A few sprigs of fresh, aromatic basil (Ocimum basilicum) can take a dish from good to great. But keeping fresh herbs around can get expensive, and it’s easy to let a whole bunch go bad if all you need is a few leaves for a recipe. That’s why the best way to enjoy fresh basil all summer long is to grow it yourself.
Aside from the classic Italian Genovese basil called for in pasta, pesto, and tomato sauce recipes, there are several different varieties. Thai basil is a must for curries, noodles, soups, and lettuce wraps, while holy basil or tulsi, Ocimum sanctum, adds a spicy sweetness to dishes and makes a refreshing tea on its own. With its shiny, purple leaves, opal basil adds delicate flavor and beautiful purple color to salads and other dishes.
Best Growing Conditions for Basil
Unlike houseplants that can survive in low-light conditions, your indoor basil plant will need lots and lots of bright light to grow well indoors. After all, it’s used to full sun exposure when grown outside. This means you’ll need a sunny window, ideally south-facing to get the most light, to grow a basil plant you can keep coming back to for fragrant springs.
Indoor basil should get at minimum six hours of bright sunlight per day. If you don’t have a sunny, south-facing window, you can purchase a fluorescent or LED grow light to use on your plant. With a grow light, 12 hours per day of light is ideal, with the grow light positioned two to four inches away from the plant.
If your indoor basil plant is growing long, leggy stems, that’s an indicator it’s not getting enough light.
Basil is a summer herb, and it thrives in warm-weather conditions. Make sure that the spot you keep your basil plant is away from any cold drafts. Air that’s too dry can also hurt your basil plant, so display it away from hot or cold air vents.
How to Care for Your Basil Plant
Keep your basil plant’s soil evenly moist but not soggy, and be sure to water at the first sign of wilting. If your space is dry, group it with other plants to create a more humid microclimate.
Your basil plant is there to be eaten—which actually helps it grow fuller. Pinch back the top growth on each stem of your young basil plant to help it grow full, then use the leaves in recipes or store them for later. Repot your basil plant as needed, going up one or two pot sizes each time and using an organic potting soil designed for growing vegetables and herbs.
Fertilize your plant during the spring and summer using an organic fertilizer designed for growing vegetables and herbs. Dilute the fertilizer to half-strength and apply it to the soil weekly after watering your plant. Discontinue fertilizing in the fall and winter.
If you have a sunny outdoor deck, patio, or even fire escape, your basil will benefit from being placed outdoors once nighttime temperatures are above 50 degrees. Acclimate the plant gradually to bright sunlight by putting it outdoors in part shade for a few hours each day, gradually adding more time and sunnier conditions until it’s ready to live outdoors full-time for the summer.
In the fall, you can bring your basil plant back inside, keep it in a bright, sunny spot, and overwinter it to grow the following summer.
How to Propagate Your Basil Plant
Basil can be grown indoors from seed; however, your rate of success will increase with some specialized equipment. Since basil seeds germinate best when soil temperature is around 80 degrees, a seed starting mat can be used to create these conditions if your space is too cool. This electric mat sits under the seed tray and gently warms the soil to the proper temperature. They also need plenty of light, such as from a bright, sunny, south-facing window or a grow light.
To propagate basil from seed, you’ll need seed trays, seed starting soil mix, basil seeds, a clean spray bottle filled with water, and optional grow light.
Step 1: Fill the seed trays to a half-inch from the top with seed starting mix and water the soil to moisten it.
Step 2: Make a tiny divot a quarter-inch deep in the center of each cell in the seed tray with your finger. Sprinkle a couple of basil seeds into each divot. Gently cover the seeds with soil.
Step 3: Carefully spritz each cell with water to moisten the seeds and soil. If your seed tray includes a clear plastic cover, place the cover over the tray to hold in moisture.
Step 4: Place the tray in a warm spot (between 70 and 80 degrees) with bright, full sunlight (or use a grow light).
Step 5: Check the seed tray daily to make sure that the soil is moist and spritz cells with the spray bottle as needed. Seeds should germinate in five to 14 days depending on the soil temperature. Once you see your first seedling sprout, remove the dome, if using.
Step 6: Once seedlings have two or three sets of leaves, you can transplant them into small pots and care for them as usual.