Plant potted or bare-root bee balm (Monarda) in spring or early fall, any time the soil isn't frozen (Prairie Moon). From seed, start indoors 6 to 8 weeks before your last frost and set plants out after the frost (Pinetree, Outsidepride), or sow outdoors in spring or late fall (Prairie Moon). Barely cover the seed, since it needs light (Texas Master Gardeners). Give it at least 6 hours of sun, 2 feet between plants for air flow (Iowa State), and divide every 2 to 3 years in early spring.
Bee balm is a North American genus in the mint family with about 25 species (NC State). The two you'll meet most are scarlet bee balm (M. didyma), a red-flowered plant of moist Appalachian woods and streambanks, and wild bergamot (M. fistulosa), a lavender-flowered prairie plant that handles drier soil (NC State, Wildflower Center). Many garden cultivars are hybrids of the two (Chicago Botanic Garden). Both are perennials that bloom in summer, spread by underground stems, and draw bees, butterflies and hummingbirds (NC State, Iowa State). Its other common name, Oswego tea, comes from its history as a tea plant; we don't cover herbal uses here.
When to plant bee balm
| Timing | What the sources say |
|---|---|
| 6 to 8 weeks before the last frost (seed indoors) | Pinetree and Outsidepride start seed indoors 6 to 8 weeks ahead; the Texas Master Gardeners chart says 8 to 10 weeks. Seed sprouts in about 2 to 3 weeks at 60 to 70°F (Pinetree, Texas Master Gardeners) |
| After the last frost (transplants) | Pinetree sets seedlings out after the last frost; Outsidepride hardens them off for 7 to 10 days first |
| Mid-spring to early summer (seed outdoors) | Pinetree sows outdoors from a few weeks before the last frost into early summer. Prairie Moon says wild bergamot can be sown on bare soil in spring without cold treatment, and that a mid-June sowing grows but won't bloom that year |
| Late fall or winter (dormant seeding) | Prairie Moon scatters seed on a weed-free surface in late fall or winter; Outsidepride also direct-sows in fall |
| Early spring, as shoots emerge (dividing) | Iowa State calls early spring the best time to divide; the Wildflower Center divides scarlet bee balm in spring before stems come up |
| April to May or October (bare-root plants) | Prairie Moon ships dormant bare-root plants in those windows and says they can go in any time the soil isn't frozen |
Use our planting calendar with your frost dates to count back 6 to 8 weeks for indoor sowing. Two things the sources disagree on. First, cold treatment: Outsidepride chills seed in the fridge for 4 weeks before indoor sowing, while the Wildflower Center and Prairie Moon say wild bergamot seed needs no stratification. Second, depth: the Texas Master Gardeners chart says surface-sow because light helps, and Pinetree surface-sows and covers lightly. Our reading is to press the seed onto the mix with only a dusting on top, and to try a short chill only if a first batch is slow.
How to plant bee balm
| Scarlet bee balm (M. didyma) | Wild bergamot (M. fistulosa) | |
|---|---|---|
| Hardiness | Zones 4a to 9b (NC State) | Zones 3a to 9b (NC State); 3 to 9 (Prairie Moon); 4 to 8 (Wildflower Center) |
| Light | Full sun, tolerates some shade (NC State) | Full sun (NC State); sun to part shade (Wildflower Center) |
| Soil | Rich, moist, well-drained, slightly acid (NC State, Wildflower Center) | Average to dry soils; tolerates clay (NC State) |
| Height | 2 to 4 ft, sometimes to 6 ft (Wildflower Center) | 2 to 4 ft (NC State); up to about 5 ft (Wildflower Center) |
| Bloom | Midsummer to fall in its native range, earlier in the Southeast (Wildflower Center) | July to September (Prairie Moon); May to September (Wildflower Center) |
| Start from | Division or late-spring softwood cuttings (Wildflower Center, NC State) | Seed, which the Wildflower Center calls very easy |
Spacing also varies by source: Pinetree sets plants 12 to 24 inches apart, Iowa State 2 feet, Prairie Moon 2 to 3 feet, and Outsidepride thins to 30 inches. Our reading is to use the wider end in humid climates, because air flow is the main defense against mildew (NC State, Iowa State).
Watering, feeding and pruning
- Keep it evenly moist. Iowa State waters every 7 to 10 days in dry weather, soaking the soil 6 to 8 inches deep, and mulches. NC State says drought-stressed wild bergamot gets more mildew. Water at the base, not over the leaves (NC State, Outsidepride).
- Feed lightly. A small amount of 10-10-10 around each plant in early spring is usually enough; Iowa State warns that too much fertilizer makes mildew worse.
- Deadhead. Removing spent flowers extends bloom (Iowa State) and cuts down on self-seeding (NC State). NC State says a late-spring or early-summer trim makes plants bushier and delays bloom.
- Divide often. Iowa State divides every 2 to 3 years into pieces with 2 or 3 shoots; the Wildflower Center says every 3 years; Outsidepride says 3 to 4. Chicago Botanic Garden notes that clump centers die out after 3 or 4 years, which is the sign it's time.
- Watch the spread. Some species spread quickly by rhizomes and can take over a bed (NC State). Digging out the edges each spring keeps it in place (GardenPal reasoning).
Bee balm in containers
Iowa State lists dwarf cultivars: 'Petite Wonder' and 'Petite Delight' (10 to 15 inches) and the Pardon My series (10 to 12 inches). These are the sizes we'd pick for a pot. Use a large container and water more often than in the ground, since dry stress invites mildew (GardenPal reasoning, based on NC State).
Fall and winter
- Fall planting works for potted and bare-root plants while the soil is workable (Prairie Moon).
- Stems for bees: NC State suggests cutting dead stems to 12 to 24 inches and leaving them standing, because native bees nest in the hollow stems.
- Diseased leaves out: Iowa State removes and destroys infected debris in fall. Our reading: clear the mildewed leaves but leave some clean stem stubs, which meets both goals.
- A summer reset: Chicago Botanic Garden cut plants to the ground in late summer when they looked worn, so clean foliage could regrow.
Powdery mildew and other problems
Powdery mildew is the main problem. NC State and Iowa State recommend full sun, good spacing and resistant cultivars. In a 1993 to 1996 Chicago Botanic Garden trial of 41 bee balms, 'Marshall's Delight' had 5% or less leaf coverage and 'Purple Mildew Resistant' stayed free of mildew. 'Colrain Red', 'Raspberry Wine', 'Rose Queen', 'Rosy-Purple' and 'Violet Queen' were also highly resistant. 'Gardenview Scarlet' and 'Colrain Red' are on Iowa State's resistant list too. The sources conflict on wild bergamot itself: NC State says it shows mildew resistance, and recommends 'Claire Grace', but the straight species was among the most susceptible in the Chicago trial. NC State also lists rust. Bee balm is resistant to deer and rabbits (NC State). The Wildflower Center rates deer resistance high for wild bergamot and moderate for scarlet bee balm.
Bee balm around the vegetable garden
Bee balm draws bees, butterflies and hummingbirds (Iowa State, NC State), and Prairie Moon lists wild bergamot as a host plant for the raspberry pyrausta moth. NC State says both main species tolerate black walnut. Chicago Botanic Garden suggests pairing it with phlox, irises, daylilies and yarrows. Because it spreads, our reading is to plant it at the edge of the vegetable plot rather than inside a bed. Good neighbors include daylilies, coneflowers, black-eyed Susans and irises; see also flowers that attract beneficial insects.
Frequently asked questions
When should I plant bee balm?
In spring or early fall. Prairie Moon says dormant bare-root plants can go in any time the soil isn't frozen. Seedlings go out after the last frost (Pinetree).
When do I start bee balm seeds indoors?
6 to 8 weeks before the last frost (Pinetree, Outsidepride). The Texas Master Gardeners chart says 8 to 10 weeks.
Do bee balm seeds need cold stratification?
The Wildflower Center and Prairie Moon say wild bergamot seed doesn't. Outsidepride chills seed for 4 weeks before indoor sowing.
How far apart should I plant bee balm?
About 2 feet (Iowa State). Other sources range from 12 inches (Pinetree) to 30 inches (Outsidepride).
How do I stop powdery mildew on bee balm?
Plant in full sun with good spacing, water at the base, don't overfeed, and choose resistant cultivars such as 'Marshall's Delight' or 'Purple Mildew Resistant' (Iowa State, NC State, Chicago Botanic Garden).
When should I divide bee balm?
In early spring as shoots emerge, every 2 to 3 years (Iowa State).
Enter your last frost date to time indoor bee balm sowing and planting out.
Open itSources
- Virginia Cooperative Extension, "Companion Planting in Gardening" (SPES-620P)
- University of Maryland Extension, "Vegetable Succession and Companion Planting"
- Oregon State University Extension, "Companion Planting"
- Penn State Extension, "Herbs Make Good Plant Partners and Companions"
- University of Minnesota Extension, "Planting the vegetable garden"
- USDA Plant Hardiness Zone Map
- NOAA NCEI U.S. Climate Normals (frost/freeze data)
- NC State Extension Gardener Plant Toolbox, "Monarda"
- NC State Extension Gardener Plant Toolbox, "Monarda didyma"
- NC State Extension Gardener Plant Toolbox, "Monarda fistulosa"
- Lady Bird Johnson Wildflower Center, "Monarda fistulosa"
- Lady Bird Johnson Wildflower Center, "Monarda didyma"
- Iowa State University Extension, "Growing Bee Balm in the Home Garden"
- Chicago Botanic Garden, Plant Evaluation Notes 12, "Monarda and Powdery Mildew Resistance" (PDF)
- Prairie Moon Nursery, "Monarda fistulosa (wild bergamot)"
- Pinetree Garden Seeds, "Wild Bergamot"
- Texas Master Gardeners (Orange County), "Seed Germination Chart"
- Outsidepride, "Monarda planting instructions"
Pairings are summarized in our own words from extension-service guidance. Research support for many companion effects is limited, so treat them as good habits, not guarantees.