How to Understand Your Yard’s Sunlight So You Know What to Plant Where

Sunlight, water, and soil are the key components of healthy plants. The amount of light your yard gets will change throughout the day as shadows from buildings and tall plants move with the sun. Most plants will thrive in at least six hours of direct sunlight, which is typically referred to as full sun. However, many plants will unfurl fabulous foliage and beautiful blooms in less sun, so you can still create a lush and colorful garden in all but the shadiest conditions. Here’s what you need to do to make the most of every light level in your landscape.

Study Your Yard’s Sunlight

To start, spend some time creating a garden journal, where you can record how much sunlight your yard receives over time. Assess light patterns every hour or two throughout the course of a day, noting where shadows fall and for how long. Keep in mind that in spring, bare-branched trees may give the illusion of sunny spots, but once they leaf out, they can create heavy shade during the summer and into fall. Buildings and walls also cast shadows, so be sure to consider those structures as you plot the sun’s path over your patch of earth.

You can use marking flags or stakes to indicate light and shadow in your yard, or you can create a light map on paper. Starting with a few sheets of tracing paper, sketch a copy of your yard’s outline on each page. About two hours after sunrise, observe where light and shade fall and mark them on the tracing paper, noting the time. Repeat the process throughout the day, each time using a different sheet of paper. Stop recording about an hour before dusk. Use a pencil to mark the shady sections on each page. Label sun and shade pockets to indicate whether they reflect morning or afternoon conditions. Layer the pages together, and you’ll get an accurate picture of how much light your yard receives.

Understand Sun and Shade Areas

Areas that receive sunlight nearly all day are straightforward to work with when it comes to designing gardens and choosing plants. You can count on the intensity of sunlight to vary slightly based on the time of day, with morning light offering softer, gentler rays and afternoon sun blazing.

Shade is a little more complicated. There’s the deep shade you find on the north side of a house, alongside a stone wall or privacy fence, or beneath a 70-year-old beech tree, where the sun only peeps from winter through early spring. Pair these deep shade locations with plants that don’t require direct sunlight to thrive.

Dappled shade can be found beneath trees, where small leaves filter sunlight to cast a shifting glow. Deciduous trees, like maples and ashes, offer seasonal shade, starting out sparse and filling in with a dense canopy that delivers decent shade throughout the summer months. Leafless boughs provide the perfect spot for ephemeral plants, such as bleeding hearts or naturalizing spring bulbs, which produce an early-season flower show, then quietly disappear as tree canopies fill in and shade deepens. As the sun takes an overhead route, shade patterns shift and shorten in summer under deciduous trees and then lengthen as summer moves into fall. These seasonal light patterns are helpful to know as you choose and situate plants for your garden.

Consider Regional Influences

A plant’s light requirements shift throughout the United States. In the Southern heat, sun-loving plants may benefit from shade during the hottest part of the day. Meanwhile, in the Pacific Northwest, cloud cover can prevent sun lovers from flourishing. Where cool, wet summers prevail, plants that nominally prefer partial shade can thrive in sunnier conditions.

Learn Your Plants’ Light Requirements

Most plants have preferred light conditions for top-notch performance, and these are typically described as full sun, part sun, part shade, or full shade. Not sure what these terms mean? You’re not alone. Here’s how to decipher the light code:

Full sun: Plants that require at least six hours each day of direct sunlight.

Part sun/part shade: These terms usually mean the same thing, referring to plants that should receive three to six hours of sun per day, preferably in the morning or evening. The rest of the time, these plants can be in dappled shade or completely shaded.

Full shade: Plants that need fewer than three hours of direct sun per day. This could describe the conditions found on the north side of a structure or under a shade tree, where sunlight briefly penetrates the canopy at some point during the day.

Try Removing Some Shade

When planning out your landscape, it’s important to remember that many things—available light included—are flexible. If you have a tree with branches that are casting dense shade, lighten the area below by removing lower limbs. This process, called limbing up, effectively lifts a tree canopy, allowing more sunlight to penetrate below. During late summer and fall, sunlight can slant beneath limbed-up trees to lighten the deep shade. Selectively thinning can increase light to the ground below. Similarly, you can also consider replacing solid fences with a vine-covered lattice to increase light.

Remember, Rules Are Flexible

Once you know your garden’s sun and shade characteristics, it’s time to start picking out plants. Keep in mind that, if you happen to place a plant where it gets too much or too little light, you won’t necessarily kill it right away. You’ll likely experience early warning signs, like fewer flowers, a shorter life span, less color, or gangly stems. If an annual or perennial isn’t thriving in a certain location, grab your shovel and transplant it to another spot. Plants are tough; they usually can handle moving from place to place.