This article shares everything you need to know about how to grow basil. It includes how to grow basil from seed, plus tips for pruning, harvesting, and using basil. I’ve also included tips for growing basil in containers, growing basil indoors, and how to grow basil in Arizona.
One of the most popular herbs to grow, basil is a warm-weather fragrant herb in the mint family, whose flowers attract native bees. It is also a favorite culinary herb, treasured for its color and flavor. In all but the warmest regions (zone 10 and higher), basil is grown as an annual and will grow until the first frost.
10 Tips For Growing Basil
1. Basil is a warm-season herb
- Start seeds indoors 2-4 weeks before planting basil outside.
- Plant seeds outside about ¼ inch deep and 10-12 inches apart when nighttime temperatures are above 70℉.
- Don’t rush putting transplants outside; basil prefers warm air and soil.
- Plant transplants at the depth of the container about 12-18 inches apart, depending on the variety of basil.
- Plant basil in an area that gets full sun.
2. Don’t let basil dry out
Basil likes well-draining soil. It’s important to water basil regularly so it doesn’t dry out and become bitter. Mulching plants also helps to preserve moisture. During hot weather and dry periods, water basil deeply and regularly.
4. Learn how to prune basil for larger yields
- When basil is about 6” tall, cut the middle stem down to just above the second set of leaves. 2 new stems will grow back in the middle stem’s place.
- Cutting back at this early stage of development encourages the plant to branch and produce additional leaves.
- As the plant grows, continue the practice of cutting back the branches to the second set of leaves.
- Remove the center shoot of basil to discourage blooming.
- To encourage new growth, cut back flowers as they appear.
5. Grow tomatoes and basil together - a perfect match in the garden and on the plate
Tomatoes are excellent companion plants for basil; introduce them to each other while they are growing as well as in the kitchen. According to Carrots Love Tomatoes, “Basil helps tomatoes to overcome both insects and disease, also improving growth and flavor.” I’ve found this to be true in my own garden.
6. Harvest basil early and often
- Begin harvesting basil when plants are 6-8” tall.
- The more you harvest basil, the more it grows.
- Harvest basil regularly, even if you are not using it, to encourage branching and production.
- Basil leaves lose moisture throughout the day. Harvest basil in the morning for the best-tasting leaves.
7. Enjoy the fresh flavor of basil in many ways
- Use only basil leaves, not the stem, in cooking.
- Add basil at the end of cooking time to help retain fresh color and flavor.
- Freeze or dry basil to preserve the harvest – freezing preserves the most flavor.
- Use a large harvest of basil to make pesto.
- Freeze individual leaves together in a freezer bag, and pull out individual leaves as needed.
- These herb scissors are my favorite way to cut up fresh basil. So easy!
- Purée washed basil in the blender and add just enough olive oil or water to make it pourable. Then pour into ice cube trays and freeze. It’s so convenient to pop one or two cubes into soups and pasta.
8. How to grow basil in Arizona
- Start seeds indoors: January 15 – April
- Plant seeds outside: February 15 – May
- Plant transplants outside: March – May
- In the hot summers of Arizona, basil does best with some afternoon shade.
- Smaller-leaved varieties grow best in the low desert of Arizona. Be sure to provide afternoon shade for larger-leaved varieties such as Genovese.
- Mrs. Burns lemon basil, Siam Queen, and African Blue all thrive in Arizona’s heat.
- Mulching plants helps retain moisture and keeps weeds down.
9. How to grow basil in containers
- Basil needs well-draining soil. Always use a good potting soil in the containers, not garden soil.
- Don’t overcrowd plants. Adequate air-flow around basil plants is important to prevent fungus. Allow at least 6-8” between plants; 12” is even better.
- Don’t let containers dry out. Regular watering is key for the best-tasting basil. To see if the container needs water, use a moisture meter or stick a finger into the soil. If the top inch or two of soil is dry, water the container.
- Feed basil in containers regularly. Nutrients are leeched out the drain hole in containers, and basil grown in containers will benefit from monthly or bi-weekly feedings from compost or organic fertilizer.
10. How to grow basil indoors
To successfully grow basil indoors, provide the light and warmth it would receive if it were growing outside. A sunny south-facing window may be all you need, but in most cases, additional light and warmth will be required to successfully grow basil indoors.
- Avoid drafty locations – 80℉ is the minimum temperature basil needs to thrive.
- If you are growing basil near a window, rotate the plant each time you water to keep the growth even on all sides.
- When using a grow light, set a timer to run the light for 12 hours with the lights about 2-4″ away from the plant.
- If seedlings are leggy, they need more light (change location or put grow lights closer to leaves). Bleached out spots on the leaves indicate the lights are too close to the seedlings.
- Thin basil to at least 6” apart to provide adequate airflow and discourage fungus.
- Begin harvesting leaves as soon as the plant is over 4” tall.