If you’re planning on starting a sustainable herb garden soon, basil is a must-have. Its ability to flourish both in the garden and the kitchen makes it a popular choice for beginners and pros alike.
Basil, or Ocimum basilicum, is one of the easiest garden herbs to grow. All you need to start growing is a warm, sunny season, and some well-draining soil. A relative of the mint family, basil is used around the world in recipes for tomato sauce, pesto, cooking oils, teas, and more.
Although basil readily thrives in a variety of conditions, it’s not exactly a “set and forget” kind of plant. This article will tell you how to grow and maintain basil, including pruning, fertilizing, and managing common pests.
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What Is Basil?
Ocimum basilicum, commonly known as basil, is a member of the Lamiaceae family (mint). It is native to the South Pacific islands and parts of southern Asia. In the United States, basil is only perennial in USDA plant hardiness zones 10 and 11.
Basil is a tender annual, which means that it won’t tolerate freezing temperatures. By contrast, hardy annuals can be planted in early spring, since they can handle colder weather and soil temperatures.
Basil is a flavorful, aromatic herb and its leaves can be eaten fresh or dried. It also comes in many varieties, making it a versatile ingredient that can be tailored to many dishes. The most commonly grown basil types in the US include sweet basil, cinnamon basil, lemon basil, purple basil, and Thai basil.
Planting Basil
Although basil isn’t particularly picky about its growing conditions, certain factors will enhance your success greatly if you can provide them. Here are some of the basics:
Soil type
Like most vegetables, basil grows best in soil with a pH of between 6.0 – 6.5. If you’re not sure what your soil’s pH level is, you can get a testing kit at your local garden center.
If your soil falls significantly out of the recommended pH range, you can amend it with sulfur or limestone. Sulfur will lower raise pH levels in soil, while limestone will increase pH. If possible, you should amend your soil several months before planting your basil or other vegetables, so that it has time to adjust.
Another soil characteristic to be mindful of is composition. Basil does best in loamy soil that drains efficiently. If the quality of your garden soil is questionable, you could keep your herbs in raised beds. This allows you to easily control the growing conditions and make adjustments as needed.
Light
Basil does best in areas that get at least 6-8 hours of sun per day, so place it in the sunniest location in your garden. If you’re growing indoors, place it in an unobstructed warm southern-facing window if possible.
If you don’t get enough natural light indoors, consider supplementing with a grow light to give it the best chance of success.
Time of year
Since it’s a tender annual, basil plants love warm temperatures. Especially if starting from seed, you should wait until the daytime temperatures are consistently in the 70s (Fahrenheit), and nighttime temperatures don’t go below 50 degrees Fahrenheit.
At the very least, you should be sure that the danger of frost has passed before you plant your basil. If there is an unseasonably cold day, you can offer your plants extra warmth by covering them up, or bringing them inside if they are kept in pots.
Many gardeners like to start their basil indoors and wait until warmer weather sets in to place them in the garden. If you’d like to try this, you can get your seeds started about 6 weeks before the estimated last frost of the season.
If you grow your herbs inside, you can technically plant basil at any time of the year. You will need to make some adjustments based on the season, however.
If you’re starting seeds or transplanting in the winter, for instance, your plants might need more light and warmth than what is available to them, depending on how warm you keep your home. You can work around this by using a heat mat designed for starting seeds, and with grow lights.
Watering Basil
The amount of water basil needs depends on its life stage, the climate in your area, and how you’re growing it. Climate matters because when an area is hot and dry, moisture evaporates more quickly, and plants need more frequent watering. Conversely, plants in cool, wet areas won’t need to be watered as often.
Like most herbs and vegetables, when you’re growing basil from seed, it will need to be kept moist in the early stages of growth. Moisture and sunlight are the main elements that trigger seeds to germinate. Soil that contains seeds and immature basil should feel like a sponge that has been rung out – damp, but not dripping.
When your basil is well-established and has mature leaves, you can decrease the frequency of watering. Outdoors, you can expect your basil to need a nice, thorough soak every 7-10 days.
Monitor the soil at least every other day to be sure, though. If you stick your finger into the soil and it feels wet, hold off and check it again the next day. Water your plants when the soil is dry no more than an inch below the surface.
Fertilizing Basil
Basil does not have significant fertilizing needs. In fact, heavy feeding can have a negative effect on the herb. Over-fertilizing basil can cause the plant to grow too quickly, diminishing the flavor of the leaves.
You only need to fertilize your basil plants once or twice per growing season. For typical conditions, any commercial 5-10-5 fertilizer should be sufficient to provide all of the nutrients your basil needs.
Pruning Basil
Routine pruning throughout the growing season is a necessary part of basil care and maintaining healthy, active growth. If left unpruned, your plant will yield less foliage over time, and the leaves will be less flavorful.
Here are some of the basics to help you get started:
- First trim: Once your seedlings grow their first 6 leaves, trim the top leaves so that only the first 2 sets of leaves remain. This will trigger your basil to start branching out and producing more leaves. The new leaves will be more flavorful as a result.
- Regular pruning: You’ll perform a similar process for each new branch – once it grows 6 leaves, prune them back to the first set of leaves.
- Prevent flowering: Unless you’re planning on collecting seeds, pinch off any flower buds as soon as you notice them. Basil that is left to flower and seed will turn woody, produce less foliage, and become bitter-tasting.
Basil Propagation
Basil can be propagated by seeds, division, or stem cuttings. Dividing your basil is the easiest way to propagate.
To divide a plant, remove it from the soil and gently separate the root ball in half. You can divide each half again providing that there are enough healthy shoots in each section.
Stem cuttings are another easy way to multiply your basil, or give some to a friend. To do this, cut a stem that is at least 4 inches long just below a leaf node. Remove the bottom set of leaves, as this is where new roots will emerge.
You can root stem cuttings either in water or potting mix. Some growers like to root in water since you can monitor the process of roots forming in a clear glass.
The catch is that it can be tricky to successfully transfer the cutting from water to soil once the roots are long enough. Either method will work if done properly – it depends on your preferences.
Basil Diseases & Pests
Although basil isn’t particularly susceptible to any major pests or diseases, there are a few issues to watch out for:
Japanese Beetles: These green and brown insects will chew holes in your foliage. To get rid of them, you can remove each bug you see and drop them in a bucket of soapy water.
Aphids: These tiny green pests damage their host plant by sucking the juice from its leaves and stems, resulting in yellowing foliage and reduced growth. Spray the leaves thoroughly with an insecticidal soap to eradicate them.
Basil Downy Mildew: This disease is caused by a water mold that infects plants starting on the lower leaves, and spreads from plant to plant fairly quickly. Downy mildew is characterized by fluffy spores that grow on the underside of the foliage. Any plant you notice this on must be removed and disposed of immediately.
Conclusion
Growing your own herbs can be a very rewarding (and delicious) project. It might be challenging at first to master your basil’s care routine, but even the most experienced gardeners go through some trials and errors when starting new plants.
I hope you found this article helpful. If so, please share it with someone who can use the information.
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About the author:
Kathryn is a plant enthusiast and freelance content writer who specializes in home and garden topics. Based in New York, you can get in touch with Kathryn at https://kathrynflegal.journoportfolio.com/.
