Cardinal Lobelias

We all know of the lobelias that are neatly mounded for edge planting or trailing for hanging baskets. Those are the lobelias that are annuals with predominantly blue flowers. Change from the norm and try out cardinal lobelias!

Tall and stately cardinal lobelias (Lobelia x speciosa) are a garden cultivar that were bred from two veld flower species (L. cardinalis and L. siphilitica) that love to grow in natural wetland areas.

This plant is a deciduous, clump-forming perennial with a very erect growth habit, narrow leaves and terminal racemes of many two-lipped flowers that appear from mid-summer to late autumn.

Now that we have dealt with the basics of cardinal lobelias, we can wax lyrical about the latest hybrids, like the ‘Starship’ range. Flower colours range from very blue, to deep rose and scarlet red with either green or deep bronze leaves with maroon stems.

These plants have a columnar growth habit up to 60cm high and a well-branching spread of 30cm. They pack a powerful colour punch in even small garden spaces or as part of a mixed cottage-style container.

Cardinal lobelias love high temperatures, humidity and moist soil. They do not mind poorly drained soil or wet feet, as long as they are not constantly drowned, which means they will like growing near a water element. If the edges near your water feature, the eco pool’s water filtration bed, or any boggy area needs some colour, come aboard with ‘Starship’.

Most other spots in the garden will also do as long as it is not baking hot and dry. In hot gardens, morning sun and afternoon shade is perfect for them.

To give them the best chance, plant them in deeply cultivated, very fertile soil and water them regularly. Plant some ‘Starship’ lobelias now and you will have a great harvest of flowers on tall stems to arrange in your vases until late autumn, when the plants must be cut down to go dormant.