URBANA, Ill. – Growing food is not limited to outdoors in the summer. With some planning, you can grow food indoors throughout the year.
University of Illinois Extension horticulture educators Nicole Flowers-Kimmerle says that before starting an indoor kitchen garden, it is essential to think about what you want to gain by growing food indoors. You might wish to have herbs to give recipes a special touch or boost nutrition for added health benefits.
“Keep in mind the amount of work you want to put into your indoor garden, schedules including your daily routine and time away, and whether your plants will be only indoors or transferred to outside during nice weather,” Flowers-Kimmerle says.
The limiting factor for growing plants indoors is light. Three aspects of light must be considered when planning to grow an indoor garden – light intensity, duration, and quality.
Most plants grown for food need intense, bright light. A south-facing window is a good location for natural light exposure for plants.
Many plants are sensitive to changes in the time they are exposed to light. Light duration affects their growth, flowering, and setting fruit. Supplemental light during the short days of winter will ensure the plants get light for the required time. Plants also need times of darkness. A timer is a helpful tool to help you deliver the proper duration of light to your plants.
Light quality refers to the color of the light. In general, blue-green light is required for plants to have healthy growth. Red-orange light is necessary for flowering and fruit. Sunlight has all the colors of light.
Supplemental light varies depending on the source. Fluorescent lights give off light in the blue spectrum. Incandescent light is in the red/orange spectrum and gives off heat. It is not essential to buy expensive lights for an indoor garden but to understand how to use light resources effectively.
“Providing the proper amount of water is critical for an indoor garden,” Flowers-Kimmerle says. Check the soil for moisture to determine when to water. It is best to keep the soil profile consistently moist. Too wet or too dry can cause stress to the plant.
Good air circulation around plants helps to prevent fungus and disease problems.
Sterile potting media is a good choice for an indoor kitchen garden. Start your garden without worrying about disease or insect pests. Choose media that drains well to help plants thrive.
Wind and insects pollinate food plants outdoors but are lacking in indoor spaces. Some plants such as tomatoes can be pollinated by shaking them to mimic the wind, while others such as strawberries need to have the pollen transferred by hand to mimic insects.
These five herbs are great options to grow indoors: oregano, thyme, lemongrass, chives, and mint. The first four thrive in bright light, but do not tolerate overwatering. Only water when the top of the soil is dry. Growth can be slow during the winter, so harvest leaves sparingly until new leaves form. Mint can tolerate less light and more water. Keep some on hand to add to teas or desserts.
Lettuce, microgreens, tomatoes, citrus trees, and alpine strawberries are all indoor fruit and vegetable options.
A variety of lettuce can be successfully grown indoors. Scatter seeds evenly across moist soil media and lightly cover. Lettuces thrive in cooler temperatures and need less light than other edible plants. Microgreens are packed with nutrition. These delicate plants are best grown indoors where environmental conditions can be controlled.
Patio varieties of tomatoes and citrus trees can be grown in pots with bright light and moist soil. Keep in mind that these plants will need some help with pollination for fruit to form.
Alpine strawberries can grow well in a bright, cool space out of direct light. For fruit, hand pollination is necessary.
There are so many options for growing an indoor kitchen garden. Try one or more to have fresh, nutrient-filled food all year long.
SOURCE: Nicole Flowers-Kimmerle, Horticulture Educator, Illinois Extension.
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