It is the beginning of summer and our garden is full of color. Our plant of the month is the striking Coral Bean (Erythrina herbacea) which is revealed to the eyes in a quiet corner of the garden (map attached) through the creamy fountains of the Mexican feather grass (Nassella tenuissima).
Erythrina is a worldwide tropical genus. Most species are trees and shrubs but in frost-bound regions there are species which exist as herbaceous perennials, dying back with the frost and reemerging in springtime from their woody rootstock – the caudex.
We encounter caudex plants in plant nurseries – those sculptural plants sold in small pottery, often erroneously called “Bonsai” and commonly named “Love Tree”. These are actually trees and shrubs with thick bases, which naturally develop underground, and are exposed by the grower for their impressive shape.
Erythrina herbacea is such a shrub. Its distribution is northern, from southeast U.S.A to northeast Mexico and its frost tolerance comes from the ability to resprout each spring from its subterranean caudex. The tall flower spikes are usually the first to grow, followed by the thorny leaf stems.
As a member of the Pea Family its flowers are papilionaceous but they do not seem like it. The petals known as wings and keel are hidden under the banner folded into a tube. This shape, along with the horizontal arrangement of the flowers on the spike, is adapted to pollination by hummingbirds as well as sunbirds. The seeds have a beautiful red color and are poisonous – you can look and touch but better not swallow…
You are invited to behold the coral redness and imagine the magnificence of the hidden caudex.