Growing Thai Basil in Pots

Thai basil, with its distinct licorice-anise flavor, is a beloved herb in many Asian cuisines. But did you know you can easily grow this tropical plant at home? With the right care and conditions, you’ll have an abundant harvest of flavorful Thai basil from pots on your patio, balcony, or windowsill.

In this comprehensive guide, we’ll walk through everything you need to know to successfully grow potted Thai basil plants. You’ll learn insider tips on choosing the optimal pot and soil, how much sun and water to provide, the best planting and care methods, and how to troubleshoot any issues along the way.

Selecting the Perfect Pot for Thai Basil

The first step in growing Thai basil in containers is choosing an appropriate pot. This tropical herb prefers warm temperatures and humid conditions. Picking the right pot will help recreate its ideal environment. Here are the key factors to consider:

Pot Size

Opt for a pot that is at least 12 inches deep with ample room for root development. Thai basil has an extensive root system and requires more space than you might expect. A cramped container will restrict growth.

Aim for a 5-gallon pot as the minimum size for a full-grown Thai basil plant. For multiple plants, use at least a 10-inch wide container and allow 8-12 inches between plants. Alternatively, you can plant 3-4 Thai basil plants together in a 20-inch wide planter.

Drainage Holes

Ensure your pot has several drainage holes at the bottom. Thai basil hates wet roots and is prone to root rot. Drainage holes allow excess moisture to freely escape, preventing waterlogging.

You can add pebbles or gravel at the base of the pot to further improve drainage. Place a saucer under the pot to catch dripping water.


Thick, sturdy containers made of terra-cotta, plastic, or ceramic work best. Avoid thin pots that overheat in the sun. Dark-colored pots absorb and retain more warmth which benefits the heat-loving basil.

Terra-cotta is an excellent choice as it’s breathable, releasing moisture to create the humid microclimate basil enjoys. Glazed ceramic and plastic pots also work well.

Creating Rich, Nutrient-Packed Soil

The second pillar of success with container Thai basil is getting the soil right. Basil requires nutrient-rich soil that drains well. Here’s how to create an ideal potting mix.

Aim for Loose, Loamy Soil

Thai basil thrives in loose, crumbly soil that allows air circulation to the roots. Soil that is too dense or compact will suffocate roots and encourage rot.

To lighten heavy garden soil, mix in equal parts of organic material like compost, peat moss, or coco coir. Perlite or vermiculite can also be added to improve drainage.

A general houseplant potting mix amended with extra perlite works perfectly for basil. Or you can create your own customized soil blend.

Pack in Organic Nutrients

Enrich the potting mix with slow-release organic fertilizer like compost, worm castings, bone meal, kelp meal, or bat guano. This provides a steady feeding of nutrients to fuel growth.

When preparing the soil, work 1-2 tablespoons of granular organic fertilizer per gallon of soil into the mix. Reapply this 2-3 times during the growing season.

Liquid organic fertilizers like fish emulsion or compost tea can also be used to give container basil an occasional nutrient boost.

Monitor the pH

Test the potting mix pH and amend if needed to fall in the 6.0 to 7.0 range. Basil prefers a slightly acidic soil. Add sulfur or peat moss to lower pH. Lime can be used to raise pH if too acidic.

With rich, loose, well-draining potting soil, your Thai basil will thrive! Proper nutrients encourage vigorous plants with a bounty of harvestable leaves.

Let the Sun Shine on Your Thai Basil

As a tropical plant native to Southeast Asia, Thai basil relishes heat and sunlight. Giving your potted basil full sun is key to robust growth. Here are sunlight specifics:

Place Outdoors in Full Sun

When temperatures have warmed in spring, move your Thai basil to a spot outdoors that receives at least 6-8 hours of direct sunlight per day. More sun is even better.

South or west-facing spots are ideal. Dappled shade under taller plants is also suitable, as long as the basil gets plenty of unobstructed sunlight during the day.

Supplement with Grow Lights

If growing indoors year-round, invest in full-spectrum LED grow lights. Position the basil 2-4 inches below grow lights and run them 12-16 hours per day. This mimics outdoor light levels.

Rotate the pot weekly so all sides of the plant receive equal light exposure. Without enough intensity, you’ll end up with weak, leggy basil.

Watch for Leggy Growth

If your basil is growing tall with sparse leaves, it’s not getting sufficient sunlight. “Leggy” growth results when a plant stretches toward a light source.

Increase light immediately by moving the pot or adding supplemental lighting to prevent further legginess. Prune back any elongated stems.

Maximize sunlight for your Thai basil, and it will reward you with vigorous, bushy plants and non-stop leaf production. Light is the fuel behind this sun-worshipping herb.

Watering Wisely: The Art of Satisfying Basil’s Thirst

Providing the right amount of water may be the most important factor for thriving container basil. Underwatering causes wilt and lower yields. Overwatering leads to root rot and death. Proper watering encourages healthy, flavorful plants. Follow these guidelines:

Water When the Soil Surface is Dry

Basil needs moisture, but its roots quickly suffer if soil is kept too wet. Only water when the top 1-2 inches of soil becomes dry. Probe with your finger to check moisture levels before watering.

In hot weather, this may mean watering daily. In cooler conditions, basil may need water only every 3-4 days. Adjust as needed.

Water Thoroughly Until It Drains

When watering, apply enough so that excess moisture trickles from the bottom drainage holes. This ensures water penetrates the entire root zone.

Avoid shallow watering that only dampens the top of the soil. Err on the side of overwatering and let the excess drain out.

Empty Excess Water from Saucers

If the pot sits in a saucer, empty excess water after moistening so the pot is not left sitting in water. Allow the saucer to fully dry between waterings.

Leaving pots to sit in water is a recipe for disaster with Thai basil. Its roots will start to rot within days.

Adjust Watering Frequency

As plants grow, they require more frequent watering. Mature potted basil may need water twice a day in hot, dry weather.

Check soil daily and adapt your watering routine based on pot size, weather, and growth stage. Basil immediately shows signs of distress if too dry.

Use Rain or Distilled Water

If possible, use rainwater or distilled water for irrigating container basil. Tap water with salts, chlorine, and fluoride can accumulate and burn basil’s sensitive leaf tips.

With the right moisture balance, your Thai basil will produce an abundance of aromatic leaves all season long. Learn its needs and water accordingly!

Grow Happy Basil in Warm Conditions

Warmth is essential for thriving Thai basil. Originating in tropical environments, basil grows best in temperatures between 70-85°F and appreciates humidity. With a few simple strategies, you can recreate its ideal climate:

Grow as an Annual in Temperate Climates

In regions with cold winters, grow Thai basil outdoors as an annual. Transplant seedlings after all danger of frost. Overwintering indoors is challenging.

Before the first fall frost, harvest all remaining leaves. Take cuttings to try overwintering indoors under grow lights.

Move Indoors if Temperatures Drop

When growing in containers, immediately move pots back indoors or under shelter if temperatures fall below 60°F, even temporarily.

Chilling damage causes basil leaves to turn black. Just a single night of cold can set your plant back weeks.

Warm Indoor Growing Areas

To grow Thai basil as a houseplant, place containers in the warmest, sunniest room indoors. Bright southern windows are perfect. Maintain temperatures above 70°F.

Avoid drafty areas. Consider using a heating mat to maintain warm soil. The microclimate right around the plant is most important.

Increase Humidity

Thai basil appreciates 40-60% relative humidity. Place pots on pebble trays with water or use a humidifier nearby. Misting leaves also increases humidity temporarily.

If the air is too dry, the leaf edges of basil can brown and curl. Monitor conditions and make adjustments to prevent this.

Check if Rootbound

If your basil seems to wilt easily, check if the pot is rootbound. When the roots fill the container, the plant struggles to take up moisture.

Gently slide the plant from the pot to inspect. If the roots are circling densely along the edges, it needs more space. Transplant into a larger container.

With warm soil and air, enough humidity, and ample pot size, your Thai basil will thrive! Keep a close eye on all these environmental factors.

Mastering Maintenance: Caring for Container Basil

Caring for potted Thai basil plants isn’t difficult, but does require some routine maintenance. Follow these tips to keep your basil healthy and productive all season long:

Pinch Off Flowers

Once flower buds appear, immediately pinch them off. This prevents the plant from bolting and going to seed.

Removing flowers signals the plant to keep focusing energy on leaf growth. For harvestable foliage, you want as little flowering as possible.

Prune Leggy Stems

Check for stems that become overly long and leggy. Prune these back by one-third to one-half of their length using clean scissors or shears.

Removing leggy stems redirects growth lower down, creating a fuller, bushier plant. Just don’t prune more than 20% at once.

Remove Yellowing Leaves

Monitor for leaves that are turning yellow or brown. These can be selectively plucked off by hand. Removing damaged foliage improves appearance and prevent disease.

Don’t go overboard plucking leaves. But target removal of those that are clearly discolored or dying back.

Apply Organic Fertilizer

Replenish nutrients mid-season by applying organic fertilizer around the drip line. Either work granules lightly into the soil or use a compost tea.

This keeps plants actively growing. Avoid high-nitrogen chemical fertilizers that produce excessive leaf growth at the expense of flavor.

Harvest Often

Pick leaves frequently, ideally just before using them. Consistent harvesting stimulates the plant to continually produce new growth.

Remove larger leaves from the outside first. Leaving the tiny interior leaves allows the plant to photosynthesize and recover.

With smart, diligent care, your potted Thai basil will stay healthy and productive for months of enjoyment!

Troubleshooting Issues with Container Basil

Even when following best practices, you may encounter some problems while growing Thai basil. Here are solutions to a few potential issues:

Plants Wilting from Underwatering

If leaves are drooping or edges appear dried out, increase watering frequency. Basil needs consistently moist (but not wet) soil.

Feel the soil to determine if moisture is lacking. Leaves recover quickly once the plant gets a thorough soaking.

Leaves Yellowing from Overwatering

If lower leaves turn yellow and drop prematurely, reduce watering. Allow more time between waterings for soil to dry out.

Excess moisture damages roots and reduces the plant’s ability to take up nutrients, causing yellowing.

White Spots on Leaves Caused by Pests

Check the leaf undersides for small white dots. These are larvae of pests like aphids, spider mites, or thrips.

Use insecticidal soap, neem oil, or horticultural oil to treat infestations. Remove badly damaged leaves to prevent spreading.

Leaf Curling from Low Humidity

If leaf edges brown, curl, or shrivel, increase humidity around the plant through misting, pebble trays, or a humidifier.

Curling and browning is typically a result of very dry air. Basil prefers 40% humidity or higher.

Flowering Causing Decline in Foliage

If your basil is flowering and leaves seem to stop growing, pinch off all buds immediately. Fertilize after to encourage new leaf production.

Once flowering starts, the plant puts energy into seeds not leaves. Removing flowers redirects it.

With attentive care and quick troubleshooting, you can avoid most problems with container Thai basil. Just stick to its favored conditions.

Harvesting and Enjoying Your Potted Thai Basil

Once your potted Thai basil takes off, you’ll want to harvest it frequently to enjoy fresh. Here are some tips:

Harvest Basil in the Morning

For best flavor, harvest Thai basil early in the day before the sun gets hot. Warm temperatures draw out the oils, making it more pungent.

Use scissors to cut sprigs and leaves. Handle gently to avoid bruising.

Look for Anthocyanins

In Thai basil, young leaves and stems often display vivid reddish-purple coloring. This is from anthocyanin pigments.

The more anthocyanins, the more clove-like flavor. Seek out the darkest purple leaves when harvesting.

Preserve Aroma by Freezing

To freeze, lightly pack leaves and small stems in freezer bags. Or place in ice cube trays with a bit of water before freezing.

Frozen Thai basil retains more flavor than drying. Use within 4-6 months.

Make Thai Basil Pesto

One of the best ways to use an abundant harvest is to make homemade Thai basil pesto. Simply blend basil, olive oil, nuts, garlic, lime, and chili pepper.

Slather on chicken, stir into noodles, or freeze for later. It’s incredibly versatile!

Use Fresh in Thai Recipes

Of course, Thai basil shines in classic Thai dishes like curries, soups, and stir fries. Add it at the end for the strongest flavor.

Pair it with coconut milk, ginger, chilies, and lemongrass for authentic Thai cuisine.

In no time at all, you’ll have more fresh Thai basil than you know what to do with! Enjoy experimenting with this exotic, aromatic herb.

Final Tips for Growing Potted Thai Basil

Growing your own Thai basil is deeply satisfying and provides you with the freshest, most flavorful leaves possible. Follow this summary of top tips:

  • Select a 12+ inch deep container with drainage holes. Give each plant about 10 inches of space.
  • Use loose, nutrient-rich potting mix. Incorporate organic fertilizer at planting time.
  • Site in full sun. Move indoors if temperatures drop below 60°F at night.
  • Allow the soil surface to dry between waterings. Water thoroughly until it drains from the bottom.
  • Pinch off flowers to prolong leaf production. Prune leggy stems back by one-third.
  • Harvest leaves frequently by cutting sprigs. New growth will continually replace what you remove.
  • Make pesto, curries, soups, and other Thai dishes to savor the unique anise-clove flavor.

Growing potted Thai basil is easy and fun when you give it what it craves! In no time, you’ll have fresh leaves to harvest for all your culinary endeavors.