The Strelitzia

Strelitzia nicolai, commonly known as the giant white bird of paradise or wild banana

Ever since I was young, bird of paradise plants intrigued me. My grandparents had a giant Strelitzia in their garden in East London, South Africa. It was so exotic and bizarre that I took some time to believe that such a plant could exist in nature. The flowers look so bird-like that it's hard to believe its mere coincidence.

I never imagined I would live somewhere this plant would be so commonplace I would hardly ever give them a second look. But here I am now in South Africa where Strelitzias are one of the most common wild and planted landscape plants.
Strelitzia is a genus of about 5 or 6 species (depending on who you listen to) of monocot plants closely related to the bananas and even more closely related to Ravenala, the Madagascan plant known commonly as the Traveler's Palm.

Strelitzia is a primarily South African genus, though Strelitzia alba is also found in Madagascar. All these plants are subtropical and grow in fairly low rainfall areas, so they tolerate only minimal frost but are fairly drought tolerant. This time of the year is the season for the Strelitzia (Bird-of-paradise flower): Those glamorous flowers indigenous to South Africa.The leaves of most Strelitzias are ‘paddle-shaped' and resemble banana leaves only with longer petioles. A lot of people call the plant a wild Banana. Strelitzia juncea leaves are ‘paddle-less' once the plant is mature, leaving just pointed spikes. When young, most Strelitzias grow in a distichous pattern (leaves in only two ranks/planes), but as older plants begin to offset, the overall effect is of leaves growing in all directions, particularly in the smaller species. However, each individual plant remains truly distichous forever, unlike how bananas grow. The leaves of all these bird of paradise are thick and leathery, also unlike the thin, rubbery leaves of most true bananas. Leaves of this genus are listed as ‘possibly toxic' but few cases of actual toxicity exist in the literature, at least in small animal medicine..

(left) Leaves of normal Strelitzia reginae. (middle) A narrower-leaved version, folded in a bit due to the dry climate. (right), Close-up of Strelitzia reginae leaf.
The seeds are supposedly more toxic and will cause vomiting if ingested.

It is the flowers of this genus that attract the most attention. Here in South Africa these are also known as crane flowers, as they resemble the heads of the crowned crane. Strelitzia reginae is the most well known species and its flower is the most crane or bird-like.

(left) Strelitzia juncea flower. (middle) Strelitzia nicolai flowers. (right,) Strelitzia reginae flower

(left) Strelitzia reginae flower forming a second flower. (right) As it emerges from the spathe (the lower 'beak) base of the first flower.
The flower anatomy is not simply attractive, but functional as well. The blue ‘tongue' of the flower is the actual petals and contains the pollen (which can be seen if you spread apart the split down the middle of these petals.) At the base of the petals is where most of the attractive nectar ‘bait' is located. As a pollinating bird sits upon the petals to drink the nectar, the weight of the bird spreads apart the petals and the feet of the bird are covered in pollen. Then the bird proceeds onto the next flower, usually first alighting upon the stigma (that sticks out like a perch from the blue petals). As the bird sits upon this stigma, which is very sticky, it gets covered with pollen and the flower is fertilized!

Despite their tolerance for neglect, they do respond well to regular fertilization and will certainly flower more reliably if grown in rich acidic soils with a consistent application of balanced compost.
Pruning the smaller Strelitzias involves cutting or pulling dead leaves and flowers as close to the ground as possible, though I often see large public landscaped plants given 'hurricane cuts', where all the outer growth was cut down to around six inches above ground level, leaving only a narrow 'shuttle-cock' growth of leaves and flowers in the centre.
Others will even 'root-prune' around the edges of larger clumps, hacking at the plant a good few inches below the soil level all the way around the plant. This helps to keep plants a constant diameter, as some clumps, left unattended, can grow into shrubs dozens of feet in diameter and quickly outgrow its intended position.
I personally prefer to pull out old flowers and leaves, if possible, rather than cutting as this leaves less bulk and width of the clump and keeps the overall plant looking much cleaner. However, this method is not recommended for plants without good, sturdy root systems, or plants in pots (as you may end up pulling the whole plant out of the pot or ground). Keeping ahead on pruning is important as unattended clumps of Strelitzia get very messy and somewhat unsightly, and are very difficult to prune once they form a large, thick shrub.
Strelitzias can easily be grown from seed or the taking of sucklings from the mother plant.

Most of the photos were taken on my digital camera
Two were found on the internet.
source mostly general knowledge.
Technical names for the plants from http://davesgarden.com/guides/articles/view/1898/