Yellow Foxglove (Digitalis lutea) is a hummingbird magnet! I know, it surprised me, too. After all, aren’t hummingbird plants supposed to be red? Turns out, that any tubular shaped flower with sweet nectar can appeal to hummingbirds. I frequently see them, along with bumblebees, visiting yellow foxglove during its long bloom season of mid-June to mid-July, about the same time frame as their more common pink brethren.
When I first moved to Washington, I fell in love with everyone’s favorite weed: common foxglove (Digitalis purpurea). Since it thrives in my garden sans care, I reasearched foxglove species, suspecting that there would be others that were similarly easy.
I purchased seed of yellow foxglove and another species, Rusty foxglove (Digitalis ferruginea). I successful started both from seed and now I they are established in many parts of my garden–gleefully volunteering. Both grow in part or full sun, average soil and don’t need fertilizer or staking.
Both yellow and rusty foxgloves are short lived perennials. Like common foxglove, each basal leaf rosette takes a year of growth and establishment before they bloom. The second year they elongate into a tall raceme with flowers that open from the lower part of the stalk to the top over several weeks. Rusty foxglove blooms after the other two, beginning in mid to late July and reaches up to 40″ in a graceful, narrow spire. Yellow foxglove is shorter than the other two, usually topping out at 3′ in flower.
I have found that yellow and rusty foxgloves are longer lived that the purple type, which exhibits a typical biennial habit, usually not living more than 2 or 3 years. I have some clumps of yellow and rusty foxgloves that are going on 5 years old, by which time they can produce more than one flowering stalk and sometimes one that branches bountifully. In my experience, they start to peter out after that but that’s when the next generation of seedlings is up and blooming.
Since the basal clumps of leaves don’t take up much room vertically or horizontally, its easy to accommodate multiples. I always let a few produce seed, wanting to have plenty for succession, feeding pollinators, flower arrangements and to share with my gardening friends.
It is easy to tell these foxglove species apart when it comes time to thin volunteers. Yellow foxglove leaves are smooth, not fuzzy and have a yellow-green hue (middle image). Rusty foxglove leaves are smooth on top, a little hairy underneath, dark green and decidedly more linear than common foxglove (right). Like D. purpurea (left), the other species are very poisonous if ingested. This can be an advantage to preventing garden predation and pests, but something to be aware of if you have toddlers or pets. Thankfully, something in the garden undeterred by deer, rabbits or slugs!
Left--yellow foxglove with a pollinating visitor. Middle–groups of yellow foxglove; great for cut flowers and mass impact. Right–tall, stately rusty foxglove budded up and ready to start blooming.