Tips for Growing Lemon Verbena Indoors

Our guide to growing lemon verbena discusses all you need to know to grow this versatile herb outdoors.

This article focuses on cultivating lemon verbena indoors.

Here’s what we’ll cover:

Get your garden tools ready!

Lemon Verbena Propagation

To begin, you’ll need seeds, a softwood cutting from an existing plant, or a nursery start.

Let’s discuss each method in a bit more detail.

From Seed

Starting from seed is the most challenging propagation method. Lemon verbena does not produce an abundance of viable seeds, and they generally have a low germination rate, taking a while to sprout.

However, if you can obtain seeds through harvest or purchase, try them.

Here’s how:

Start by filling a seed-starter tray or three-inch starter pots three-quarters full of good quality all-purpose houseplant potting soil that contains both organic and inorganic matter. It should be moisture-retentive and well-draining.

Put on the domes to create mini self-watering greenhouses.

Place the vessels in a location with bright, indirect sunlight, about three feet from a south- or east-facing window.

If your home is cooler than 70°F, use a heat mat beneath the containers to keep the soil warm.

From Softwood Cuttings

Instead of seeds, in the spring, when there is tender new foliage, you can take stem cuttings from an existing plant to start new ones. Here’s how:

Sanitize garden scissors with a 10 percent bleach solution (nine parts water to one part bleach), rinse, and allow them to air dry.

Cut a stem about five inches long from the tip at a 45-degree angle just above a pair of leaves. Cutting at this natural growing point encourages new stems to sprout in place of the old.

Snip off the bottom leaves so you have about one inch of bare stem. Dip the cut end of the stem into rooting hormone powder.

Fill a four-inch container three-quarters full of potting soil. Use a toothpick to make a hole in the center of the soil that is an inch deep and a little wider than the stem.

Put the stem into the hole and backfill to hold it upright. The lowest leaves should sit just above the soil surface.

Water lightly. Place in bright, indirect sunlight, and maintain even moisture.

New foliage is evidence of successful root formation.

From Seedlings/Transplanting

When seedlings are two to three inches tall and cuttings are producing new leaves, they are ready for transplant to permanent containers.

Select an unglazed porous terra cotta pot with at least one drainage hole. Using unglazed terra cotta allows evaporation of excess moisture and helps to prevent the soil becoming waterlogged.

The pot should be about two inches wider and deeper than the root ball.

Sanitize the container with a mixture of nine parts water to one part bleach, then rinse and dry.

Whether you are transplanting a seedling, cutting, or nursery start, you’ll want to note the depth it sits in its current container so you can replicate that depth in the new one.

Water the seedling, cutting, or nursery start the day before you intend to repot unless it’s already moist.

Fill the new vessel about two thirds full of houseplant potting soil. Packaged products generally have an appropriate pH in the 4.5 to 7.8 range that lemon verbena requires.

Make an appropriately sized hole in the soil and gently unpot the plant and set it in the hole, ensuring that it’s sitting at the same height it was in the previous pot.

If you’re using a biodegradable seed starter container, you can set this into the hole. Backfill and tamp the soil to remove any air pockets.

With our plants underway, let’s find out how to provide long-term care.

How to Grow Lemon Verbena Indoors

Choose a location with bright, indirect sunlight – a couple of feet away from a south- or east-facing window is ideal.

Water when the top two inches of soil are dry or use a moisture meter. Use a watering can to water at the soil level, not over the leaves, to inhibit fungal development.

Fertilize in the spring when the first new leaves appear and again about eight weeks later.

Use a liquid houseplant food diluted to half-strength to avoid burning tender roots.

Here’s how:

Grasp the three to four pairs of new leaves at the tip of a soft young stem.

Use your fingernails or garden scissors to snip the leaf cluster off just above a leaf node. This natural growing point will sprout laterally to produce a more compact, less leggy form.

Pinching back tip foliage also inhibits blooming and extends the growing season.

Let’s recap.

Growing Tips

For best results growing lemon verbena indoors:

• Use a porous terra cotta pot with drainage holes that’s two inches wider and deeper than the root mass.
• Choose a location with bright, indirect sunlight.
• Water when the top two inches of soil are dry.
• Apply diluted liquid fertilizer when spring foliage appears and eight weeks later.
• Pinch back the leaf tips for a compact form and to inhibit blooming.

Maintenance

Repot every three to five years, or when the roots start to grow out of the drainage hole.

Select a container that’s two inches wider and deeper than the size of the root ball, but avoid the temptation to use a larger vessel to save repotting next time. Extra soil in large containers can retain too much water, causing rot.

In late spring, you can prune to maintain a size and shape you find manageable and attractive.

Use sanitized pruners to remove unwanted stems, or any that have become damaged or affected by pests or disease. Make cuts just above leaf nodes to jumpstart regrowth.

Houseplants in dry homes, with humidity below 30 percent, are more likely to be susceptible to the following pests:

These sapsucking insects cause foliar discoloration, desiccation, and leaf drop as they feed.

A strong rinse under the shower and an application of organic fungicidal, insecticidal, miticidal neem oil is generally adequate treatment.

As for disease, overwatering may invite a proliferation of fungal spores. One infection to be aware of is powdery mildew.

This fungal condition proliferates in moist conditions and causes a whitish-gray, fuzzy coating on the foliage. Untreated, the leaves turn yellow before drying up and dropping.

Avoid overwatering and treat affected foliage with neem oil. Decrease the ambient humidity if it is over 50 percent.

You can learn more about powdery mildew in our guide.

Harvesting and Preserving

To harvest lemon verbena leaves, grasp the growing tip and pinch it off as discussed above, or snip off individual leaves as desired.

To dry the leaves, cut stems as you would for a bouquet. Use clean shears to make cuts just above a leaf node.

Rinse the leafy stems, shake off the excess water, and use a clean string to tie them together in a bunch.

Suspend the bunch upside down for a few weeks in a warm, dry, airy location.

When they are dry, gently detach individual leaves with your fingers or clean scissors and store them in an opaque airtight container in a cool, dark, dry location.

Dried leaves should remain fresh for up to two years for many cups of citrusy tea. Learn more about how to make lemon verbena tea in our guide.

Finally, remember the one-third rule: to avoid shock, do not remove more than one-third of an entire plant volume at once.

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