Bee balm (Monarda) is a popular North American perennial valued for its unique flowers and aromatic foliage. Also called Wild Bergamot or Oswego Tea, it is commonly grown from seed, requiring gardeners to accurately identify the plant during its earliest stages. This guide focuses on identifying the young Monarda seedling to distinguish it from surrounding weeds.
Identifying the First True Leaves
The first structures to emerge are the cotyledons, or seed leaves, which are small, simple, and oval-shaped. These do not resemble the mature foliage of bee balm. Soon after, the first set of true leaves develops, arranged oppositely along the central stem.
These true leaves are key for identification and usually appear when the seedling is about a half-inch to one inch tall. Their shape is ovate to lanceolate (egg-shaped or spear-shaped). A defining feature is that the edges are distinctly serrated or finely toothed, contrasting sharply with the smooth cotyledons. Young seedlings may also exhibit a reddish or purplish tint under bright light or cooler temperatures.
Key Characteristics for Differentiation
A primary characteristic of Monarda seedlings is their scent, inherited from the mint family (Lamiaceae). Gently rubbing a true leaf releases a strong, aromatic fragrance, often described as a mix of mint and oregano. This distinct herbal aroma is present even in the smallest true leaves.
Another structural feature confirming its identity as a mint family member is the square, four-sided stem. If you roll the stem between your fingers, you can feel the four sharp angles. The small, light green stem may also show fine, sparse hairs, known as pubescence.
The Progression from Seedling to Juvenile Plant
Once the seedling develops several sets of true leaves, it enters the juvenile phase and adopts its adult growth habit. The plant grows taller, and the leaves become more deeply veined and robust, with a darker green color. At this stage, it focuses on root and foliage production rather than flowering.
The developing plant forms a basal rosette, a cluster of leaves close to the ground, preparing for vertical growth. As the juvenile plant matures, it produces shallow underground runners called rhizomes. This allows bee balm to form the dense clumps seen in mature gardens. Adequate spacing (18 to 24 inches apart) is recommended to ensure good air circulation and help prevent powdery mildew.