What it takes to be a giant

On a walk around the San Jose neighborhood, I encountered a single absolutely giant sunflower in a sidewalk garden.

giant sunflower

I admired the size of the flower head, which was about 16 inches across and probably weighed 10 pounds, wondering how many seeds must be packed in so very tightly and mathematically precisely (see an earlier post on “how many seeds in a sunflower seed head?”).

giant sunflower

Seeds are precisely arranged in spiral rows to maximize packing.

But then I got to thinking about what it takes to produce that giant flower head and develop all those seeds.  Supported by enhanced woody fibers in the stalk and fed by photosynthetic machinery in huge, oversized leaves and an elongated, deep taproot reaching deep into the soil for water and nutrients, the enormous reproductive output of this plant has the potential to be record-breaking.

But alas, a quick google search confirmed that Hans-Peter Schaffer holds the Guinness record for sunflower height (30 feet, 1 inch), mine was probably just over 8 feet. The giant Mongolian sunflowers routinely grow to 16-18 feet and sport 18-24 inch flower disks, so my giant wasn’t really record breaking at all. ¬†Still impressive for an herbaceous plant, though!