Aralia cordata 'Sun King'

 Aralia cordata 'Sun King' has rocketed to stardom in the last several years and was named 2020 Perennial of the Year by the Perennial Plant Association. This wonderful plant was introduced by Barry Yinger of Asiatica Nursery, who brought it back from Japan. Barry brought a lot of great introductions into the country for the first time, often giving them appropriate names if their Japanese name wasn't valid. 'Sun King' was introduced to the wholesale trade by Terra Nova in 2011.

As a species, Aralia cordata is found in Japan, Korea, and eastern China. It grows to 6' or more (it's been reported over 8' in cultivation here in the states) and young shoots are cooked as a vegetable. It's the Asian counterpart to our native Aralia racemosa and is pretty similar. Both species inhabit similar niches in their range: woodland openings, woodland edges, and shaded areas of savannah. It's reportedly also closely related to another US native, Aralia hispida.

'Sun King' needs fairly good light to maintain a bright gold color. If it's in more shade it will turn chartreuse fairly quickly. So place it in bright shade, preferably with dappled light or even some direct morning sun.

'Sun King' will develop large compound panicles of white flowers, just like the plain green form of the species. Aralia flowers are generally very attractive to pollinators. Following the flowers, clusters of small black berries will form. None of my plants have done this yet, but I've always had to move away or move them before they've gotten fully mature! The berries pictured here are from a plain green A. cordata at Rotary Botanic Garden in Janesville, WI. 

It isn't a terribly picky or difficult to grow plant. I've had success with it in pots, in the garden in my silt loam here in z4, in clay-loam back in Sheboygan county, and in heavier clay soils in nursery display gardens. As long as it isn't too terribly wet or dry, it's easy to grow and worthy of its perennial of the year title. It does seem to best in fertile, well-drained soils, with some supplemental irrigation in summer. 

One of the most important things I need to stress about this plant is its mature size. Pretty much all of the commercial plant tags I've seen are incorrect, and online descriptions are often also misleading. Over and over I see this listed as growing only 3' tall x 3' wide. This plant will easily grow to 5' tall x 6' wide in 5-7 years, and larger over time. Barry's plant was certainly bigger than 3'x3' before the larger trade started growing it, judging by pics I've seen. So I'm not sure why this became the size everyone decided this would grow. A short 3 or 4 year trial maybe? I honestly don't know; but it's important to give this plant enough SPACE. Check out this specimen at Soule's Garden in Indianapolis eating its Hosta neighbors!

This is an excellent specimen or background plant for partial shade and it's easy to combine it with so many things. The compound foliage makes a good contrast with broad leaved plants like Hosta, Heuchera, Colocasia, Astilboides tabularis, Darmera peltata, Ligularia dentata, and a slew of others! The foliage is also bold enough to make a good foil for finer leaved plants like Iris, grasses and sedges, ferns, conifers, etc. 

I also think it's an excellent plant for a background to annuals and Rotary Botanic Garden made excellent use of it last time I visited. Don't be afraid to use it in beds with Coleus, or even in pots for a season and plant it in the garden at the end of the year. 

If you're not currently growing this in your shade garden, and you have the space, you really should add it. It's such a flexible plant and it's easy to grow. We'll be offering it again in the near future, probably available in late summer.