Baptisia – False Blue Indidgo Not Blooming After 4 Years

Question

Hi. I planted two baptisia (False blue indigo) plants on a northern facing back wall of our house in Harrisburg PA four years ago. Neither of them have ever bloomed. Each year they send up a good bit of foliage. One flops a little and the other stands upright. During the summer they get full sun during the day – mid-morning to evening. During the winter, they don’t get any sun, but I’ve cut the foliage down to the ground in the fall after it died back. I’m not sure what the problem is. I have two theories for why they aren’t blooming: 1. lack of sufficient sunlight in early spring when the sun isn’t quite overhead yet and 2. insufficient phosphate in the clay soil (i did a soil test and our soil is low in phosphate). By now, they seem established and to have grown sufficient taproots that keep them coming back every year. Any thoughts on why they aren’t blooming? Should I give up on them and rip them out? Should I keep waiting and hope they’ll finally bloom in year 5 or 6? Thanks!

Answer 1

Your soil test reveals the issue at hand! A lack of phosphorus on the soil will halt the blooming process. Here are some articles that will help:

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/phosphorus-plant-growth.htm

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/bone-meal-fertilizer.htm

https://www.gardeningknowhow.com/ornamental/flowers/baptisia/growing-baptisia-plants.htm