When should I plant dahlias to ensure optimal growth and a bountiful display of their stunning blooms? Is it essential to consider the climate and regional conditions before sowing these magnificent tubers? As spring approaches, what specific temperature range should I be vigilant about to determine the right moment for planting? Should I wait until the last frost has passed, or are there other indicators such as soil temperature or daylight hours that I should monitor closely? How does the variability in soil types impact the timing of planting dahlias? Moreover, what about the depth at which they should be planted—does this vary based on seasonal changes or the specific variety of dahlia? Could there also be a strategic advantage in staggering the planting dates to extend the flowering period throughout the summer months? What expert advice exists on avoiding common pitfalls associated with improper planting timing for these luxuriant flowers?