Light Requirements

Light Requirements

Light is one of the three basic components required for healthy, sustained growth. But how much light is too little? Or too much?

Light requirements for garden plants can range from shade, and part shade, to full sun. Full sun is designated by a minimum of eight hours of direct sunlight, with a preferred ten to twelve hours. Part shade is designated by four to eight hours of sunlight per day.

Direct sunlight is defined as unimpeded light rays reaching plant foliage without clouds, trees, or the edges of a planting container screening or blocking light. Indirect light, especially through a window can sometimes still seem like bright, direct light, however frequently that light is secondary brightness caused by ambient light filtering through a window. Indoors this phenomena can occur when the sun is being obstructed by a roof line or because the sun is directly above or behind the building. If your plants are unable to “see” the sun from their location, they are not receiving true direct sunlight and may instead be receiving indirect, or ambient light.

If you plan to grow your garden exclusively indoors or have yet to decide where your garden will be located, check out our blog post discussing indoor vs. outdoor gardening

Vegetables, greens, and herbs almost exclusively require full sun conditions, with the exception of a few varieties that can grow in part shade or indirect light conditions while still preferring full sun locations. The part shade tolerant varieties offered in Seedsheet gardens include arugula, broccoli, cauliflower, beets, and carrots.

The most crucial time for plants to receive the direct sunlight they require is shortly after sprouting. This is why it is very important to move your garden to an area with 8-12 hours of direct sunlight as soon as a single pod of seedlings has reached one inch in height. It is completely normal and expected for other seed pods to be much smaller or have yet to sprout (see our blog on germination times).

If your seedlings are thin, spindly, and floppy without a lot of foliage development, this is a clear indication that your baby plants are not receiving enough sunlight. Healthy seedlings of most varieties, can support themselves and are generally stouter with greater foliage development. In the photo comparison below, these Mini Salad gardens are the same age and have had exactly the same water and nutrient care. The only difference is that the garden on the left was placed near a sunny window, and received inadequate light, while the garden on the right received 9 hours per day of direct sun outside. The garden placed next to the sunny window has tall and "leggy" seedlings that were straining to find enough light. The seedlings in the garden 

Caught early, these symptoms can be reversed by moving the garden to an area of greater light exposure. If the garden is transferred too late into the sunlight it is likely they will not survive the transition. Think of your seedlings as a person (or maybe even a vampire) in a dark movie theater that has run out into a bright and hot summer day. Too much sunlight too quickly will shock the seedlings and they will burn from the sudden change in atmosphere. For more light specific information check out this blog on indoor vs. outdoor growing

The good news is that we have a fantastic guarantee with our product so you can try your green thumb again (this time, with adequate direct light)! Reach out to our Seedsheet Support Team at with a photo of your garden and we will be more than happy to assist.

Comments (2)

Seedsheet Support_

Great question, Ulla! Most of the requirements are dependent on the variety of plants you are growing. I recommend that you check out our Indoor vs. Outdoor Growing blog post for the indoor lighting requirements of specific plants. If you have any further questions, feel free to contact our Customer Support Team via

- The Seedsheet Team

Ulla Bisgaard_

I have an indoor nursery with LED lights. How many w do they need?
I have 2 setup in our small nursery that’s set up in a shower. The lights are 1000w and 3000w.
Also how many hours should I set the timer to?

Thank you,
Ulla Bisgaard

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