Learn more about the growing habits of lemon verbena and how to care for it in both warm and cooler climates. We’ll look at container growing, common problems, and how to start new lemon verbena plants for your garden.
About Lemon Verbena
Lemon verbena has an intense fresh citrusy fragrance and flavor. It’s been called the truest and most intense of the lemony herbs.
This perennial shrub grows up to 26 feet high in South America, where it originated. In colder northern climates, it stays much shorter and needs extra protection during the winter.
If you decide to grow this delightful herb in your garden, there are several culinary ways to prepare it. Lemon verbena leaves add zest to teas, desserts, and fish and poultry dishes.
The leaves are most commonly used in recipes but you can also dry and candy the flowers of the lemon verbena plant. See our article on cooking with lemon verbena for more ideas on how to use this lemony herb in the kitchen.
Growing Lemon Verbena Plants in the Garden
Lemon verbena grows best in horticultural zones 8-10 and can reach heights up to 6 feet tall. The shrubs can grow to 2-4 feet in diameter, so give them plenty of space to spread over.
Like most herbs, lemon verbena thrives in a location that receives full sun and well-drained soil.
Even in such warm climates, it will require heavy winter mulching. Experts recommend cutting the plant down before mulching the roots for the winter.
In cooler climates, it won’t survive the winter outside. You can grow Lemon Verbena as an annual in the garden, buying new plants each spring.
When grown as an annual, it won’t reach the same height as in tropical areas. An Extension gardener in Washington State, zone 6, describes lemon verbena as a 3-foot shrub in her location and says it is most often treated as an annual.
You can also grow it in a pot, leaving it outdoors during the frost-free season. Here is a picture of the lemon verbena growing in my own garden. This plant is about one-year-old growing in a large planter. For reference, I am in zone 7.
Planting and Propagating Lemon Verbena
Growing lemon verbena from seed is not recommended. It’s better to buy established plants in pots or to start plants from softwood cuttings in the summer season.
Don’t plant lemon verbena outside until after frost since it is a tender plant. If you intend to leave it outdoors through the winter, start it early enough, so the roots are well established before the fall dieback.
How to Take Care of Lemon Verbena
If you’re growing lemon verbena as an outdoor annual, plant it in rich soil and fertilize it regularly with a foliar spray. Organic gardeners may use a seaweed/fish emulsion blend or compost tea.
If you plan to grow it as an outdoor perennial, you may want to fertilize more lightly—see the discussion above.
Fertilize regularly if you are growing lemon verbena plants in containers. Water lightly, since lemon verbena prefers well-drained soil, but don’t let it dry out.
Potted lemon verbena should be brought inside before the first frost and kept in a sunny place. Keep watering the plants through the winter, but cut back on fertilizing.
If you live in zone 9 or 10, you can cut back the top of your verbena plant and mulch heavily with straw or leaves. A lemon verbena shrub overwintered outdoors may not produce new leaves until early summer.
Common Problems With Lemon Verbena
Lemon verbena’s main problem is winter-killing, which has been discussed above. Aphids, whiteflies, mealybugs, or spider mites may also attack the plants.
You may be able to get rid of aphids by encouraging ladybugs. You can also use organic pesticides like pyrethrum or Safer’s insecticidal soap. If you spray pyrethrum outdoors, wait until dusk when you’re less apt to harm honeybees or other pollinators.
Propagation: Starting New Plants
Most gardeners buy starter lemon verbena plants from their local nursery or from online retailers like Bonnie Plants or Burpee. You can also find starter plants from local farms through the Etsy Marketplace.
If you have an existing plant, Lemon verbena plants can be propagated by softwood cuttings. This requires some care and attention. Here are some basic instructions for the process.
- Cut off a 4″ -6″ branch tip with a clean, sharp knife. Gently remove the leaves from the bottom few inches of the branch.
- Insert the bottom 2″ of the stem into a rooting medium like coarse sand, perlite, or vermiculite.
- Use a container with several drainage holes, and water the cuttings regularly.
More detailed instructions on starting herbs from cuttings are available from the Iowa State Extension office.
Growing Lemon Verbena in Pots
If you live in a cool climate (zone 7 and cooler) and want to keep lemon verbena alive through the winter, grow it in a pot. The University of Maryland Cooperative Extension recommends using 1-3 gallon pots, 8-12″ deep, in a soilless potting mix. Containers must have adequate drainage holes.
Place pots outside in full sun after the last frost. Bring them back inside before the first frost and set them in a bright space. They’ll need to be fertilized more in the summer than in the winter.
Harvesting Lemon Verbena
You may harvest lemon verbena leaves at any time. Their flavor is best just before its pale purple flowers open. The tenderest, most flavorful leaves will be at the tips.
If you prune off branch tips your verbena plant will become more thick and shrubby. Try not to cut off more than a third of the plant at any given time.
Fresh leaves are tough, so they should either be chopped fine or (if in liquids) removed after releasing their flavor.
Preserving Lemon Verbena
Lemon verbena is a popular herb to dry for tea. Sarah Garland writes that dried lemon verbena leaves, stored in an airtight container, will keep their fragrance and flavor for several years.
Wash leaves and pat them dry before preserving them. You can then dry lemon verbena in one of several ways:
- Bundle and hang it inside a paper bag to keep dust off
- Spread it on a drying screen at room temperature.
- Microwave it (follow the instructions in your microwave guide since power levels vary widely)
- Place it in a 100-degree conventional oven. Finish air-dried herbs off at 100 F if they have not air-dried completely within two weeks.
You may also candy lemon verbena leaves by brushing them with egg white and sprinkling them with sugar. Candied leaves will keep for months and may be used for cake decorating.
Summary
Lemon verbena takes a bit of extra coddling, but its true, intense fragrance and flavor make it well worthwhile. Check with local gardeners or with your Cooperative Extension about how it handles the winters in your climate.
While it needs careful handling in cooler climates, its fresh, pungent scent and flavor make that coddling worthwhile.