PL. —Monarda didyma 'Jacob Cline'Botanical illustration — drop image
Monarda didyma 'Jacob Cline'

Monarda 'Jacob Cline'

SpringSummerFall
4a9bHardiness zone
Peak bloom windowZone 6b · frost-offset weeks
Winter
Not in bloom
Spring
Peak bloom
Summer
Peak bloom
Fall
Not in bloom
Peak bloom
In bloom
Background

Monarda didyma 'Jacob Cline' is a cultivar of native bee balm producing tall stems of deep scarlet with aromatic foliage in the mint family. It draws hummingbirds, bumblebees, and native bees reliably through summer, making it a high-value planting for pollinator-focused gardens across eastern and central North America.

'Jacob Cline' shows improved powdery mildew tolerance relative to older bee balm varieties, though adequate air circulation still reduces disease pressure. The plant spreads by shallow rhizomes and forms expanding clumps that benefit from division every two to three years to prevent center die-out. Moist, organically rich soil and mulch over the root zone support consistent performance. Native to moist woodland edges and streambanks in eastern North America, it adapts well to garden borders with reliable moisture. Avoid overhead irrigation to further limit foliar disease.

Eastern Native American peoples, including the Oswego, used leaf preparations as a tea and to address colds, fever, and digestive complaints — giving rise to the common name Oswego tea. The foliage contains thymol and carvacrol, volatile compounds also present in thyme, which have documented antimicrobial properties.

Keep apart
Care guide
SunFull sun to part shade
WaterRegular
SoilMoist, well-drained, rich
Spacing18–24 in
Height36–48 in
Zone4a – 9b
Native RegionAL, CT, DE, DC, GA, IN, KY, ME, MD, MA, MI, NH, NJ, NY, NC, OH, PA, RI, SC, TN, VT, VA, WV, WI
Direct sowFrost hardy
Seasonal tasks
spring
cutThin new stems to 4–6 shoots per clump to open the interior and reduce powdery mildew pressure before stems reach full height.
sowDivide established clumps as new growth emerges, replanting outer sections 18–24 inches apart at the same soil depth. Discard the woody center.
summer
watchMonitor foliage for white powdery coating as warm, humid weather arrives. Remove affected leaves promptly and improve airflow around stems.
cutRemove spent stems back to a healthy leaf node after the main growth cycle to encourage lateral shoots and extended production through late summer.
watchCheck lower leaves for tan to brown lesions with dark margins indicating Monarda leaf spot. Remove affected foliage and switch to drip or base-level irrigation.
fall
cutCut all stems to ground level after hard frost. Seed heads may be left briefly for overwintering birds before clearing the bed.
Common problems

Powdery mildew

Symptoms

White or grey powdery coating on leaves — usually starting on older growth in humid conditions or when nights cool.

Treatment

Improve air circulation by thinning plants. Apply neem oil or potassium bicarbonate spray at first sign. Avoid overhead watering.

Fungal leaf spot

Symptoms

Brown or purplish spots on the leaves, often ringed with a yellow halo, that spread and merge in warm, humid, or wet weather; heavily spotted leaves yellow and drop early.

Treatment

Pick off spotted leaves and clear fallen debris to remove overwintering spores. Improve air circulation by thinning, and water at the base so foliage dries quickly. If it persists, apply a copper- or sulfur-based fungicide at the first sign.