Quick answer
Sun exposure for landscape plants is the amount and timing of direct sunlight a spot gets in a day, usually grouped on plant tags as full sun, part sun, part shade or shade, so you can match a plant to the light it needs.
The groups are counted in hours of direct sun, but no single national standard sets the cutoffs. Extension offices draw the lines in slightly different places.
Quick facts
The key facts about Sun Exposure for Landscape Plants, with sources:
- Full sun
- At least 6 to 8 hours of direct sun a day, per University of Illinois Extension; six or more hours of summer sun including afternoon, per University of Maryland Extension 12
- Part sun
- 4 to 6 hours a day, usually morning or late afternoon, per Illinois 1
- Part shade
- 2 to 4 hours per Illinois; 4 to 6 hours with the sun before midday per a Maryland Extension Master Gardener article 12
- Full shade
- Less than 2 hours of sun per Illinois; no more than 4 hours of filtered or morning sun for shade plants per Maryland 12
- Hardest exposure
- Southern exposure is the harshest and northern the kindest; west gets intense afternoon sun and east gets cooler morning sun 2
Key takeaways
- Light categories are counted in hours of direct sun, not in how bright a spot looks. Direct sun means sun that reaches the plant without a tree, roof or wall in the way.
- The same words cover different hours. Illinois puts part shade at 2 to 4 hours, while a Maryland Extension article puts part shade at 4 to 6 12. Read the tag’s own definition.
- Time of day matters as much as the total. Morning sun is cooler, and afternoon sun is hotter 2. Many shade-loving plants tolerate morning sun if the soil stays moist 6.
- Measure your spot instead of guessing. Washington State University suggests mapping sun and shade at 9 a.m., noon and 3 p.m. 9.
- Sudden changes scorch plants. A plant moved from shade to full sun, or left exposed when a tree comes down, can burn 6.
Light as a plant requirement, not a mood
Every plant sold for a yard has a light need. Sun-loving plants make food from strong light and may stop blooming or fruiting without it.
Mississippi State University says full-sun plants need six to eight hours of direct sunlight to keep blooming or fruiting 3. Shade plants often have thinner leaves that gather weaker light.
A Maryland Extension Master Gardener article notes that shade-lovers tend to have thinner foliage with more surface area and more chlorophyll, which helps them harvest light at lower levels 2.
The four common labels are full sun, part sun, part shade and shade. Some tags show a range such as “full sun to part shade.” The label describes the light a plant tolerates well, not the light it merely survives.
This page covers light only. How cold a place gets is a different question, answered on plant hardiness zones. How far apart to set plants is on plant spacing. For a planting job, read our planting and garden beds guide.
Why one yard has many kinds of light
Direction. In the northern hemisphere, southern exposure is the harshest because the sun is on it most of the day, and northern exposure is the kindest. Western exposure gets the intense afternoon sun, while eastern exposure gets bright but cooler morning sun 2.
Trees and buildings. Mississippi State describes dense shade under broad-leaved trees such as southern magnolia, oaks and maples. Light shade or filtered light comes from high-branched trees such as pines.
Part shade is an area that gets full sun for part of the day, such as next to a building or at a woodland edge 3.
The same source notes that deciduous trees let winter sun through their open branches.
Slope. Washington State University explains that in the northern hemisphere south-facing slopes get more direct sun and run warmer. This applies even to small slopes in a yard 9.
Reflected heat. Oregon State University advises avoiding reflected heat when siting bigleaf hydrangea in western Oregon 7. Light-colored walls and paving can bounce heat onto plants.
- Compass directionSouth is harshest, north is kindest, west gets hot afternoons 2
- Trees and shrubs overheadBroad-leaved trees give dense shade; high-branched pines give filtered light 3
- Buildings and fencesThey cast shadows and can reflect heat back onto a bed 37
- SlopeSouth-facing slopes are warmer 9
- SeasonOpen winter branches let sun through; summer leaves block it 3
Layers follow the Maryland, Mississippi State, Washington State and Oregon State sources. They stack: one bed can be affected by all five. Source: [2] [3] [9] [7]
The four light labels, as three extension sources define them
| Label | University of Illinois Extension | Maryland Extension (Frederick County Master Gardeners) | Mississippi State University Extension |
|---|---|---|---|
| Full sun | At least 6 to 8 hours of direct sunlight a day 1 | Six or more hours of summer sun a day, including afternoon sun 2 | Six to eight hours of direct sunlight for sun-loving plants to keep blooming or fruiting 3 |
| Part sun | 4 to 6 hours of direct sun, usually morning or late afternoon 1 | 4 to 6 hours; plants better tolerate some of those hours in the afternoon 2 | Not defined |
| Part shade | 2 to 4 hours of direct sun, usually morning or late afternoon, with less intense light 1 | 4 to 6 hours; plants prefer the hours before midday 2 | An area that gets full sun for part of the day 3 |
| Full shade or shade | Less than 2 hours of sun a day; dappled or deep shade 1 | No more than 4 hours of sun, filtered or limited to the morning 2 | Dense shade under broad-leaved trees; light shade or filtered light under high-branched trees 3 |
Part sun and part shade are not the same thing
Illinois separates part sun (4 to 6 hours) from part shade (2 to 4 hours) 1.
The Maryland article gives both as 4 to 6 hours and splits them by time of day: part-sun plants tolerate afternoon hours and part-shade plants prefer the hours before midday 2.
If a tag says only “part shade,” look for the hours or the time of day.
Example: sorting four spots in one yard
The four spots and their hours are invented to show the method. The labels use the Illinois ranges for the hours column and the Maryland note about time of day 12.
| Spot (example) | Direct sun (example) | Label by Illinois hours | Time-of-day note |
|---|---|---|---|
| South side of the house | 8 hours, mostly midday and afternoon | Full sun | Southern exposure is the harshest 2; choose plants that handle heat |
| East bed by the fence | 5 hours, all before 1 p.m. | Part sun | Morning sun is bright but cooler 2 |
| West side behind a shed | 3 hours, late afternoon | Part shade | Afternoon sun is hotter than morning sun 2; watch for scorch |
| North side under a maple | 1 hour, filtered | Full shade | Dense shade from a broad-leaved tree 3 |
The east bed and the west bed get different hours and different heat, so one plant list will not fit both. Count the hours across a day, then check the time of day. WSU’s method is covered in the steps below 9.
How to measure your sun, step by step
The is below a homeowner’s reading order built from the Washington State University handout and the Maryland and Illinois pages.
- Pick the planting spot and sketch it. Include trees, buildings and fences that cast shadow.
- Map the light three times in one day: 9 a.m., 12 p.m. and 3 p.m. Washington State University says to repeat this at the beginning, middle and end of the growing season 9.
- Count the hours of direct sun. Shade from a tree or wall does not count as direct sun.
- Note when the sun arrives. Morning-only and afternoon-only spots with the same hours behave differently 2.
- Compare your count with the tag’s hours, using the table above. If a tag gives only a label, ask the nursery which definition it uses.
- Write down drainage, wind and protected spots on the same sketch. WSU lists them as part of the same map 9.
Where the term shows up: tags, designs, bids and warranties
Plant tags. Maryland Extension says labels often indicate full sun, partial sun, partial shade and shade, or a combination 2. Containers need plants with the same light need, the same article notes.
Planting plans. A designer may place plants by sun and shade zones on a plan. See landscape bed preparation for what comes before planting.
Bids and warranties. A plant warranty may exclude plants set in light that does not match the tag. Read the terms on the plant warranties page and check how a company judges site light on our estimates guide.
Lawns. Grass has light needs too. Mississippi State says St. Augustine grass, the most shade-tolerant lawn grass in its list, still needs at least half a day of sun 3. See cool-season vs. warm-season grass.
What matching light does well, and what it cannot fix
What it does
What it cannot do
- Cannot fix poor soil, bad drainage or a wrong zone. Oregon State says sun-loving plants planted in shade will not thrive, and it also says standing water is a problem for almost all plants 8.
- Cannot make an exposure cooler. A west wall still gets hot afternoon sun 2.
- Hours are a rough count. Cloud, season and tree growth change the real light.
Limits and open points
No shared definition. The Illinois, Maryland and Mississippi State pages disagree on part shade and on how to define shade 123. A plant that is “part shade” on one tag may not match the hours on another.
Sun is not the only factor. Climate decides how much sun a plant can take. The same Maryland article says a full-sun annual in Maryland may not be as happy as one planted in Maine at the height of summer, and may need more frequent watering on intense days 2.
Plants differ by cultivar. Two cultivars of one species can have different light needs. Check the tag for the exact cultivar.
We give no plant lists. Light-tolerant plants vary by region. Your local Cooperative Extension office can give a list for your area.
What drives the cost of fixing a light problem
We do not print prices on a glossary page. These choices change a bid.
Change the plant. Picking plants that fit the light you have is usually less work than changing the light. A plant that fails in the wrong spot must be replaced.
Change the light. Thinning or removing branches, or removing a tree, adds sun. Those jobs are priced by size, access and risk. See the tree removal cost tool and tree service.
Add shade. A fence, a screen or a structure can shade a hot bed. Materials and labor vary by design.
Replacement terms. How a company handles a plant that fails in the wrong light is a warranty question. See the cost hub.
We found no source for how long plants last in a given light, so we give no lifespan.
Keeping the match: moving plants, watering and checking again
Light in a bed can change over the years. Trees and shrubs grow, and a new fence or building can cast new shade. Re-check your map when a bed looks different.
Water matters more in strong sun. Maryland Extension says sunburn symptoms are more severe when strong sun is combined with dry soil, and that shade-loving plants tolerate morning sun if the soil stays moist 6. For ground covers it advises keeping soil moisture steady during the growing season to reduce scorch 6.
If a plant is in the wrong light, you can move it. Read transplanting landscape plants first.
Mulch helps hold moisture in hot beds. Oregon State recommends deep mulch for hydrangeas in the hot summers of southern Oregon 7. See mulch types.
Warning signs of the wrong light
Too much sun. Maryland Extension describes sunburn as pale, bleached or faded areas that turn brown and brittle. Leaf margins and tips may scorch in drought. It often follows a sudden change, such as tree removal or moving a plant from shade to sun 6.
Too little sun. Sun-loving plants may stop blooming or fruiting without six to eight hours of sun 3. Weak, stretched growth is a common sign, though we did not find a source that quantifies it.
When to get help. A plant that keeps failing in a spot may have another problem, such as drainage or compaction. Ask your Cooperative Extension office. For hiring, read how to choose a landscaping company.
Do not trim or remove a large tree yourself to get more sun
Cutting branches to add light is tree work. Climbing, chainsaws and branches near power lines are dangerous, so hire a qualified arborist. Check your city’s rules first on the tree removal permit page, and call 811 before digging any new planting hole.
What is advice, and what is a rule
| Topic | What is stated | Type | Source |
|---|---|---|---|
| Sun and shade labels | Hours differ by source; no national standard found | Extension and trade practice | Illinois, Maryland, Mississippi State 123 |
| Plant tags | Often label full sun, partial sun, partial shade and shade, or a combination | Trade practice | Maryland 2 |
| Tree pruning or removal to add light | Set by city, county or HOA | Local rule | See the permit research |
| Fence or structure for shade | Setbacks and height are local | Local rule or HOA | Check locally |
Sun exposure compared with related terms
| Term | The difference | Where to read more |
|---|---|---|
| Sun exposure (this page) | How many hours of direct sun a spot gets and when | You are here |
| Hardiness zone | How cold winter gets; says nothing about light | Plant hardiness zone |
| Drought tolerance | How well a plant handles dry soil; many sun plants need heat and dryness | Drought-tolerant plants |
| Shade-tolerant ground cover | Low plants chosen for places grass will not grow | Ground cover plants |
| Tree thinning | Removing branches to let light through | Crown thinning vs. reduction |
Myths about plant light
- Myth Part shade and part sun mean the same thing.
- Reality Illinois gives them different hours, and Maryland splits them by time of day 12.
- Myth Six hours of sun is six hours of sun, whatever the time.
- Reality Afternoon sun is hotter than morning sun, and most shade-loving plants tolerate morning sun if the soil stays moist 26.
- Myth Shade plants never need much light.
- Reality They need the amount their label gives. Mississippi State notes that even the most shade-tolerant lawn grass needs at least half a day of sun 3.
- Myth A full-sun plant is full sun everywhere.
- Reality Climate changes the answer. Oregon State advises afternoon shade for bigleaf hydrangeas in hot southern Oregon but morning sun with afternoon shade elsewhere in the state 7.
- Myth Sun problems are always about sun.
- Reality Maryland Extension says leaf scorch is worse when soil is dry 6. Water and soil matter too.
What changes by region: how hot the afternoon is
The regional variable is how strong the afternoon sun is. Oregon State University’s hydrangea advice shows the shift in one state. Western Oregon: morning sun with afternoon shade and no reflected heat.
Southern Oregon, with hot summers: prioritize afternoon shade and deep mulch. Central Oregon high desert: morning sun and afternoon shade, with shelter from prevailing winds 7.
These are one plant’s notes in one state, not rules for every plant. Ask your local Cooperative Extension office how your region treats full sun, and see the hardiness zone page for cold.
When to measure, and your next step
Measure sun before you buy plants, before you build a raised bed, and after any tree comes down. It is the cheapest step in a planting plan.
Your next step is to map the spot at 9 a.m., noon and 3 p.m., count the direct hours and note the time of day.
Then match the count to a plant’s tag, and ask the nursery which hours its labels mean.
For a bed that holds food, see raised garden beds for how a bed’s sun, soil and frame fit together.
If you want help with planting, find a landscaping company. HyreYard does not plant or sell anything.
- If 6 or more hours, including afternoon
- Then Full sun plants; choose heat tolerance for a south or west exposure 2
- If 2 to 4 hours, morning or filtered
- Then Part shade plants per Illinois 1
- If Under 2 hours or dense tree shade
- Then Shade plants per Illinois; expect root competition from trees 13
- If A sudden change in light
- Then Expect scorch; acclimate plants and keep soil moist 6
Questions about Sun Exposure for Landscape Plants
What does full sun mean for plants?
Full sun means at least 6 to 8 hours of direct sunlight a day, according to University of Illinois Extension. A Maryland Extension article defines it as six or more hours of summer sun including afternoon sun. Southern and western exposures usually fall in this group.
What is the difference between part sun and part shade?
Illinois Extension says part sun is 4 to 6 hours of direct sun and part shade is 2 to 4 hours. A Maryland Extension article gives both as 4 to 6 hours. It says part-sun plants tolerate some afternoon hours, while part-shade plants prefer the hours before midday.
How many hours of sun is full shade?
It depends on the source. Illinois Extension says full shade is less than 2 hours of sun daily. A Maryland Extension article says shade plants are happiest with no more than 4 hours of sun that is filtered or limited to the morning. Check the tag for its own hours.
Is morning sun or afternoon sun better for plants?
Morning sun is bright but cooler, and afternoon sun is hotter, according to Maryland Extension. Most shade-loving plants tolerate morning sun if the soil stays moist. Strong mid-day sun can scorch them, and damage is worse when the soil is dry.
How do I measure sun in my yard?
Washington State University suggests mapping your garden three times in one day, at 9 a.m., 12 p.m. and 3 p.m., at the start, middle and end of the growing season. Note sunny and shady parts, drainage, wind and protected spots. Count only hours of direct sun.
How much sun do vegetables need?
Clemson Extension says gardens in South Carolina should get at least six hours of direct sun each day. Leafy crops tolerate partial shade, but fruiting crops such as peppers and tomatoes need full sun.
Why did my shade plant burn?
Maryland Extension says sunburn often follows a sudden change in exposure, such as tree removal or moving a plant from shade into sun. It looks like pale, bleached areas that turn brown and brittle. Drought makes it worse, so keep the soil moist and choose plants suited to the light.
Can a full-sun plant grow in part shade?
Some can, for example plants labelled full sun to part shade, but results vary. Oregon State says sun-loving plants planted in shade will not thrive. Mississippi State says sun-loving plants may stop blooming or fruiting below six to eight hours. Check the tag and your local extension office.
Does sun exposure change with the seasons?
Yes. Washington State University suggests mapping light at the start, middle and end of the growing season. Mississippi State notes that deciduous trees let winter sun through open branches. A spot shaded in summer can get sun in winter, which matters for evergreens and winter care.
Does the hardiness zone tell me how much sun a plant needs?
No. A hardiness zone covers winter cold only. Light, water and soil are separate questions. A plant can be rated for your zone and still fail in the wrong sun. Use both: the zone to rule plants out for cold, and your sun map to match the spot.
Sources
- University of Illinois Extension, Gardening Terms Defined (March 6, 2025), retrieved .
- University of Maryland Extension, Frederick County Master Gardeners, Seeing the Light of Day (Denise Morrow, 2022), PDF read as text with pdftotext, retrieved .
- Mississippi State University Extension, Successful Shade Gardens (Robert F. Brzuszek), retrieved .
- Clemson Cooperative Extension HGIC, Planning a Garden (HGIC 1256, revised February 12, 2021), retrieved .
- Colorado State University Extension, Perennial Gardening (reviewed August 2025), retrieved .
- University of Maryland Extension, Sunburn Damage on Flowers (updated March 7, 2023), retrieved .
- Oregon State University Extension, Hydrangeas bring beauty and variety to Oregon gardens (Kym Pokorny, June 2024), retrieved .
- Oregon State University Extension, Drought-tolerant landscape plants for Western Oregon: site selection and preparation (Heather Stoven and Neil Bell, July 2024), retrieved .
- Washington State University Extension, Skagit County Master Gardeners, Microclimates (Claudia Wells, June 7, 2019), PDF read as text with pdftotext, retrieved .
Expert review
Written by the HyreYard Research Desk. Not yet reviewed by an outside expert. We say so rather than imply a review that has not happened; see our editorial policy.
How the numbers were checked: Hour ranges come from three extension pages that disagree, so the page prints them side by side. Illinois, Mississippi State, Clemson, Colorado State, Oregon State and the Maryland sunburn page were read as web pages.
The Maryland Frederick County article and the Washington State microclimate handout are PDFs read as text. The University of Minnesota page was blocked (HTTP 403), so it is not cited. The worked example uses invented spots. We give no plant lists or planting dates.
Suggest a correction. We fix errors and say what changed.