I’m eating my houseplants. Or rather I should say I’m growing plants indoors that I can eat. Herbs, greens, and some vegetables can be successfully grown in your home if you can address the basic needs of your plants.
Temperature & Location
The outdoor growing season starts when soil temperatures reach a plant’s optimal range. Cool-season plants grow best below 70-degrees while warm-season plants prefer temperatures above 70-degrees. Using indoor or sheltered locations allows you to get an early start on the growing season by providing the ideal temperature and matching the location with the plants’ needs. A garage, an outside storage area, or a protected balcony or porch can be a great place for cool-season plants. Place a thermometer near your plants. You may need to cover your plants or use a heat mat to keep nighttime temperatures from dipping too low.
You can extend the growing season in spring by starting plants indoors and then transitioning them outside once conditions match their needs. As our days warm up, plants can be moved from warmer indoor locations to cooler protected outdoor spaces, and then to outside beds. In selecting your site, remember it’s easier to tend to those plants situated in convenient locations, as nearby access to water and other materials makes maintenance simpler. NC State University has an online planting calendar with dates for planting outdoors.
Most of the plants we eat need six to eight hours of full outdoor sun to grow. South-facing windows may provide that much if they are not blocked by trees or structures. Lacking adequate light indoors, you can supplement with incandescent, fluorescent or LED lights. Set the light source on a timer for 12-16 hours. More intense light will help keep young plants from becoming leggy. Place the plant closer to the light source and then back away as it matures. Brown leaf edges may suggest the plant is too close to the light source while pale or smaller leaves may indicate the plant is not getting enough light.
Water, Soil, and Tools
Moisture is essential to germination and development of young plants. Too little water prevents plants from getting started but too much water and young plants will likely succumb to disease. It is essential you achieve the correct balance of moisture and drainage. It sounds contradictory, but it isn’t. Allowing containers to dry out will stress young plants, so develop a watering routine that keeps the growing medium moist, but not soggy. Warm locations will dry out pots more quickly and small containers tend to dry out faster than large ones. City tap water often contains chemicals, which can be hard on young plants. Pour water into a clean container and let it sit uncovered for at least 24 hours before using on your plants, as this allows the chlorine and other chemicals to dissolve and dissipate.
While many containers, locations, and growing mediums can work they all need to be free of pests and contamination. Pests can hide in pots brought indoors for the winter, and recycled plant containers can harbor pathogens. Sterilize containers before reuse by soaking in one part bleach to nine parts water for at least 10 minutes. Tools, materials, and our hands can transfer pests and pathogens among plants, so spray or wipe your hands, tools, and materials with disinfectant when moving from one group of plants to another.
Starting plants indoors allows you to get a jump on the growing season. Check out our podcast at TriangleGardener.com for reviews of useful tools and other tips that can help you succeed at indoor gardening.
Dr. Lise Jenkins produces the Triangle Gardener’s radio show and podcast. She also volunteers her time as a Master Gardener in Durham.