Light Levels for Outdoor Plants

Understanding Light Levels in Your Garden

You pick up a plant and notice the plant tag says “part shade” but what exactly does that mean? Full sun, part sun, part shade, full shade are the most common ways that you will see plants labeled. So how much light does your outdoor plant need?

If you picked up that Hosta and put it in the front of your house in full, hot afternoon sun then you will find that your Hosta looks burnt, small, and it may even die. Why? Because most Hostas prefer part shade to full shade. Here are the main 4 sunlight categories:

  • Full sun – more than 6 hours of direct sun per day including plenty of afternoon. These plants want plenty of sunlight.
  • Part sun – 4 to 6 hours of direct sun per day, including some afternoon sun. The amount of sun doesn’t need to be consecutive and can fall morning and then afternoon again later.
  • Part shade – 2-4 of direct sun per day, mostly before midday to avoid the harsh afternoon rays.
  • Full shade – less than 3 hours of direct sun per day. These plants do need at least a couple hours of sun or bright light to thrive but it’s best that these are the cooler morning rays of sun. There are some varieties that will tolerate zero sun though not as many.

How do you figure out how much sun you have? The simplest way is to simply write a note in your phone and observe early morning, mid morning, early afternoon, midday afternoon, evening sun. Check the area at each increment of the day and make a note of whether there is sun or not. This will help you pinpoin what plants will go best in which areas.

In addition, plant labels can vary in how they are listed so you may see terms such as:

  • Part sun to sun  – Plant will tolerate full or part sun but will likely bloom best with the most sun. (Daisy, Lantana, Sedum)
  • Part shade to shade  – Less than 6 hours of sun and try to make most of those in the earlier part of the day. You will find that a lot of part shade to shade are grown more for their ornamental foliage and don’t bloom as much. (Think: Begonias, Coral Bells, Hostas)
  • Sun or shade – 2-4 of direct sun per day, mostly before midday to avoid the harsh afternoon rays. (New hybrid varieties made to tolerate both)

Other light questions? Feel free to reach out to us!

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