable landscape?

Sustainable landscapes are so well adapted to their environment that they require little in maintenance. Choosing plants adapted to your garden size, type of soil and climate keeps watering and fertilizing to a sensible level and reduces pruning as plants grow to the size needed and stay there.

Sustainable landscapes use recycled, salvaged, durable building materials whenever possible. They use mainly materials that are harvested locally and use imported stone as an accent. Sustainable landscapes try to reuse what you already have laying it out differently to look like a totally new landscape.

Sustainable landscapes clean the air and water. They increase on-site infiltration of rain water to reduce runoff and minimize the amount of contaminants washed into the watershed and the bay. By keeping water onsite it can move into the soil where organisms breakdown pollutants and naturally filter them out before the water reaches groundwater or our waterways.

Sustainable landscapes conserve water by installing and maintaining high efficiency watering systems making every drop of irrigation water count. They create drought resistant soils by adding compost and mulch. They group plants by watering needs to irrigate them more efficiently.

Banana slug

Sustainable landscapes restore habitats by attracting native pollinators, beneficial insects and other organisms that reduce the need for pesticides. A sustainable landscape restores natural areas on the outskirts of your landscape to diversity the plant community.

Embrace the smaller garden. You can create an instant meditation garden that encourages you to stop and sit for a couple minutes by placing a small bench where you can view something interesting in your garden. Small gardens are not only compact they are easier to care for. Containers on the patio or deck allow you to grow plants for food as well as for the birds and the bees. There are more new dwarf vegetable, herb and flower varieties being introduced every year.

Combine ornamental plants with edibles. Your veggies don’t have to be in a special raised bed or plot but can be planted throughout the garden. Think tomatoes, pole beans and other vining veggies trained on a metal obelisk within a perennial bed. Or compact versions of beans, eggplant, chard, hot peppers, tomatoes or edible flowers like nasturtiums planted among your other plants or along path borders.

Sustainable landscapes are responsive to the environment, re-generative, energy efficient and can actively contribute to the development of healthy communities.

Design trends

Screen the Neighbors with Low Water Use Plants

Loropetalum can screen unsightly views.

We all enjoy privacy around our homes. Even if you’re best friends with your neighbor you don’t always want to wave at them each morning. Whether you have a property tucked way back in the forest with a next door neighbor that looks right down on your deck or a postage stamp size lot that could be a jewel if you just had a screen between you and the next property, there are techniques designers use to make your home a private oasis.

Many people only think of plants that remain evergreen when they need screening. However, if you use one-third deciduous plants to two-thirds broadleaf evergreens they will weave together and you won’t be able to tell where one leaves off and another begins. This makes mature hedges secure borders, especially if you throw a few barberries or other prickly plant into the mix. You’ll also get seasonal interest with fall color and berries for wildlife.

Narrow spaces can be challenging when you need to screen the house next door. If there’s not room for a big, evergreen tree or hedge to solve the problem. One way is to use plants that can be espaliered against a fence or trellis. Some plants like azara microphylla naturally grow flat without much coaxing on your part. This small dainty tree is fast growing and reaches 15-25 ft tall. The yellow flower clusters will fill your garden with the scent of white chocolate in late winter. They are ideal between structures. I’ve used the variegated version to screen a shower and it’s working great.

Another small tree, the Compact Carolina cherry laurel can be espaliered also in a narrow space if needed. It grows 10 ft tall but that may be all you need to screen the neighbor. They are drought tolerant once established, deer resistant and the perfect host for birds, bees and butterflies. The leaves smell like cherries when crushed which gives this plant its common name.

Other small trees that make a good screen are purple hopseed, and leptospermum ‘Dark Shadows’. Both have beautiful burgundy foliage. California natives that can be espaliered against a fence include Santa Cruz Island ironwood, Western redbud, mountain mahogany, toyon, pink flowering currant, Oregon grape and spicebush.

Prostanthera Variegata

Variegated Mint Bush (Prostanthera ovalifolia ‘Variegata’) is another shrub to consider for a living hedge. Creating pleasing plant combinations is a big part of gardening and this one would look great alongside a Fringe Flower of either color. Allow each plant to interweave and grow together. The Mint Bush will grow 4-6 feet tall and 3-5 feet high. The foliage smells very strongly like mint so deer avoid this shrub, too.

Myrica californica

If you have a wider space to grow screening plants, one of my favorites is Pacific wax myrtle. This California native grows quickly to 30 ft tall with glossy, rich forest green leaves. Its dense branches make a nice visual and noise screen for just about anything or anybody. I’ve never used the subtle spicy leaves for flavoring sauces but I might try it next time a recipe calls for bay leaves. Best of all the fragrant waxy purplish brown fruits attract many kinds of birds.

Italian buckthorn is another evergreen screening shrub to consider. It reaches about 15 feet tall by 6-8 ft wide and has low water needs. It can grow 2-3 feet in its first few years making a quick screen. There’s a variegated version with stunning foliage that looks awesome mixed with the green variety in a hedge.

Choisya

Another favorite hedge plant, the California coffeeberry grows 6-8 feet tall and gets by with very little summer water once established. Birds love the berries.
I also like osmanthus fragrans and choisya for a screen both with a sweet scent and pittosporum ‘Marjorie Channon’ or ‘Silver Sheen’ with their showy variegated foliage.

To keep down maintenance, mulch around your plants and install drip irrigation. There won’t be any pruning to do if you choose plants that grow to the height you want. Mixed hedges appeal to bees, butterflies and songbirds while also providing flowers, berries and color throughout the year for you to enjoy.

How close should you plant a mixed hedge? Depending on the mature size of the plant spacing could be from 3-5 feet part If you want a quick, thick screen.This gives them room to breathe and develop their own shapes. Fast growing plants can be space 5-6 feet apart or more and will usually full in within 5 years.

Provide the best growing environment for the fastest results. By this I mean amending the soil at planting time if your soil is not very fertile. Cover the soil with mulch and fertilize with compost or organic fertilizer. Watering deeply when needed especially during the first three years after planting when young plants put on a lot of growth. Formal hedges are fine for some gardens but think of all the added benefits you’ll get planting a mixed hedge.

If it’s just not practical to screen the perimeter of your property redirect your line of sight to keep attention focused on the garden instead of on the landscape beyond. A recirculating fountain as simple as an urn spilling onto cobbles at the base can disguise noise and become the focal point. There are lots of ways to add privacy to your home.

Design trends

Watering: Making Every Drop Count

Fremontodendron – a low water use Ca. native

File this under the heading “Be careful what you wish for.” The Dog Days of Summer aren’t even here yet but the thermometer is inching toward 100 degrees. How’s your garden looking?

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?

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.

Mimulus aurantiacus

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.

California fuchsia

Other well adapted plants that are known to be more tolerant of heat include leucadendron, 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 inches is dry, 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 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 inches deep and require 10 gallons of water per inch of trunk diameter.

Safari Sunset leaucadendron

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 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.

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

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