Baptisia australis is another classic, well-known native garden perennial with midwestern origins. It is perhaps better known as false indigo, but I really dislike the idea of implying that a plant whose existence is true is somehow…false. So I call it Wild Indigo!
Wild Indigo is know for its tall indigo colored flower stalks which grow on a broad leafy base. The plant has a beautiful contrast to it, which makes a sharp display in early summer.
It is a nitrogen-fixing plant, so it can play a great role in adding extra fertility to the garden.
What Is Nitrogen Fixation?
Nitrogen fixation is essentially when a plant can convert atmospheric nitrogen into a form which can be used in the soil by plants.
Generally, if a plant can fix its own nitrogen, it can more easily become independent and live in more challenging contexts with lower fertility.
Top growth starts off slowly in the first couple of years while wild indigo it builds its large root mass, but then over time it becomes quite a wide shrub with a height of about four feet.
It has a number of uses in herbalism, including as an aid for sore throats. It is not as well known in herbalists circles as its close relative Baptisia tinctoria, however Michael Moore considers all of the Baptisia genus members to be interchangeable medicinally (https://swsbm.org/wp-content/uploads/2025/11/BptisFol.pdf). In that case it’s use could be extended to include “…antiviral and antibacterial properties…respiratory viruses and for gastrointestinal infections.” (see the 7song herbal database).
Growth Parameters:
Expect a crowning garden perennial about 4 feet tall. The more sun the better. Not too picky about soil texture.
