A Growing Journey: How to Grow Lemon balm

How to Grow Lemon Balm

Getting started with lemon balm doesn’t require a massive investment, which is part of its appeal. I’ve grown it successfully from both seeds and small plants, and each approach has its merits depending on your patience level and budget.

Essential Materials

For seeds or young plants, you’ll want to source them from a reputable garden centre or nursery. I’ve had good results with both approaches, though seeds are considerably cheaper if you’re planning to grow several plants. You’ll need some decent multipurpose compost, ideally peat-free (the quality of peat-free composts has improved considerably over recent years). A container with drainage holes is essential if you’re not planting directly in the ground. I use terracotta pots around 20-25cm in diameter, though plastic works just as well and retains moisture better during dry spells. If you are a keen herb grower you may also like our guide on why your sage plant keeps dying (and how to fix it).

For soil preparation, you might need some well-rotted compost or manure if your soil is particularly poor, though lemon balm isn’t terribly fussy. A small hand trowel and fork are useful for preparing the planting area. If you’re starting from seed, you’ll need seed trays or small pots for germination. I’ve found that 9cm pots work brilliantly for this purpose.

Optional but Helpful Items

A watering can with a fine rose attachment helps with young seedlings, preventing them from being flattened by heavy water flow. I keep a pair of scissors dedicated to herb harvesting, as they’re sharper and cleaner than secateurs. If you’re planning to dry the leaves, you’ll want some breathable bags or a drying rack. A small notebook has proved invaluable for tracking when I planted, when it germinated, and which location worked best, though I admit I’m not always disciplined about keeping it updated.

Plant labels are surprisingly useful, particularly if you’re growing several herb varieties. I learnt this the hard way after mixing up my lemon balm with apple mint seedlings. They look remarkably similar when young, and I only discovered my mistake when they matured enough to show their distinct characteristics. You might also find growing bay trees from scratch: a gardener’s complete guide helpful.

Step-by-Step Instructions

Choosing Your Growing Location

Location makes a substantial difference to how well your lemon balm performs. I’ve grown it in full sun, partial shade, and even quite shady spots, and each produces different results. In my experience, partial shade works best in most British gardens. Full sun can cause the leaves to become a bit tough and less fragrant during hot spells, whilst too much shade produces leggy growth with less flavour.

The soil should be reasonably well-draining but moisture-retentive. I’ve got heavy clay in parts of my garden, and whilst lemon balm tolerates it, the plants in improved soil definitely perform better. If your soil is very heavy, work in some compost or grit to improve drainage. Conversely, if you’re on sandy soil like parts of Surrey or Norfolk, adding organic matter helps retain moisture during dry periods.

Consider accessibility when choosing your spot. You’ll want to nip out regularly to harvest leaves, so placing it near the kitchen door makes sense. I’ve got a plant near my back step that gets used far more than the one at the bottom of the garden, simply because it’s convenient. Wind protection is worth thinking about too. Whilst lemon balm isn’t particularly fragile, a sheltered spot produces bushier growth.

Starting from Seed

If you’re growing from seed, start them indoors between March and May. I usually begin mine in April, which gives them time to establish before summer without requiring artificial heat. Fill your seed trays or pots with moist compost, pressing it down gently but not compacting it too firmly. Lemon balm seeds are tiny, so sow them on the surface and barely cover them with a fine sprinkling of compost. They need light to germinate, which is why covering them deeply is a mistake I made early on.

Keep the compost consistently moist but not waterlogged. I cover my trays with clear plastic propagator lids or even just a clear plastic bag supported by sticks to maintain humidity. Germination typically takes between 10 and 20 days, though it can be variable. Temperature affects this considerably, with warmth speeding things up. I keep mine on a bright windowsill in an unheated room, which works fine.

Once seedlings have developed their first true leaves (the second set that appear), you can prick them out into individual pots. Handle them by their leaves rather than stems, as the stems are more fragile at this stage. Grow them on in these pots for several weeks until they’re around 10cm tall before considering planting out.

Planting Out Young Plants

Whether you’ve raised seedlings or bought young plants, wait until after the last frost before planting out. In most of the UK, this means late May or early June, though southern gardeners might get away with late April. I’ve risked it earlier and lost plants to unexpected cold snaps, so I tend to err on the side of caution now.

Prepare your planting area by removing weeds and working in some compost if needed. Dig a hole slightly larger than the root ball, and water it before planting. Remove the plant from its pot carefully, teasing out any circling roots gently. Place it in the hole so it sits at the same depth it was growing in the pot, then backfill and firm gently. Water thoroughly after planting.

If you’re planting multiple lemon balm plants, space them about 30-40cm apart. They’ll fill out considerably, and adequate spacing improves air circulation, reducing disease risk. In containers, one plant per 20cm pot works well, or you can plant three in a larger container of about 40cm diameter for a fuller display.

Watering and Feeding

Young plants need consistent watering until established, which usually takes about four to six weeks. After that, lemon balm is reasonably drought-tolerant, though it performs best with regular moisture. I water mine during dry spells, particularly container-grown plants which dry out faster. The leaves will wilt slightly if they’re getting too dry, which serves as a useful indicator.

Feeding isn’t strictly necessary if your soil is decent, but I give mine a liquid feed every few weeks during the growing season. I use a general-purpose organic liquid fertiliser diluted according to the instructions. Container-grown plants benefit more from feeding than those in the ground, as nutrients leach out more quickly. Overfeeding produces lush growth but can reduce the concentration of the aromatic oils that give lemon balm its flavour, so moderation is sensible.

Maintenance Throughout the Season

Regular harvesting actually improves plant health and encourages bushier growth. I cut stems back by about a third whenever they start looking leggy, which happens several times during the growing season. This prevents flowering, which is desirable if you want to maximise leaf production. The plant puts energy into seeds once it flowers, and leaf quality declines somewhat.

That said, I do let one of my plants flower because bees absolutely adore the small white blooms. It’s a proper bee magnet during summer, and watching them work the flowers is lovely. If you’re not bothered about maximum leaf production, letting some stems flower is good for wildlife. Just remove the flowers after they fade to prevent excessive self-seeding, unless you want seedlings appearing everywhere.

Weeding around young plants is important, but once established, lemon balm competes well with most weeds. I apply a mulch of compost around the base in spring, which suppresses weeds and feeds the plant gradually. Keep the mulch away from the stems themselves to prevent rotting.

Common Mistakes to Avoid

Planting in the Wrong Location

The biggest mistake I made initially was planting lemon balm in a formal herb bed alongside more restrained plants. Lemon balm spreads by underground runners (rhizomes) and also self-seeds enthusiastically. Within two seasons, it had muscled out my French tarragon and was competing with everything nearby. It’s not as aggressive as mint, which is why some sources describe it as well-behaved, but it’s certainly not static.

If you’ve got a small garden or want precise control, containers are genuinely the best option. I grow most of mine in pots now, which completely prevents spreading and makes the plant more manageable. If you do plant in the ground, choose a spot where spreading won’t matter, or be prepared to dig up excess growth each spring. Some gardeners plant it in a sunken container with drainage holes to restrict root spread, which works reasonably well.

Neglecting to Harvest Regularly

Lemon balm grows quickly during the main season, and if you don’t harvest regularly, the stems become woody and less productive. I’ve seen people treat it as an ornamental plant, leaving it to do its own thing, then wonder why it looks tatty by midsummer. Regular cutting back keeps it producing fresh, tender growth with the best flavour.

Don’t be timid about cutting it back hard. I remove up to half the growth every few weeks during peak season, and the plant responds with vigorous new shoots. If it flowers and sets seed, it essentially shuts down for that growing period, so stay on top of it if you want continuous harvests.

Overwatering Established Plants

Whilst young plants need consistent moisture, established lemon balm is quite drought-tolerant. I’ve killed more plants through overwatering than underwatering, particularly in containers. Heavy, waterlogged soil leads to root rot, and the plant quickly declines. Make sure containers have adequate drainage holes, and don’t leave them sitting in saucers of water for extended periods.

In the ground, this is less of an issue unless your soil has poor drainage. If puddles form and sit for hours after rain, your drainage needs improving before planting herbs. Working in grit and organic matter helps considerably with heavy soils.

Ignoring Winter Protection

Lemon balm is technically hardy in most of the UK, dying back in winter and regrowing from the roots in spring. However, container-grown plants are more vulnerable to hard frosts because their roots are above ground level. I’ve lost pots during particularly harsh winters when I left them exposed.

Moving containers against a house wall or wrapping them with bubble wrap or hessian provides useful protection. In the ground, a mulch over the root area helps, though this isn’t essential in milder regions. I’ve had plants sail through winter in sheltered spots in the southeast without any protection, but Scottish and northern growers might need to take more precautions.

Expert Tips

Harvesting for Maximum Flavour

The aromatic oils in lemon balm leaves are most concentrated in the morning after dew has dried but before the day heats up. I try to harvest between about 10am and midday when possible. Cut stems rather than picking individual leaves, as this encourages bushier growth. Use sharp scissors or secateurs to avoid damaging the plant.

For fresh use, lemon balm keeps for a few days in a glass of water on the kitchen counter, much like cut flowers. For longer storage, I wrap the stems loosely in damp kitchen paper and keep them in the fridge, where they last about a week. The leaves are quite delicate, so handle them gently to avoid bruising.

Drying and Preserving

If you want to dry lemon balm for winter use, harvest just before flowering when the aromatic oils are at their peak. Cut whole stems and tie them in small bunches, hanging them upside down in a warm, dry, dark place with good air circulation. An airing cupboard works brilliantly, or a spare room out of direct sunlight.

I’ve found that lemon balm loses flavour quite quickly when dried compared to some other herbs. It’s still pleasant, but the intense lemon scent fades within a few months. Storing the dried leaves in airtight containers away from light helps preserve what flavour remains. Freezing is actually better for maintaining flavour. I chop fresh leaves and pack them into ice cube trays with a little water, then pop out the frozen cubes and store them in freezer bags.

Propagation Techniques

Once you’ve got an established plant, you can easily propagate more for free. Division is the simplest method. In spring or autumn, dig up the plant and split it into sections, each with roots and shoots. Replant these immediately, and they’ll establish quickly. I do this every few years anyway to rejuvenate older plants that are getting congested.

Softwood cuttings work well too. In late spring or early summer, take 10cm cuttings from non-flowering shoots. Remove the lower leaves and push them into pots of moist compost, then cover with a clear plastic bag to maintain humidity. They usually root within three to four weeks. This method is useful if you want to increase stock without disturbing the parent plant.

Dealing with Self-Seeding

If you let your lemon balm flower, you’ll get seedlings appearing the following year. Some people find this annoying, but I actually use it to my advantage. I let one plant flower each year, then pot up the best seedlings in spring to give away to friends or use elsewhere in the garden. The rest get weeded out whilst they’re small and easy to remove.

Seedlings don’t always appear exactly where you want them, often popping up in cracks in paving or at the base of other plants. Check regularly in spring and remove unwanted seedlings before they become established. They’re easy to spot because they have that distinctive lemon scent when you brush against them.

Frequently Asked Questions

Can I grow lemon balm indoors on a windowsill?

Yes, lemon balm grows reasonably well indoors, though it won’t be quite as vigorous as outdoor plants. Choose a bright windowsill, preferably south or west facing, and use a pot at least 15cm in diameter with good drainage. Indoor plants tend to be more susceptible to aphids, so check regularly and wash off any pests with water. The main challenge indoors is that lemon balm naturally wants a dormant period in winter, so it might look a bit sad during the darker months even with good care. I keep mine outdoors and bring a pot inside temporarily when I want fresh leaves during winter, then return it outside after a week or two.

How quickly does lemon balm grow from seed?

From sowing to harvestable plant takes about three to four months under good conditions. Seeds germinate within two to three weeks, then seedlings need another six to eight weeks growing on before they’re ready to plant out. After planting out, allow another month before harvesting properly. I sow mine in April, plant out in June, and start regular harvesting from July onwards. Bought plants obviously give you a head start, reaching useful size within four to six weeks of planting out. By the second year, plants are substantially larger and more productive.

Will lemon balm survive winter in a pot?

Container-grown lemon balm is hardy enough for most British winters if given some protection. The main risk is the compost freezing solid, which damages roots. I move my pots to a sheltered spot against the house wall and group them together for insulation. Wrapping pots with bubble wrap or hessian provides extra protection during cold snaps. In mild winters, particularly in southern and western areas, pots often survive without intervention. The foliage dies back completely, which looks dead but is normal. New growth emerges from the roots in spring, usually from April onwards.

Can I use lemon balm straight from the garden?

Absolutely, fresh lemon balm is brilliant straight from the plant. I rinse it briefly under cold water to remove any dust or insects, then use it immediately. It’s lovely torn into summer salads, added to fruit salads, or steeped in hot water for tea. The flavour is much more intense and complex than dried lemon balm, with a proper citrus punch. I also muddle fresh leaves into cold drinks during summer. For cooking, add it at the end rather than cooking it for extended periods, as heat diminishes the delicate flavour. Fresh leaves make a pleasant garnish for desserts too.

What pests and diseases affect lemon balm?

Lemon balm is remarkably trouble-free compared to many garden plants. Aphids occasionally cluster on new growth, particularly on indoor plants or during warm, dry weather. I just wash them off with a strong spray of water rather than using any treatments. Powdery mildew can appear on leaves in late summer, especially if plants are stressed by drought or overcrowding. Improving air circulation and watering properly usually prevents this. If mildew does appear, I cut affected growth back hard and bin it rather than composting. The plant regrows cleanly. I’ve never had serious pest or disease problems with lemon balm outdoors. The aromatic oils actually seem to deter many pests.

How do I stop lemon balm taking over my garden?

Growing in containers is the most effective method for complete control. If you’ve already planted it in the ground, you’ll need to manage its spread actively. Dig up spreading roots each spring before new growth starts. A spade pushed vertically around the plant cuts through runners effectively. Remove any seedlings that appear, which is easiest when they’re small. Deadheading flowers before seeds form prevents self-seeding, though you need to be vigilant as the flowers are quite small and easy to miss. Alternatively, embrace its spreading nature and plant it where that characteristic is useful, such as filling a difficult shady corner or banking. I’ve seen it used as informal groundcover very successfully in larger gardens.

Last Thoughts on Lemon Balm

Growing lemon balm has proved to be one of the more straightforward and rewarding herb projects I’ve undertaken. It’s forgiving of mistakes, produces abundantly, and actually seems to thrive on neglect once established. The key lessons I’ve learnt are to give it adequate space (or grow it in containers), harvest regularly to keep it productive, and don’t be afraid to cut it back hard when needed. Understanding its spreading habit from the start saves frustration later. Whether you want fresh leaves for summer drinks, dried herb for winter teas, or simply a fragrant plant that supports pollinators, lemon balm delivers reliably. I’d recommend starting with one plant and seeing how you get on. If it suits your garden and you enjoy using it, propagation is easy and you’ll have plenty to share. Give it reasonable soil, adequate moisture during dry spells, and regular harvesting, and you’ll have productive plants for years to come.

Author: Megan Walker

Megan focuses on seasonal food, kitchen garden growing, and how households can reconnect with where their food comes from. Her writing blends practical growing advice with ideas for cooking and eating in season. With a passion for fresh ingredients and sustainable living, Megan’s articles help readers make the most of local produce while supporting British farms.