Baptisia australis

By John Proctor

Baptisia australis, (blue wild indigo, plains false indigo), is a North American wildflower with an endemic range covering much of the eastern US from Georgia to Texas and Vermont to Nebraska. What I didn’t know when I planted my B. australis seedling in 2001 was that it would take several years to flower. My sweet wife kept asking why I was growing “that scruffy thing” in our front yard, until in its fourth growing season it produced a splendid show of deep blue flowers and earned its position as one of our favourite plants.

Typical of plants of the plains it is very drought tolerant. It never needs watering in Dartmouth; ours has never received any irrigation. Good drainage is probably more important for surviving winter, which it does without extra protection. It has thick roots and is said to resent disturbance. The entire plant is completely pest free. When crocuses are passing their peak and snowdrops are nearly finished flowering, its purple-black shoots emerge at odd angles, none pointing vertically. Sturdy stems quickly become upright to hold the mass of foliage well off the ground. Our plant receives full sun until 3:00 p.m. and grows to 140cm. Though quite sturdy it does benefit from staking if exposed to high winds.

The leaves are bluish-green, smooth and palmate with entire margins. The foliage does not develop fully until after flowering, giving a vigorous, rounded shrubby appearance. The foliage is topped by long spikes of deep blue pea-like flowers, opening here from mid-June to mid-July. It can be used as a cut flower, providing a chance to see the sap turn purple on exposure to air. When mature the inflated seed pods turn black, of interest to flower arrangers, and the ripe seeds rattle like a child’s toy. The foliage also turns black with hard frost and can remain attractive for weeks after.

Seeds respond to treatment like other legumes, i.e., light sanding and soaking before planting. They do not require cold treatment. Germination is reliable but sporadic over up to two months. Dry stored seeds remain viable for years.

Apart from B. australis need for staking, my only regret is not having more of it. This past spring I started seed of B. minor (B. australis var. minor), advertised as identical to australis but growing only to 60 cm, and I am eager to see it flower in three years. Seeds of both are available from The Fragrant Path, Box 328, fort Calhoun, Nebraska, 68023, www.fragrantpathseeds.com, or by chance from various seed exchanges.

** John Proctor is the president of the Nova Scotia rock Garden Club.