We jokingly refer to safflower birdseed as crack for Cardinals. Since cardinals are typically more of a ground feeder, and are inherently more skittish than most birds at your feeders, having a single open feeder with Safflower is the way to go to give them a safe and comfortable place to eat their favourites. Squirrels and grackles don’t like it either, so its one feeder that will be left alone from their insatiable appetites! Other birds that will love it are purple finch, house finch, grosbeaks, and doves.
Update June 18 2020 – Seed prices are going up. Sadly and frustratingly, times being what they are, between the major uptick in demand for birdseed in general during Covid 19, lack of supply, big conglomerate hoarding, and in some cases borders closing to business, prices are going up effective of this date. Please be aware that seed prices will fluctuate during this time.