29 June 2025

If you planted giant common sunflower (Helianthus annuus) seeds in late April in Pittsburgh, they are probably(*) blooming now but the stalks have not reached full size.

Watch this time lapse video of sunflowers growing from seed to giants in 103 days. It takes them so long that it’s September before they’re done.

(*) p.s. It’s been a weird weather spring this year in Pittsburgh. Temperatures and precipitation were near normal in May except for a notable dip to 39°F on the 10th. However, April and June were both and 3+ degrees F above normal with 3 additional inches of precipitation. If your garden is not doing well it’s totally understandable.