When we talk about gardening outdoors we usually use different terminology than we do for indoor gardening, here we will discuss both and how this translates to your gardening experience. It's no secret that plants need light to grow, but how they get that light and how much depends on the plant you are growing. Some plants are more forgiving and will tolerate nearly any amount of light while others have very specific lighting needs. We're also going to discuss light spectrums and how those influence plant growth and production, since plants use different wavelengths of light to grow and to produce flowers and fruit.
Direct/Full Sun:
Plants receive 6+ hours of direct sun - meaning nothing like other plants, hard scaping or architecture is casting a hard shadow or blocking their view of the sun during that time. Many fruits and vegetables require 6+ hours of direct sunlight to be happy and healthy translating into good production of edible plants. Open yard spaces like the grassy area in the photo above are the best place for full sun plants.
Let's take a closer look at the example below - most of these plants can see the sun directly, and none of them is so tall that they block out the sun or cast a hard shadow blocking out the light to other plants. Hard scaping such as stones are low to the ground. There are no trees, fences, or structures next to them.
Full Sun gardens can be simple or elaborate, but they all share wide open spaces for light to reach plants directly for a good portion of the day. So is it possible to have full sun next to a structure or other plants? Certainly! But - that depends on which direction the sun rises and sets. Full Sun gardens enjoy direct light from the east for plants more sensitive to drought, and from the noonday sun to the west for plants which are more drought tolerant.
Here are some real life Full Sun gardens:
Partial Sun:
Plants receive more than 3 and less than 6 hours of direct sun, they still have an uninterrupted view most of that time - shadows from surrounding plants, hard scaping or architecture may obscure their view but usually don't cast hard shadows on them directly.
Before we look at an example photo below were going to take a moment to discuss partial shade and sun light intensity. Trust us - it will help put the two terms into much better prospective.
Partial Shade:
This term is a lot like partial Sun, usually 2-6 hours of sun, but we're going to differentiate them here by talking about timing and intensity when we're thinking about partial shade, ideally partial shade is going to be morning sun followed by some afternoon shade - shadows from surrounding plants, hard scaping or architecture do obscure their view and may cast hard shadows on them.
We're looking for afternoon shade for most plants that like partial shade because that is when the sun's rays are the most intense which may burn more delicate plants in even a short amount of time without protection from surrounding plants, hard scaping and architecture. In most places that means we want them to get morning sun so placing them on the eastern side of protective plants and spaces is key to success.
Look at the example photo below for part sun/part shade - some taller shrubs and hard scaping provide a little shade for part of the day, but do not obscure direct sunlight the entire day on the left or western side, this is part sun. Other plants and architecture protect the plants on the right or eastern side, this is part shade.
Remember from earlier that shade and when it occurs during the day can help us choose where to place plants that are more or less drought tolerant - by placing plants in spaces that help conserve moisture in both the soil and the plant itself we can assist our plants in growing and prevent wilting during the height of summer heat.
Here are some real life half sun-half shade gardens:
Full Shade:
When we talk about full shade we are very rarely thinking about dense forested spaces which block out light entirely - we're looking at spaces which get 2 hours or less of direct sunlight but still recieve bright indirect light or dappled light throughout the entire day. Full shade is not the absence of sunlight but more about how that light is delivered.
Let's look at the photo below, notice how dense the landscaping is and the shadows cast by architecture and taller landscaping and hard scaping - the shadows cast by these things doesn't prevent all sunlight from reaching the rest of the garden, but it does keep direct sun from scorching more delicate shade lovers.
Understory plants which like shade are good choices for these types of gardens planted under and around their taller counterparts. Alternately many shade gardens tend to grow native species naturally underneath taller shrubs and trees.
Here's some more real life shade gardens
Next week we will upload part 2 - indoor garden lighting:
https://plantywoo.com/blogs/plantywoo-science/how-does-your-garden-grow-light-indoors-part-2-3