While outdoor gardening is preferable (plants love natural sunlight), indoor growing can achieve similar results with some environmental adaptations (hello, fresh herbs directly on your kitchen counter!).
Because indoor conditions are generally climate stable and safe from marauding critters, we recommend ideally starting Seedsheet gardens indoors for germination purposes, then moving the container outside into direct sunlight as soon as one pod of seedlings has reached 1-inch in height. It is totally normal and acceptable for other pods to be smaller or ungerminated at the time of transition.
If you plan to grow exclusively indoors either due to the season or limitation of outdoor space, the biggest factor to consider is light. Plants need direct light (either sunlight or artificial grow light) to develop foliage and produce healthy plant material that is harvestable. Also consider the temperature directly next to a window, either overly cold or hot can have adverse effects.
Some varieties are more difficult to grow to maturity indoors than others. Greens, herbs, and root vegetables can all be supported easily indoors. Fruiting vegetables like peppers and eggplant require greater care but can be cultivated indoors (see our blog on hand-pollination!). Fruiting vegetables like tomatoes, or vining fruiting plants like cucumbers and melons require much greater space, care, and light indoors.
First, determine if you have adequate natural light indoors. A south-facing window is preferred with a minimum of eight hours of direct and full sunlight. This can sometimes be difficult to judge, as even though a window may be sunny, often it is not receiving direct sunlight as the light is coming in at an angle or from overhead. Furthermore, if you are located in the northern half of the United States during the fall and winter months, consecutive grey and overcast days can be detrimental to plant production. Situations like these will require supplementing the natural light with a full-spectrum LED grow light.
When selecting an LED grow light the size of your gardens and the variety of plants you are cultivating should be considered. A mini Seedsheet garden, with non-fruiting plants (herbs and greens), requires less light support than a larger container garden with non-fruiting plants. Also, more wattage will be required if you have multiple gardens to support.
Our LED light recommendations are as follows:
- Mini Garden- 75W
- Consider this light: Bozily 75W LED Grow Light with built-in timer
- Balcony Container Garden with greens and herbs- 150W
- Consider this light: Cobshop 150W LED Grow Light
- Balcony Container Garden with smaller fruiting plants (peppers, eggplant, etc.)- 600W
- Consider this light: Roleadro 600W LED Grow Light
- Balcony Container Gardens with large fruiting plants (tomatoes, cucumbers, squash, melons)- 1200W with a large area span, or two 600W lights spaced appropriately.
- Consider doubling up on the 600W light above, or selecting this light: Roleadro 1200W LED Grow Light
Lights should be set on a timer for 12 hours per day and should be hung from directly overhead, 6-12 inches away from foliage so as not to burn the leaves.
Inadequate light symptoms display as tall, thin, stringy seedlings that are “leggy” and floppy (like the garden below) and direct light should be increased immediately. For more information, check out our blog on light requirements.
The final factor to consider is your indoor environment. Your garden may be small when planted, but the plant material above the soil surface will expand exponentially as time passes. Providing enough space for air flow around a plant (or adding a small fan) will allow your garden to grow to full potential and prevent any development of diseases and pest infestation. Also, consider the humidity and temperature of the area and avoid growing in a dank basement or unheated garage.
Check out the video clip below from an episode of Seedsheet Live!