Grow More Basil: Propagate Leggy Seedlings for Abundant Harvest

Do you find your basil seedlings growing tall and spindly? Don’t worry, because you can actually turn these leggy seedlings into more basil plants. In this article, we’ll explore why leggy basil seedlings occur and how you can propagate more basil from them.

Why We Embrace Leggy Basil Seedlings

Basil is a beloved herb, especially when it comes to making pesto. And let’s face it, you need a lot of basil for pesto. Our basil seedlings often become leggy when we plant during the fall and winter months, when natural light levels are low. However, we’ve discovered a method that works wonders for us – we grow basil from seeds in starter pots and intentionally provide them with limited light. This results in well-developed yet leggy seedlings, which is exactly what we want.

You might be wondering, why would we want leggy seedlings? Well, it’s quite simple. By following this method, we consistently double the number of basil plants we have. For example, four leggy seedlings can be transformed into eight basil plants. And for us, that means more pesto!

How to Grow More Basil from Leggy Seedlings

Now, let’s dive into the step-by-step process of propagating more basil from leggy seedlings.

1. Start with Leggy Basil Seedlings

Begin with leggy basil seedlings that are at least 15 cm (6 inches) tall. Take a sharp pair of scissors and cut the stem just above where you see new leaves forming.

2. Trim the Leaves

Remove all leaves from the stem cutting, leaving only the top pair of leaves. If the cutting is shorter than 10 cm (4 inches), ensure at least one set of fully formed leaves remains.

3. Place the Cuttings in Water

Take the basil cuttings and place them in a glass or container of room temperature water. If you have enough space, use separate containers for each cutting. Remember to replace the water daily.

4. Transplant the Remaining Seedlings

Next, transplant the remaining seedlings from the starter pot into a larger pot with fertile soil that drains well. Keep the soil moist and place it in a location with good light.

5. Increase Your Basil Plants

For each leggy basil seedling, you now have two separate basil plants growing. One cutting is placed in a glass container with water, while the other seedling is in a pot with fertile soil.

6. Wait for Root Growth

After 1-4 weeks, you will start seeing fully formed white roots growing from your basil cuttings. This indicates that the cuttings are ready to be transplanted.

7. Transplant the Basil Cuttings

Transplant each basil cutting into a pot with fertile soil that drains well. Place the pots in a location with plenty of light. Congratulations, you have successfully turned each leggy basil seedling into two individual basil plants!

If we had an unlimited number of grow lights, we would undoubtedly grow all our basil seedlings in perfectly lit conditions. However, since that’s not the case, we have found this method to be a fantastic way to consistently and quickly grow more basil plants throughout the year.

Four Reasons Basil Plants Get Leggy

To avoid leggy basil seedlings and plants in the future, it’s essential to understand why basil grows spindly. Let’s explore four common factors that contribute to leggy basil plants.

1. Nutrient-Rich Soil

When planting basil seeds, it’s crucial to use lean potting soil or a seed starting mix. Nutrient-rich soil can cause the plant to grow too fast, resulting in tall and weak seedlings. The seed itself contains all the energy required for germination and early growth, so a lean soil will provide the best environment for the seeds to thrive.

2. Insufficient Light

Basil requires at least six hours of full sun daily to grow and flourish. Inadequate light will cause seedlings to stretch and become leggy as they strive to reach more light. To combat this, consider using artificial grow lights to supplement natural light, especially in areas with limited sunlight.

3. Lack of Pruning

Though it may seem counterproductive, pruning basil is crucial for its overall health and compact growth. When the seedlings have at least 3-4 sets of true leaves, start pruning by cutting just above where new leaves are forming. This process encourages more leaves to grow, resulting in a healthier and bushier basil plant.

4. High Temperatures

While mature basil plants can tolerate temperatures up to 32 degrees Celsius (90 F), seedlings prefer a slightly lower temperature range. Aim for around 22-26 degrees Celsius (72-79 F) during germination, and then reduce it to 20-22 degrees Celsius (68-72 F) once the seedlings have sprouted. This will help promote strong and compact basil plants.

Leggy Thai and common sweet basil seedlings

Two starter pots with leggy seedlings in the making. Thai basil (left) and the more common or sweet basil (right).

In conclusion, leggy basil seedlings can actually be an opportunity to grow more basil plants. By following these steps and understanding the reasons behind legginess, you can successfully propagate and enjoy an abundance of fresh basil year-round. So go ahead, embrace those leggy seedlings and let your garden thrive with flavorful basil!