Also known as bee balm, we had hoped when planting it that the monarda would feed our honey bees. Instead our little plot of it seems covered exclusively by bumble bees.
Ah, well. While the honey bee is inarguably the glamorous poster child for pollinators, chiefly because of her making a honey surplus which we can steal, the bumble is a worthy pollinator in its own right and even better suited for greenhouses, where a honey bee might fecklessly beat against the glass trying to return to the hive. Furthermore some flowers only reluctantly if at all yield their pollen to the gentle visitations of the honeybee, responding much more to the bumble’s vigorous buzz pollination, wherein the bee uses her flight muscles to vibrate loose the pollen. Honeybees seem capable of this activity but apparently do not much use it.
To return to our bee balm, its flower heads are actually composed of a great many individual tubular flowers, which we have learned are much too long for honey bee tongues to reach the nectar at bottom. Perhaps this lack of honey bee competition is why we saw not just the occasional bumble as on our other flowers but a crowd eagerly working the entire patch.
While we have not observed the behavior, some wasps will bypass the tubular obstacle and bite a hole at the base of a flower to reach the nectar. Afterwards honey bees may avail themselves of this breach.
As the series of sorry-not-very-good pictures at left shows (as usual, click to see a larger version), after the flower head forms, the first individual flowers begin to develop at the center, arcing outwards. As they bloom and are spent, the adjacent flowers develop forming a ring. The process repeats with a ring of blooms increasing in radius until the flower head has been traversed, the final tonsure drops off, and an entirely bald pate remains.
As a surprising variation on this typical development, on two of our score or so of plants it seemed as if a tubular flower had gone on to become a secondary flower head and sprout its own tubular flowers. Quite naturally, we thereupon imagined one of those sprouting a tertiary head, one of whose flowers would sprout a quaternary head, and so on but this did not occur. The process stopped at two heads. Nor did the secondary heads achieve the size of the primaries. We have neither heard nor read anything about such possibilities but perhaps there is a clue in that same flower bed.
Monarda is actually the name for a large family of flowers. Our bee balm is more specifically monarda fistulosa. Behind our patch of these tall plants is a group of shorter horsemint, which we learn is also a monarda, specifically monarda punctata. Horsemint, as the picture shows, is noted for having stacked tiers of blooms. The tiers can be quite close to each other, concealing their connecting stems and making for a very complex and dense flowering mass. Not so ours, which clearly show the sort of development we fancifully entertained for our bee balm oddities.
What then caused those oddities? Did some sort of monardic hybridization take place? Or is this capability in the bee balm genes but usually suppressed? Does either bee balm or horse mint or other monarda sprout two heads at the same tier? We do not know and look forward to enlightenment from gardeners wise in the ways of monarda.
Updated 2013-Oct-08 Greg Vaclavek of Ann Arbor’s Native Plant Nursery LLC reports having seen bee balm develop this way but not very often.