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How to Grow Basil Indoors- A Beginners Guide

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A Beginners Guide on How to Grow Basil Indoors

If you love Italian or Mediterranean cooking then you’ll be familiar with the delicious fragrance and taste of basil.

Basil (Ocimum Basilicum) and tomato would have to be one of the great food combinations, working beautifully together in Italian tomato sauces, pesto and summer salads.

Being a native of the Mediterranean, basil loves warm, sunny conditions and is generally grown as an annual offering a summer time harvest.  

Indoors, basil grows well in pots and enjoys the escape from outdoor frosts and chills that can lead to its demise.

This guide on how to grow basil indoors, will give you the best chance of success with this wonderful herb, even if you’re brand new to indoor gardening.

Just follow our easy basil care instructions for growing and maintaining basil indoors, and you shouldn’t have too many problems.

We’ve even thrown in a basil pesto recipe as well as some ways to enjoy the benefits of basil beyond its use as a cooking ingredient. So, let’s get started!

Growing Basil Indoors

Light

Basil loves plenty of direct sunlight so try to give your plant 6 – 8 hours of bright light each day, especially during the growing season.

If this is not possible, artificial light from an LED grow light or a fluorescent light can help.

Temperature

As mentioned early, basil originates from the Mediterranean where the summers are very warm and the winters quite mild.

Therefore, with basil, it’s really a matter of the warmer the better. If you are growing basil indoors from seed, you’ll have better results with germination if the soil temperature is 70F or 21C or above.

This is why basil is often grown in greenhouses outdoors or placed on south facing window sills indoors, to maximize temperatures.

During winter, try to keep your plant as warm as possible by avoiding draughts and direct contact with window sills.

Watering Basil Indoors

During the growth season of late spring to late summer, it’s important to keep the soil moist.

This is especially so for potted basil placed in direct sunlight. You may have to water every other day, or as required.

Although there are plenty of gadgets available for testing soil moisture levels, I still feel the best method is the old finger in the soil method.

If the top half inch of soil is dry, then it’s time to give your plant a drink.

Never over water basil as this can lead to root rot, a terminal condition for most indoor plants.

During winter, you can pull watering right back as the plant is dormant, needing only minimal moisture.

Don’t let the soil dry out though, as this may occur due to indoor heating.

Soil Mix

Any good quality, well-draining soil mix will be fine for basil.

Feeding

Because basil is a very leafy plant, it requires plenty of nitrogen. Once a week, use a liquid fertilizer high in nitrogen when watering your plant during the warmer months.

Seaweed based feeds are also ideal as they are rich in nutrients.

Tomato plant feeds work well too with basil but don’t worry if all you have is a general-purpose vegetable fertilizer, that will work as well.

There’s no need to fertilize your basil during the colder months as the plant will be dormant and in little need of nutrients.

Avoid fertilizers rich in phosphorous (P) or potassium (K) as they will encourage unwanted flower growth to the detriment of optimal leaf production.

How to Grow Basil Indoors from Seed

Begin growing your basil from seed, six weeks before the last frost. To find the average last frost date in your area, go to https://www.almanac.com/gardening/frostdates

Sow a fresh pot of basil every couple of weeks to give you a steady supply over summer.

Once your basil plant reaches six to eight inches in height, begin to harvest the leaves. When temperatures reach around 80F (26C), leave will grow very quickly.

Harvest regularly during the growing season to encourage further growth.

Pruning Basil

When your basil seedlings develop six sets of leaves, prune the plant back to just above the second set to encourage bushy growth.

Every time a branch gets a set of six to eight leaves, prune the branch back to the first set of leaves.

Around six weeks later, pinch off the center shoot to prevent the plant blooming too early.

If more flowers appear, pinch them off so the plant can concentrate its energies on producing the leaves you are after, not flowers.

Types of Basil

Basil comes in a wide range of varieties, especially when you are looking to grow from seed. Retail plant centers may be limited in the basil varieties they offer, when it comes to established plants.

Here’s a few of the more popular types of basil;

(Sweet) Thai Basil

Seedlings of Thai basil in a pot,

Ocimum Basilicam (v.Thyrsiflora) or Thai basil is part of the mint family having a sweet, spicy flavor, a bit like licorice or anise mixed with cloves.

Also known as ‘Sweet Thai’ basil the plant will grow to a height of twelve to eighteen inches (thirty to forty-six centimeters) with green leaves one to two inches (two to five centimetres), and purple stems and flowers.

Holy Basil

Holy Basil in a Cup

Octimum Tenuiflorum or holy basil is also known as Tulsi or sacred basil, and is a revered plant amongst people of the Hindu religion, in its native home of India.

It’s considered to possess powerful health and beauty properties and is used to make herbal tea for boosting the immune system.

Holy basil only grows to fourteen inches in height and has purple and green mottled leaves.

Purple Basil

Young Purple Basil in a pot

Ocimum Basilicum (v.Purpurascens) is also known as dark opal basil and is completely purple in color. Purple basil can grow up to twenty inches in height and adds a lovely splash of color to a salad or basil pesto.

Lemon Basil

A close up photo of lemon basil

Ocimum Citriodorum or lemon basil can grow up to twenty- four inches in height and has light green leaves and white flowers.

Having a subtle lemon bouquet and flavor, lemon basil makes a great addition to a salad with fish or basis for a refreshing iced tea.

Basil for Health & Beauty

Health

Basil is an important part of the Mediterranean diet, a diet that is believed to be responsible for the longevity and general well- being of those who live in that part of the world.

When eaten regularly, basil is a great source of many important vitamins and minerals, such as Vitamin C, iron, calcium and potassium.

Herbalists use basil as an anti- inflammatory to help relieve the pain of arthritis, the symptoms of cold and flu, respiratory problems and increase blood flow. 

Beauty

Basil has been used as a beauty agent for thousands of years due to its anti ageing and healing benefits.

Being high in anti-oxidants, basil can help keep your skin looking younger for longer.

The health benefits of basil can be enjoyed not only when the plant is eaten, but also when applied externally to the face.

Cool some basil tea and use as a toner or combine with some egg whites and sea salt to create a face mask to reduce the appearance of fine lines and wrinkles.

Place some wet basil leaves under your eyes to help remove the appearance of dark circles.

Basil’s antiseptic properties can help reduce acne, redness, black heads and spots.

Trouble Shooting- Common Basil Care Issues

When grown indoors, potted basil plants are generally free from pests and disease, certainly when compared with those grown outdoors.

Here are some of the most common basil care issues;

Problem: pale green or yellowing leaves

Cause:  lack of nitrogen

Solution: Feed with a liquid fertilizer high in nitrogen

Problem: leaves turning yellow & drooping

Cause: aphids or mealy bugs

Solution: Shower the plant to remove the insects or use insecticidal soap

Problem: Stunted growth

Cause: Too little sunlight / warmth

Solution: Place the plant where it will be bright and warm, with the basil exposed to direct sunlight for 6-8 hours

Problem: Stunted growth, wilting, leaf drop, yellow leaves, brown spots on stems, twisted stems

Cause: Fusarium Wilt

Solution: There is no cure for this bacterial disease so plants must be removed and destroyed. Sterilize the pot and use fresh soil from a different source.

Basil Pesto Recipe

Home made basil pesto in a jar surrounded by pine nuts

Basil pesto is a very popular Italian food, usually made using sweet basil, but can be equally enjoyed using any of the basil types listed above.

Basil pesto does tend to darken when exposed to the air, so store in an airtight container to prolong usage.

Ingredients:

  • 2 cups of fresh basil leaves (packed)
  • 1/3 cup pine nuts (alternatively use walnuts or almonds)
  • ½ cup extra virgin olive oil
  • ½ cup Parmesan, Reggiano or Romano cheese (grated)
  • 3 clove of garlic (minced)
  • 1/4 teaspoon salt
  • 1/4 teaspoon ground black pepper

  Method:

  • Place the basil and pine nuts into your food processor and pulse a few times to chop
  • Add the garlic and cheese, pulse a few more times, then scrape down the sides of the food processor
  • With the food processor running, slowly add the olive oil, which helps prevent separation occurring. Stop occasionally to scrape down the sides
  • Add the salt and pepper to taste and stir well

I do hope that you’ve enjoyed this guide on how to grow basil indoors. If so, why not pin it on Pinterest!

How to Grow Herbs Indoors – The Series

Introduction: how-to-grow-herbs-indoors

Basil: how-to-grow-basil-indoors-a-beginners-guide

Mint:  how-to grow-mint-indoors

Cilantro: how-to-grow-cilantro-indoors

Parsley: growing-parsley-indoors

Rosemary: how-to grow-rosemary-indoors

Sage: growing-sage-indoors

Thyme: growing-thyme-indoors

 

Christine Mattner

What started out as purely a desire to keep my indoor plants alive has turned into a full-blown passion for sharing what I have learned over the years about selecting, growing and caring for indoor plants with those who may be new to the wonderful world of houseplants.

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