I keep honeybees and there are always lots of bumbles around. One plant I didn't hear anyone mention is wild marjoram. It is the queen of all my bee plants that they like the most. It is drought resistant and usually starts to bloom in July through August. An important time when there are fewer blossoms around. Wild marjoram is also a pretty tough plant if it gets roughed up. It seems to spread mostly by seeds. Another great flower for bumbles is purple tansy phacelia lacy. Not to be confused by tansy ragwort. I am using it as a cover crop and once your grow it, there are numerous seed pods to replant for the next year. As for the Asphalt guys....I can't imagine plants just wanting to grow right up in the asphalt, unless the asphalt is getting old and cracks are developing. And when that happens of course nature will try to fill those cracks with seeds that blow around. The only true way keep this from happening is to pull them out as soon as you see them
