I have chosen one of my favorite early spring bloomers as our April Plant of the Month for 2025. Blue wood phlox is a low growing groundcover which prefers shady areas from around the Kansas River eastward. Its one of my favorites because of its long bloom time and durability in the landscape. As a native plant, adding it to the landscape only helps with biodiversity.
Blue wood phlox comes in a variety of colors, despite its name. You will mostly find shades of blue or lavender, but pink and white forms are not unheard of. In fact, I have a habit of collecting samples of different colors and adding them to my garden spaces. In the garden, I like to use this plant as a border or edging in the shady areas. Along the east side of my property I have a Woodland Shade Garden, and I have added a row of blue wood phlox along the edge.
In the Garden with Blue Wood Phlox
As I mentioned above, I like to use blue wood phlox in the garden as a border plant. It also mixes into a large shade garden, providing early spring colors when only a trees and shrubs are blooming. I have an area along the south side of my landscape which was recently cleared by the gas company, but has a border of trees. As I clean up the tree lot, removing unwanted invasives, I am adding back in native trees, shrubs, and perennials. I plan to use a lot of blue wood phlox, especially white cultivars to lighten the area.
I have also utilized it in the gardens of several clients, to enhance their landscape. It often does bloom alongside Korean Spice viburnum, daffodils, crocuses, and other early bulbs. Altogether, these plants create beauty in the early garden time.
Surprisingly, I found blue wood phlox growing in the back of my grandmother’s garden, more 10 years after her passing. I still go by the forgotten garden in spring and summer and find things that have thrived despite the neglect of the garden.
Like all the phlox species, blue wood phlox (Phlox divaricata) is highly fragrant. It can and should be used anywhere that a breeze may waft over, scenting the garden.
Insect and Animal Associations
While blue wood phlox may not dazzle as a pollinator plant, it does get pollinated by a variety of insects. The flowers are tubular and reward long-tongued insects with nectar while they move pollen around. Because it blooms in April, there are less pollinators out, but bumblebees, long-tongued bees, bee flies, swallowtail butterflies, skippers, and moths do work the flowers.
Pests include leaf beetles, long-horned beetles, the phlox plant bug, the spotted straw moth, and a stalk borer moth. Deer and rabbits may occasionally eat the foliage. Now, I call these pests, but in reality they cause so little damage, that there is no treatment recommended. If you have a problem with deer, I suggest fencing or a dog.
Cultivars of Blue Wood Phlox
While you can certainly find just the seed grown plants, there are several cultivars now available, usually selected for flower color. Most seed grown plants turns out to be just blue or lavender colored. But I like to include variations of native plants in the garden, because they can also be found in nature. The only problem with native cultivars is that they are usually clones, not hybrids, so they may have less vigor and longevity.
- ‘Blue Moon’ was introduced by the New England Wildflower Society and has deep blue flowers with full petals.
- ‘May Breeze’ was selected by Piet Oudolf and has white or pale blue flowers.
- ‘Louisiana Purple’ has dark lavender flowers with a maroon eye.
- ‘Clouds of Perfume’ has very fragrant blue flowers.
Companion Plants
When designing a space for blue wood phlox, plan to use other native woodland plants, including perennials, groundcovers, and grasses. It goes great under any shade tree, even black walnut. I also like to mix in a few introduced shade plants, such as hostas and epimedium. But you choose what works best for you, or what you like the best. The following list includes several natives which are great companions for blue wood phlox, in the Central Great Plains Region.
- Virginia waterleaf, Hydrophyllum virginiana
- Yellow Wood Poppy, Stylophorum diphyllum
- Red columbine, Aquilegia canadensis
- Shooting star, Dodecatheon meadii
- Jack-in-the-pulpit, Arisaema triphyllum
- Cutleaf Toothwort, Cardamine concatenata
- Dutchman’s breeches, Dicentra cucullaria
- Bloodroot, Sanguinaria canadensis
- Maidenhair Fern, Adiantum pedatum
- Virginia strawberry, Fragaria virginiana
Conclusion
Blue wood phlox makes a great addition to the shade garden for early season beauty as well as for early pollinators. It is a low growing, groundcover type plant which reaches 6 to 8 inches tall and 12 to 18 inches wide. Readily spreading by seed, it can fill in empty spots within the landscape. Add it to the garden for an extra bright pop of color in spring!
Happy planting!
