Ever read a plant tag and wondered, so what is full sun? What is part shade? Can I count 8 a.m. toward my direct sun? When the plant tag says full sun to part shade, what exactly does that mean? Is full shade like under my deck shade or in my basement shade? How much shade is full shade? So many questions.

Let’s explore.

Light Definitions
  • Full sun – 6 or more hours of direct sun daily, including mid-day sun.
  • Part sun – 4 to 6 hours of direct sun daily, including mid-day sun.
  • Part shade – 4 to 6 hours of direct sun daily, mainly before midday.
  • Full shade – less than 4 hours of direct sun daily; dappled light is best.
Reading The Plant Labels

The first point to consider when shopping for plants is the light-level requirements. You can find that information on the plant tag at the top of the tag above the description. Sometimes the data is written out, and sometimes it is a symbol. The most common mistake new (and old) gardeners make is assuming they can get a plant to “work” in the wrong light setting. The reasoning generally goes like this, “I love crape myrtles. I bet there’s enough sun at the end of the driveway.”

Our desire for a plant outweighs the truth of our actual sunlight. That crape myrtle, which needs parking lot sun (unobstructed all-day sunlight and hot heat), is going to “sort-of” bloom or not bloom at all in that spot, but the homeowner wants it badly enough to try and “make it work.” Do you know that saying, “Bloom where you are planted”? Well, plants don’t read our tags or understand our euphemisms. They only bloom where they are happy. That saying is for us humans. The bottom line? Plants are specific about their needs, and fudging with them reduces their growth, bloom, and health. Yes, you may get a few crape blooms, but nothing compared to the blooms in all-day sunlight.

Light requirements are the first thing you need to get right.

When the Tag Says Full Sun

When full sun is the requirement, that means six hours of direct sunlight to grow and bloom. Don’t forget. We aren’t just talking about blooming plants. Almost all of the conifers need full sun. This is incredibly frustrating for homeowners who want to screen their neighbors, but the area they want to insert evergreens is wooded and full shade. The current trees are deciduous, which means winter exposes everything. But planting evergreens in a forested area won’t work. Trees need to be removed or thinned out to establish the conifers. And for blooming plants, if it says full sun and it’s planted in part shade, expects less or no blooms. Peonies are gorgeous in full sun weighted down with an abundance of fragrant flowers, but in part shade, they look a little pitiful with their one or two blooms struggling to reach the sun.

When the Tag Says Part Sun to Sun

What does part sun to sun mean? It translates to a minimum of four hours of direct sunlight, including midday sun. Part-sun-to-sun plants bloom prolifically in full sun and produce fewer flowers in part sun. Annabelle hydrangea falls into this category. It blooms prolifically in full sun but also gives a good show in part sun. The more shade, the fewer blooms. The more sun, the more flowers. You can’t trick plants into blooming more in part sun. Instead, understand that it will be beautiful but not as abundant if it were in full sun. It’s managing our expectations. What can I expect in this light setting? If you’re hoping for an abundance of blooms, you may need to rethink your spot.

When the Tag Says Part Shade to Shade

Now we move into shade lovers. What does part shade to shade mean? It requires less than six hours of direct sunlight per day. The morning sun (9-1, for example) is perfect. Plants with this requirement (rhododendrons, azaleas, big-leaf hydrangeas) don’t like the intense mid-day heat and especially do not like the baking hot afternoon sun. Put a big-leaf hydrangea in full sun, and you’ll watch it shrivel every afternoon. It screams for water. It may bloom, but it will struggle. Give it the morning sun until about one, and it will thrive. This is the point, to have our plants thriving, not surviving.

When the Tag Says Sun or Shade

These plants are a rarity, but some can handle either situation. Newer cultivars of coleus fit this category. Plumbago (the perennial) is a beautiful groundcover that can be popped into both locations. The goal here is to know the sunlight in your landscape.

What is Full Sun in My Yard?

Some tools will measure the sunlight in your landscape, and those can be useful. But, for gardeners, the best way to discover the light levels in your landscape is to be in it. There is no better way to understand the shade and sunlight in the landscape than to enjoy it. Get outside, sit, garden, mow grass, read a book, and play with the dog. Make a chart of where the sunlight is and for how long. Include the hours of the day and the orientation of the sun. Where is the warmest spot in early spring? Where is the shade in the heat of summer? And, no person wanting to buy plants NOW likes this statement: Study before you buy. You’ll save yourself tons of money and disappointment.

Regional Analysis

Also, consider where you live. If you’re in Columbia, that big-leaf hydrangea is going to need more protection from the sun. In Asheville, less. All of this can be confusing, so take advantage of our staff, who can help you determine what plants will do best in your setting and, even better, introduce you to new plants to try. You may have your heart set on peonies (who doesn’t), but let staff suggest some excellent shade plants for your shady spot, and before you know it, you’ll have all new loves in the plant world.

Written by Cinthia Milner, Landscape Consultant and blog writer. 

B.B.Barns serves Western North Carolina, upstate South Carolina, and Tennessee.