Designing a Shade Garden

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“I can’t grow anything in the shade” is a common lament that I hear all the time. Nothing could be farther from the truth! A shade garden can be colorful all season long, absolutely beautiful, exciting, fragrant, and soothing to the eye. You just have to learn some basic design concepts before you begin….

 

1. Defining the Different Degrees of Shade

You must know how much shade you have before you begin. Examine the site during the course of one entire day. Track the path of the sun and watch for “microclimates”, that is, areas that may receive direct sun for even 1 or 2 hours a day. Note which time of day the sun may hit the plants. If you are planning your garden in the winter, you will have to imagine how much shade the leaves of the trees will cast as well as realizing that the angle of the sun changes in the summer (it is much higher in the sky). Here are some basic definitions that I use as a guide:

a. Light shade means that you have either shade for 2-3 hours in the middle of the day during the hot summer months, or that the garden receives very bright, dappled light all day long. This is common under very high canopied oak trees.  This is actually pretty close to a sun situation and most sun plants will tolerate this slight degree of shade.

b. Filtered shade means that the plants are growing under a canopy that offers equal sun and shade to filter through. This is an ideal shade condition because you will never get the burning rays of the sun on the plants but it will not be so dark that plants will stretch or compromise their blooming. This situation is often found beneath birches, honey locust, mountain ash, etc. Some plants not listed for shade will grow well here. Test the limits of plants, experiment.

c. Half shade provides 4-5 hours of shade during the middle of the day alternating with sun most of the morning and late afternoon. It is characterized by blocks of sun alternating with blocks of shade. A northern exposure is a typical half shade situation if there are no large trees to block the direct sun early or late. This is a decent situation for partial shade plants because they stay compact, don’t stretch, yet avoid the hot burning direct sun.

d. Full shade means that plants are in the shade ALL DAY LONG. This is common under a rather dense canopy of large mature trees with solid (not lacy) leaves. You definitely want to grow ONLY SHADE PLANTS in this situation.

e. Deep shade can be found beneath large evergreens, decks, steps, or huge overgrown shrubs, on the north side of tall buildings closed in by tall trees, etc. It is very difficult to grow plants in this situation. There are a few plants (marked with * on the plant list) that will tolerate this, but you may want to simplify the design, use mulch or hardscaping, pathways, etc. REMEMBER, NO PLANTS CAN GROW WITH NO LIGHT! Plants need light for photosynthesis

2. Modifying the Shade in your Yard

You can do something about the amount of shade that you have. Thin out trees that are growing too close together. It will help the trees that remain to grow stronger and healthier as well as letting some filtered light in. Limb up the trees to allow in morning or late afternoon sun. This may allow you to grow plants in the LIGHT SHADE or DAPPLED SHADE category in some parts of an otherwise full shade garden

3. Dealing with Tree Roots

Contrary to popular belief, the soil beneath trees is normally NOT rich and moist – it is the first spot in a garden to dry out and is called STARVATION SOIL because the tree roots suck up all of the water and nutrients from the perennials, ground covers, annuals, and shrubs below. Digging beneath trees can be hard work and very frustrating. I use a grub axe and chop right through many of the smaller tree roots to create a proper planting bed. I then heavily amend the soil with LOTS of compost and organic fertilizers and mineral powders to give the plants a good head start. Most books say to not chop the roots of the trees, but my experience is that if you chop the roots and then amend, the trees don’t suffer at all. NEVER ADD TOPSOIL AROUND THE TRUNKS OF THE TREES! You can add topsoil/compost to the bed to make planting easier, but don’t cover the tree trunks or you will girdle the bark and kill the trees.

4. Special Care of the Shade Garden

Because of the root competition, you will have to water much more often. In a drought, you must be constantly aware that your shade garden will need watering. It only takes a couple of days in a dry, hot, windy weather to wilt an Astilbe to death! Installing soaker hoses beneath thick mulch helps a lot in this regard. The soil beneath trees needs amending every year with compost and organic fertilizer to keep the organic matter content high. Slugs love moist, shady conditions so use preventative measures such as diatomaceous earth, course sand, slug traps with beer or yeast bait, etc. to prevent the problem before it starts.

5. Use White or Light Colored Flowers and Variegated Foliage Plants

Dark purple, deep blue, red, or maroon flowers in a dark, shady spot don’t show up. Whites, pale creamy yellows, and light colors jump out at you in the shade. If you want to use the darker colors, back them with variegated foliages or lighter colored flowers that bloom at the same time! Burgundy foliage plants disappear into the background. Surround them with variegated foliages as well.

6. Pay Attention to the Structural/ Textural Characteristics of the Plants

The secret of a good garden design is that it can look magnificent even if there isn’t a single flower in bloom! In a shade garden, if you really pay attention to the foliage shapes and textures and combine them well, they will form a beautiful backdrop to all of your flowers, add drama, and be an important design element in themselves. A single giant leafed bold heavy textured Hosta set amongst a sea of delicate Japanese Painted Ferns can be breathtaking because of its textural contrast. The possibilities are limitless.

7. Take Advantage of the Cooling Effects of Shade

A shade garden is a welcome cool, soothing oasis on a hot, muggy summer day. This can be a tremendous asset when planning your yard as an outdoor living space. Be sure to include a sitting area, benches, etc. so that you can hang out and enjoy the shade that your yard offers. Highlight the effect with a fountain, garden pool, or other water feature. Hang a hammock between the trees with a view of your shade garden.

8. Create a Secret Garden Spot

A meandering pathway that winds its way through the trees to a shady retreat has an element of mystery that will make even the smallest yard seem larger. It’s not always necessary to see your entire garden at once. Create “areas of tension” by not letting your visitors see what’s around the bend. When they venture beyond the stand of Rhododendrons and come upon your secret shade garden, they will be enchanted. (It’s also a good place for YOU to escape and read a good book on a hot summer day!)

 

In an effort to provide horticultural information, these educational documents are written by Nancy DuBrule-Clemente and are the property of Natureworks Horticultural Services, LLC.  You are granted permission to print/photocopy this educational information free of charge as long as you clearly show that these are Natureworks documents.