How to Grow Basil – Comprehensive Guide

Failing at growing basil plants? We'll show you how to take care of yours properly so it can continue to thrive.

If ever an herb said summer, it’s basil.  Ocimum basilicum – is a member of the mint family and is native to India. It is an easy herb to grow for beginners and old-timers alike.

This woody, branching plant that is a warm-weather annual can easily be found at garden centers in the spring and summer, or even in the produce section at your grocery store. This is probably because freshly picked leaves have such wonderful fragrance and taste and is used in so many different cuisines worldwide including the beloved pesto!

It’s nice to have fresh basil available year round, whether you grow this herb in your garden or on your windowsill. 

Common Varieties

There are many different varieties, and each type brings a different flavor to the dishes you create.  Here are some of the most popular:

  • Sweet basil reaches 24 to 30 inches in height and gets 18 inches wide, so give it plenty of space in your garden. If you are new to growing basil, this is the first one to try; it’s the herb known around the world.  It’s very flavorful and aromatic. 
  • Spicy globe basil gets only 6 to 12 inches high and makes a tidy sphere of spicy green leaves – perfect for use in containers.  It’s a little spicier than the sweet variety, but can be used in the same ways.
  • Thai basil grows 12 to 24 inches tall and wide and has a licorice flavor, stronger than the sweet variety. It is an attractive plant with purple stems, and it is a staple of Thai cuisine.
  • Lemon basil, also known as the Lao variety, grows 8 to 20 inches tall.  This hybrid has a citrusy scent and a lemon flavor and is a favorite in Indonesian cooking.
  • Cinnamon basil gets big – 18 to 30 inches high and 12 to 18 inches wide. It has a smaller leaf than the sweet variety with cinnamon-colored stems.  It has a spicy cinnamon flavor and is popular in Italian and Asian cuisines.
  • Genovese basil grows 16 to 18 inches high and 12 to 16 inches wide. This is the classic Italian variety and is very fragrant with dark green leaves that make the fantastic pesto. 
  • Purple basil gets 18 to 24 inches tall.  This colorful herb has a spicy clove-like taste. When grown in a container with other herbs or with flowers, it creates a gorgeous summer combination. It’s a dual-use plant, providing both beauty and flavor.
Multiple basil types grow together with proper fertilization and water
Purple and Genovese Plants Growing Together

Planting Tips

You can grow basil indoors or outside, and either in the garden or containers.  Grow it in full sun in healthy, well-drained garden soil.  It prefers a soil pH between 6 and 7.  As a true summer annual, it hates temperatures below 55°F, so make sure the weather and the soil have warmed up before planting it outside. 

Growing Outdoors

Grow them outdoors in the vegetable garden, in a dedicated herb garden, or in containers, such as trough planters.  Consider planting it with other herbs and vegetables that require the same growing conditions – full sun and moist, well-drained soil.

Growing Indoors

You can also grow them indoors on a sunny windowsill or under grow lights so that you can have basil year round.  Even one plant will give you lots of tasty leaves.

Growing from Seed

Start seeds indoors about 6 to 8 weeks before the last frost date in your area.

  • Use a good quality seed starting mix. 
  • Moisten the soil and place 2 or 3 seeds in each pot. 
  • Cover the seeds lightly with soil and water gently.  A spray bottle of water works great for this. Cover the soil with plastic wrap to help hold in the moisture.  The seeds need to be constantly kept moist to germinate. 
  • Seedlings will sprout in 5 to 7 days. Remove the plastic wrap and be sure to keep the soil most as the plants grow.

Basil needs soil temperatures to be at 70°F to germinate, so don’t plant seeds in the garden too early.  We don’t recommend starting from seed in the ground below zone 6, as the soil will be too cold for the seeds to germinate until summer.  And it will be weeks until your plants are mature enough for harvesting. 

So why wait?  Buy a few plants at the nursery and you can start harvesting and using fresh leaves in just a few weeks.

Germination Time

It usually takes seeds about 7 to 10 days to germinate after you plant it. After that, the first set of true leaves should develop 2 to 3 weeks later. And finally, the another 2 to 3 weeks later, the plant should be about 6 inches tall and should be ready for its first harvest.

A basal plant ready to be harvested that is growing outdoors

Planting in the Garden

If you will be growing it in your garden, plant your basil 2 weeks after the last spring frost. It cannot tolerate temperatures below 55°F, so wait until warm weather has arrived to plant. Give it enough room to grow and develop, usually 12 to 18 inches apart. Grow in nutrient-rich, well-drained soil with a pH of 6.0 to 7.0.

Steps to Planting

  1. Mix a little compost into your garden soil and rake smooth.
  2. Space your plants twelve to eighteen inches apart, closer if you are planting smaller varieties.
  3. Make sure the plants are set properly in the planting holes – when you fill in the soil, the tops of the root balls should be just slightly covered.
  4. Pat the soil so it is firm, and water well.

When you plant in containers, the same steps apply.  Just be sure to use good quality potting soil.

Companion Planting

Some plants, when planted together, provide benefits to each other – increased yields, improved health and protection from pests, as well as an invitation to beneficial insects and pollinators.  Gardeners have been using these planting techniques for centuries, and while we make no guarantees, companion planting is certainly something to try. 

Basil is a good companion plant to lots of garden plants.  It has natural pest repellent properties and many gardeners say planting it with tomatoes makes the tomatoes taste better.

Companion Plants

  • It grows well with oregano, chives, and chamomile.  But keep rue and sage away.
  • Basil and tomato plants compliment each other in the garden and in cooking too.  It also grows well with potatoes, beets, cabbage, beans, asparagus, eggplant, chili, and bell peppers.
  • When you plant it with marigolds (another pest repellant), you can really keep the bugs at bay.
Basil plant growing with its companion plants including tomato and lettuce
Basil growing with lettuce and tomatoes.

Caring Guide

As we’ve said, basil grows best in full sun in well-draining soil, but keep in mind that hot midday sun can cause sunscald or scorch and the leaves will turn brown.  Keeping your plant well-watered can help.  Remember that it needs a little more water than some other herbs.

Once these basic needs are met, you will find that it is very easy to grow.  Just follow the tips below.


Unlike some other herbs, basil likes constant, slightly moist soil, so don’t let your plants dry out.  Water early in the day and avoid getting the leaves wet.  If leaves are wet for too long, there is a chance that black spot or other fungal diseases can take hold.


Pruning your plants will encourage them to branch and produce lots of new leaves.  Pinch the growing tips, too, because the more you pinch, the more tasty, tender leaves you’ll get.

When basil flowers, the plant starts producing smaller and fewer leaves.  It is putting its energy into making seeds.  By deadheading, you can prevent the plant from going to seed.  So keep your plant in a vegetative state by pinching.  And if your plant does flower, pinch off the flowers and use them as a garnish.

A person is seen pruning a basil plant from a flowering bud.

Pests and Diseases

With good cultural practices, gardeners can avoid disease problems.  As mentioned above, keeping water off the leaves helps prevent black spot, mold, downy mildew, and other fungal diseases.  Good airflow around the plants is also helpful.

Sun scorch can occur when it gets too much midday sun.  Leaves with brown edges tell you a plant has sun scorch.

Japanese beetles, slugs, and snails will find your plant tasty and leave holes in the leaves. You can simply pick these pests off if you’re not too squeamish.  Basil is occasionally bothered by aphids and spider mites.  These pests can be dislodged with a strong spray from a garden hose.  Or use a pesticide labeled as safe for food use.


Harvesting is very easy.  Simply pinch off the leaves from the stems.  Harvest in the early morning, when the flavor is at its peak.

Basil that has been grown indoors is ready to be harvested
Indoor growing in a container

Drying and Storing Basil

Basil can lose its fragrance when dried, but it still has its uses in the kitchen – in pizza sauces, marinades, and teas.

  • After you harvest, rinse the leaves and make sure to remove any that are brown, spotted, or moldy – you want fresh, green leaves.
  •  Lay out the leaves in a single layer on a towel and pat dry.
  • Allow them to sit undisturbed until they dry completely.  This may take 3 to 4 weeks.
  • When the leaves are dry, gently place them in a glass container.  Try not to break or crush the leaves as this releases the oils, which give it its wonderful aroma.
  • Tightly seal the container and store it in a cool, dry place.
  • Only crush the dried leaves when you use it.
  • When it loses its fragrance completely, it’s time to replace with another fresh harvest.

This method works with any variety.

A Couple of Things to Try

Basil is an herb with uses beyond the kitchen.  Here are a few ideas to get you exploring recipes, herbal remedies, and more!

  • Boil 7 to 10 leaves in a cup of water for about 10 minutes.  Let cool, then strain the liquid and use it as a skin toner.  It’s said this topical application can help soothe acne.
  • Freeze leaves in an ice cube tray for a festive addition to a summer drink.
  • Make pesto from basil, garlic,  pine nuts, and oil.  A quick internet search will bring up lots of tasty recipes.
  • Toss tomatoes, mozzarella, and basil with a little high-quality olive oil to create a sensational summer salad.
  • Try a Thai mojito!  Muddle a few fresh leaves instead of mint when you make this classic cocktail.
  • Make an all-purpose household cleaner by soaking basil and orange or lemon peels in vinegar for several days.  Strain, and fill a spray bottle half full with the vinegar and add water. 
Alaine Connolly
Alaine has been working way too hard in horticulture since 1992, beautifying golf courses, resorts, and hotels. She is a part time landscape designer who works full time caring for a 28,000 square foot public garden. At home, she maintains her own 400 square feet plot. Alaine lives in northern Illinois - zone 5b.
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