This year I got no goldenrod, the area has all been taken over by an aster-like weed. Is it possible that it went dormant this year due to the dry heat, or should I view it as gone and just mow over the area and plant some more next year?
Goldenrod is pretty tough.
Unless you’re in the desert or had a really really severe drought it should pull through. Of course, if you’re cultivating it deliberately it might decide to croak. Better to pretend it’s a noxious weed and it’ll come back with a vengeance.
Seriously, I see tons of goldenrod thriving on roadsides in competition with the worst weeds in history, with no one watering or tending it. Maybe your problem is too much love (water, fertilizer)?
(this is not to suggest that goldenrod can’t make a good garden plant - there are varieties that are very decorative, not invasive, and of course don’t cause hay fever)