28 April 2010
In The Garden With the Fluvanna Master Gardeners
By Irene C. Burke - Fluvanna Master Gardener
Fluvanna County Extension Office: 434.591.1950
Each year the Perennial Plant Association (PPA) features the Perennial Plant of the Year. The winner must be suitable for a wide range of climate types, low maintenance, easily propagated, easily come(s) true from seed or vegetative propagation, and exhibit(s) multiple seasonal interest. The added bonus for this years selection is its native origins in central and eastern U.S. along with its adaptability to Virginias piedmont clay.
This year the PPA chose blue false (or wild) indigo (Baptisia australis). From my small survey of gardening friends and review of garden bulletin boards blue false indigo fulfills all the PPA promises.
Its blossoms are similar to sweet peas but instead of a vine, are held on a bushy clump of stalks resembling lupines. Colors range from pale blue to deep purple. At the bottom of each stem, buds bloom first, continuing until the last opens at the top. Hummingbirds, bumblebees and butterflies love them.
Baptisias pale green, spring leaves darken to a silvery blue by mid-summer. Though said to have no fragrance, some gardeners have noticed a delicate pineapple scent at dusk.
The flowers last about a month, late spring to early summer. Seeds looking like stout pea pods emerge in July. In autumn they blacken and rattle with the dry peas inside. So both bloom and pod will find an agreeable setting indoors in the hands of a creative flower arranger.
Children may use the clattering pods as a quirky toy. In the autumn, let them break open the pods after the amusement fades, then sow the seeds, pressing into the earth with but a half-inch cover of soil.
Show them also the source of the name blue wild indigo. Wearing gloves, slice a root and watch the ooze turn blue from its acquaintance with the air. Dab a piece of white cotton for full effect.
As a hardy native, Baptisia requires no fertilizer or pesticide treatments and needs no pruning, except the usual fall cleanup. Like all legumes, which peas are, it adds nitrogen to the soil. Set heavy feeding companions like delphiniums and dahlias alongside for this natural benefit.
From seed it is slow to establish, about 3 years before producing blooms but will flower after a year if bought in a three-gallon pot.
Blue false indigo needs full sun for heavy blooming and is drought tolerant once established, which means, unless there is a soaking rain, water deeply every 10 days to two weeks after planting until frost blackens the leaves.
Because it sends down a sturdy taproot, it is difficult to move; so select a site that is likely to remain permanent, preferably the back of the herbaceous border. Cuttings rather than division of an older plant, as well as spring seedlings are a better route to propagation.
It will flop if it gets too much water and too much shade. Give it at least 6 hours of direct afternoon sun with a neutral to slightly acidic soil pH of 6.5. Good drainage is essential; so a gentle slope will help with this dense clay. Or lighten the soil by thirds with compost and coarse sand. Windy, open locations will keep fungal diseases like powdery mildew at bay, though they cause negligible harm.
Not all American beauties are roses. Some come in hues the rose cannot offer like this wonderful blue wild indigo.
TIP OF THE WEEK
The out-of-place-plant a.k.a. weed is an opportunist. Therefore, when weeding have mulch ready to cover the bare spot or that weed will re-establish itself in the disturbed soil. It's like a party-crasher who slides into a vacant seat without anyone noticing.