Heliconias add a touch of the tropics to hot and humid gardens

Rate this item
(1 Vote)

Heliconia rostrata Image by William Pomares from PixabayHeliconia rostrata Image by William Pomares from PixabayTropical gardeners are lucky to get some of the most fascinating flowering plants to grow, and Heliconias, also commonly called Lobster Claws, Parrot Flowers, and False Bird-of-paradise, are one of them, and sure to command attention all summer long. Learn how to grow them successfully below.

Heliconias bloom all summer long and their brightly coloured waxy bracts can be either upright or pendulous, and the flower bracts range from orange to red and yellow, pink and even green, or a combination of these, often tipped with a bright gold splash. The small true flowers peep out from the bracts, and depending on the species, can be hues of reds, oranges, yellows, and greens. Flowers do not appear until this perennial is two years old. The purplish-blue fruits are primarily dispersed by birds.

Heliconia' Red Iris' Picture courtesy PixabayHeliconia' Red Iris' Picture courtesy PixabayThe various species vary greatly in height, from +-15cm to over 6m tall, and they are all herbaceous or non-woody plants that spread by rhizomes, with each stem only flowering once, before drying up and collapsing. The growth habit and leaves of heliconias are very similar to gingers, cannas, strelitzias, and bananas, to which they are related, with large leaves and flowers that immediately remind you of a tropical paradise. The common name false bird-of-paradise refers to their close similarity to the bird-of-paradise flowers (Strelitzia).

Heliconia is a single genus with approximately 350 species, mainly from Central and South America. A small group of about 6 species have evolved separately in the South Pacific, and these are typically characterized by having green inflorescences. In the wild they can be found growing in humid tropical rainforests, in clearings in the forest floor where the sunlight can penetrate, and along river banks. Forest hummingbirds and butterflies like to drink the sweet nectar from the flowers; and the Honduran White Bat lives in tents it makes from the leaves.

Uses:

Some species of heliconia last well in a vase and are grown commercially for the florist's trade.

Heliconia psittacorum 'Pink and Orange' Image by virginie l from PixabayHeliconia psittacorum 'Pink and Orange' Image by virginie l from PixabayIn the Garden:

Heliconias form the centrepiece of so many tropical landscapes all around the world, and a single well-established colony immediately adds a sense of elegance and class to any garden large or small. Smaller growing cultivars will thrive in pots, rewarding the grower with an unending supply of magnificent blooms.

Cultivation:

Ideal growing conditions are humid and warm, similar to a tropical rainforest, and in South Africa heliconias grow best in humid sub-tropical regions like Kwa-Zulu Natal. In cold regions they can only be grown in heated glass-houses. Understanding the native growing conditions of Heliconia should aid in providing the appropriate conditions for growing them.

In the rainforests they thrive in the leaf litter of the forest floor where the soil is moist yet well-drained, and very rich in decaying organic material. In the garden good quality compost enriched with dry leaf matter and a dressing of bone meal would be ideal. If your soil does not drain well washed river sand can be incorporated. Slightly acidic soil is best as plants grown in alkaline soil may exhibit iron deficiency in the form of yellowing to white leaves. Potted plants will do well in a mixture of equal parts potting soil, fine wood mulch, and peat moss.

These perennial plants will arise every year from the rhizomes, with new stems developing after the old plant has finished flowering, creating a continuous display of flowers over the years.

In the garden they can be grown in full sun or semi-shade locations, but ensure that they receive sufficient sunshine to bloom well. In nature they make large colonies in bright clearings in the forest and most species require at least 6 hours of direct sunlight a day, or full morning sun to flower profusely. Plants grown in too much shade usually grow taller, with lush foliage and fewer flowers. Heliconia pendula and Heliconia stricta 'Carli's Sharonii' are two exceptions who enjoy shade. 

Established clumps thrive on frequent tropical showers, and in the garden the soil should never be allowed to dry out completely. Some species such as Heliconia standleyi and Heliconia densiflora 'Fireflash' can even adapt to growing completely in water.

To flower profusely heliconias need fertilising in spring, and every two months thereafter until autumn using bone meal and a balanced slow release fertiliser. Mulch around their roots regularly, and to keep the clumps neat it is necessary to remove the spent flowering stems regularly by chopping them off close to the ground.

Heliconia carabea purpurea Image by ASSY from PixabayHeliconia carabea purpurea Image by ASSY from PixabayPropagation:

Because the plants grow and propagate from underground rhizomes, if you already have them in your garden or wish to take a piece from a friend, this is easily done by carefully removing a small piece to start a new plant.

Heliconia are often sold commercially in the form of rhizome segments, and these should be dipped in a diluted fungicide solution before being planted in free-draining soil. A mixture of perlite, vermiculite, and sterilised potting soil is ideal.

Make sure that the rhizome is not planted too deep, but at the same level at which the plant was originally growing in soil. The planting depth can be determined by markings on the rhizome itself. After planting, the tip of the stalks where the pseudostems (A false stem made of the rolled bases of leaves) were cut from should be wrapped in plastic and secured with a rubber band. This helps to seal moisture within the rhizome and ensures that water does not enter the stems and cause rotting.

Seeds can be difficult, with a long germination period, so follow the instructions below. Because the seed coat is thick, before planting the seeds should be scarified with sandpaper till the endosperm is just reached. This allows water to enter the seed more quickly, thus shortening the germination period.

The seed requires soaking for two to three days in water and should be sown 2 to 5mm deep in well-drained damp seedling compost. Keep well-watered and at a temperature of 30°C until germination occurs after a couple of months. Once germinated, to get them growing strongly, the seedlings will need a temperature of 30°C by day and 18 to 22°C by night, combined with good sunlight.

Heliconia latispata 'Orange Giro' Image courtesy PixabayHeliconia latispata 'Orange Giro' Image courtesy PixabayProblems, Pests & Diseases:

If cultivated correctly in the garden heliconias do not suffer from many pests or diseases.

The leaves, roots, and rhizomes of these plants are prey to several plant diseases. Heliconia leaf diseases, in particular, are very common but rarely do lasting harm.

Curling leaves are often caused by a variety of fungi. There are many fungal diseases that cause leaf spots, yellowed edges, curled and distorted leaves, and dropped leaves once the disease has advanced. Most of these are soil borne and can be avoided by watering under the leaves and avoiding water splash. Use fungicides to combat these diseases.

The bacterial wilt caused by Pseudomonas solanacearum also causes heliconia leaf curling and wilting as well as a condition called “firing”, where the leaf edges turn brown. It is very contagious and in areas where it has affected plants the bacteria will remain in the soil, so further planting is not recommended.

Since heliconia are started from rhizome fragments, unhealthy pieces can harbour disease. Always inspect rhizomes before purchasing and planting.

Many fungi cause diseases on the rhizomes, causing rots of varying degrees. A few fungi organisms cause rot within the first few months while others take several years for disease symptoms to appear. In all cases, the plant declines and eventually dies. It is hard to diagnose the cause unless you dig up the plant, exposing the roots and rhizomes to scrutiny. You can prevent such diseases by washing rhizomes prior to planting in a 10% solution of bleach to water.

Root nematodes live in soil and feed on the roots of many species of plants, but are too small to be seen by the naked eye. Several of these tiny roundworms cause heliconia plant diseases. Roots become swollen and develop lesions and knots. This results in nutrient and water uptake interruption leading to yellow leaves, curling, wilting, and overall poor plant health. A hot water bath is the current suggested prevention. Dip rhizomes in hot water 50°C for 15 minutes and then immediately dunk into a cold-water bath. In commercial production, soil fumigation is used but there are no products listed for the home gardener.

The most common pest is the mealy bug, found on the underside of the leaf.  It can also attack the flower bracts.

Warning:

We did not find Heliconia listed and poisonous but did find some references to it being listed as mildly toxic to cats. Also, be advised that the consumption of any plant material may cause vomiting and gastrointestinal upset for dogs and cats.

It is also always advisable to supervise small children at all times in the garden.

An allergy caused by plants is another important aspect every gardener should know, and Heliconia allergy is toxic and can cause a serious reaction.