Distance Education Course: Become a Tropical Plants Expert
- Learn to identify and grow different tropical plants
- Learn to use tropical plants in gardens, as indoor plants, container specimens, etc.
- Follow your passion, or work with tropical plants as a career
- A course for nurserymen, plant breeders, landscapers, gardeners, interior plantscapers, or anyone with an enthusiasm for tropicals.
Tips for Growing and Using Tropical Plants
Lush growth, vivid colours and a warmth in the air which makes anyone feel relaxed; these are what we strive for in a tropical garden. All too often though, we get uncomfortable sweltering heat, wilting plants and armies of insects that eat the garden faster than it grows. This book shows you how to get closer to the first of these options, and ways of overcoming those problems which are particular to gardens in warm climates.
TROPICAL AND SUB TROPICAL GARDENS
Before reading any further, you should decide what you want a garden for. Some people have a dream, an image of an "oasis" to escape the heat, or the problems of daily life. Others want a garden they can use, for entertaining, outdoor living, for children to play in or maybe even a place to keep a prized collection of plants. Whatever your purpose, it is important to plan. Planning never stops either, because a garden never stands still. Try to foresee what will happen in your garden in the future (eg. trees and shrubs which will die, areas that will gradually become more shaded), and plan changes to your garden accordingly.
TYPES OF GARDENS AND PLANTS
There are many different types of gardens. You might choose to have any of the following; or perhaps a garden which has aspects of more than one type.
FORMAL OR INFORMAL
Formal gardens are neat and tidy, the edges of paths and garden beds are usually very well defined, and the garden is often a symmetrical design (ie. one part of the garden is a mirror image of an adjacent part). Shrubs are often clipped to develop a specific shape as a hedge or trained against a wall.
Informal gardens are not always so neat, edges are often irregular shapes with plants spilling from beds onto lawns or paths. The overall affect is less manicured and if designed properly things do not look so unattractive or out of place even when maintenance is neglected for a period.
Gardens can have varying degrees of formality. Generally the most formal gardens are the most time consuming to maintain.
These try to recreate a natural environment. It is important that you choose a theme and stick to it otherwise the garden may look quite nice but be a meaningless assortment of plants. Many of the best native gardens are modelled on real bush examples (eg. An open woodland, a dense forest, rainforest, heathland or rockery).
DRY GARDENS (Xeriscapes)
A xeriscape is a garden which is developed for harsh dry conditions. It uses plants which tolerate drought and heat. (eg. Cactus and succulent garden, Desert garden, Australian Native Arid Zone Garden).
This is a garden which uses only natural materials in it's creation and maintenance. It is free of pesticides and artificial chemicals. Mulch and compost are used to feed plants, smother weeds and reduce the need for watering. Other natural techniques are used to minimize pests and diseases. Those problems which occur beyond this are simply tolerated in the knowledge that nature will eventually re-establish a balance.
Permaculture gardens are designed to produce things which can be used (eg. food, crafts, fuel, etc), and to create an environment which is protected from undesirable affects of nature (eg. extreme wind, heat, flood, etc). It doesn't really matter what a permaculture garden looks like, as long as it is functional, environmentally friendly and relatively low maintenance.
Cottage gardens originated in temperate climates, but the style has evolved and been adapted successfully in hotter places. These are low maintenance gardens, which mix a wide variety of flowers and other useful plants (including fruit and vegetables), creating a montage of colours and textures. They usually contain little or no lawn, lots of colour, a large variety of textures and colours, edible and scented plants, and a variety of traditional features such as trellis, wrought iron, picket fencing, cast iron furniture, statues, topiary, low hedges, sundials and birdbaths.
Companion planting is based on the idea that certain plants grow better in close proximity to other plants. (eg: Garlic planted under a peach tree will improve the performance of the peach by deterring the development of peach leaf curl, a disease which is very common on peaches). Companion planting works by using plants which either deter pests or disease, attract pests away from valuable plants, or contribute to the fertility and structure of the soil.
A spiral garden is a raised or sunken garden where the plantings form a spiral either rising up the mound or sinking into the depression. The spiral is delineated by a wall (stone, timber, masonry) which both serves to retain the earth on the slope and also to separate one area of garden bed from the adjacent area (which is at a higher or lower level).
Water which falls onto the highest point of the spiral will always tend to run down hill (in a spiral), collecting at the lowest point. The highest part of a spiral garden is generally the driest (hence is planted with plants which prefer drier conditions). The lowest point of a spiral (particularly in a sunken garden) is the wettest (hence is planted with plants tolerant of wet conditions, or preferring wet soil).
NO DIG GARDENS
In simple language, this type of garden is made by making garden beds using deep compost heaps on top of the ground. Plants are then planted straight into the top of these mounds. As they slowly rot down the mounds release a constant supply of nutrients to feed plants, and being raised above ground level they provide good drainage while the organic matter still retains ample water for the roots.
Japanese and Chinese gardens each have their own unique style, but both share similar principles. These gardens emphasise nature. Materials (plants, rocks, gravel, water etc) are used in a very natural way where harmony and tranquillity are primary aims. These gardens are much more common in cooler areas, but with a bit of perseverance, a garden with such a theme may be possible in the tropics.
MIDDLE EASTERN GARDEN
Typically formal and ornate, these gardens make extensive use of tiles and garden structures. Pergolas or other structures are often incorporated for shade, water is usually included for coolness, and the garden is often walled for security and privacy.
Walls create a sense of enclosure in a garden, and also create a protected environment, restricting air movement (ie. wind). In hot areas a walled garden may look great but must be designed carefully if it is to avoid becoming a heat trap.
There are 10 lessons in this course:
Introduction to Tropical Plants
What does the term "tropical" mean
What tropicals grow where you live?
Plant names/classification (scientific & common)
Species, hybrids, varieties and cultivars
Growing Tropical Plants in different climates; tropical, sub tropical, arid and temperate
Climatic Variations; seasons, mountains, savannahs, rainforest, coastal
Gardening for Warm Climates and Microclimates
Good and Bad News about Tropical Gardening
Heat Traps, Warming a Garden, Greenhouses
Plant Cultural Practices
Common Gardening Problems
Understanding soils, naming a soil, texture, pH, fertility, nutrition, feeding
Water and Plant Growth
Water deficiency and excess symptoms
Water Dynamics in a Soil
Planting and Plant Establishment Methods
Propagation,cutting, seed, propagating media
Potting Mixes, Potting up, Caring for young plants
Tropical Annuals, Perennials, Bulbous Plants, Bamboos & Lawns
Bamboos, Grasses and Grass Like Plants
Landscaping with Bamboos
Review of Bamboo species
Review of other herbaceous tropicals, including: Achmines, Agapanthus, Alocasia, Amorphophallus,Aristea, Babiana, Boophone, Brunsvigia, Caladium, Calaqthea, Calostemma,Clivia, Calocasia, Crinum, Crocosmia, Cyrtanthus, Dierama, Eucharis, Eucomis, Gladiolus, Gloriosa, Zephranthes, Hippeastrum, Hymenocallis, and many others
Turf Varieties for Warm and Hot Areas
Ornamental Gingers and Heliconias (and related plants)
Zingerbales; Musaceae (bananas), Strelitziaceae (bird of paradise), Lowiaceae, Heliconiaceae (heliconias), Zingiberaceae (gingers), Costaceae (costus), Cannaceae (cannas), Marantaceae (prayer plants
Cordylines, Palms & Cycads
Types of Palms; self cleaning, cleaning, solitary or clumping, fan or pinnate, etc
Review of many cultivated Palm Genera
Climbers, Shrubs and Trees
Review of many cultivated Tree and Shrub Genera
Review of many selected species characteristics
Conifers; culture, genera, species
Climbers; Allamanda, Antigonon, Aristolochia, Beaumontia, Bignonia, Bougainvillea, Campses, Ceropegia, Cissus, Clematis, Clerodendrum, Clitoria, Clytostoma, Combretum, Congea, Ficus, Hoya, Ipomea, Manettia, Mucuna, Pandorea, Philodendron, Scindapsis, Stephanotus, Thunbergia, Trachelospermum.
Orchids, Ferns, Aroids and Bromeliads
Types of Ferns; Fern Classification and families
Tropical Herbs, Vegetables and Fruit Bearing Plants
Growing Methods; organic, no dig, permaculture, Container Growing, Hydroponics, etc
Culture of Selected Vegetables in tropical and sub tropic conditions
Tea and Coffee
Tropical Fruit trees
Growing Tropical Plants outside the Tropics
Growing tropicals indoors
Growing in different climates and conditions.
Landscaping with Tropical Plants
Use of colour & texture
Planting a courtyard
Preparing sketch plans.
Each lesson culminates in an assignment which is submitted to the school, marked by the school's tutors and returned to you with any relevant suggestions, comments, and if necessary, extra reading.
Explain the nature and scope of tropical plants
Discuss cultural characteristics that are often peculiar to tropical plants
Describe the taxonomy and culture of a range of soft wooded tropical plants including annuals, perennials and bulbs.
Describe the taxonomy and culture of Heliconias and Gingers..
Describe the taxonomy and culture of Palms and Palm like tropicals.
Describe the taxonomy and culture of climber, tree and shrub tropical plants.
Describe the taxonomy and culture of Orchids, Ferns and Bromeliads.
Describe the taxonomy and culture of Herbs, Vegetables and Fruits in tropical conditions.
Tips for Growing Trees in a Tropical or Sub Tropical Garden
People frequently have more trouble with trees than any other part of the garden. If they like trees, they tend to plant too many trees too close together. If they don't like trees, they tend to plant too few. It is important to consider why you might need trees, and then choose the appropriate number, type and sizes to suit your requirements and the size of your garden.
Trees are used for the following reasons:
- A screen for wind - wind will go over or around very dense vegetation. Wind goes through, and is slowed by less dense plantings.
- A noise screen - don't expect a complete barrier to noise. Plants reduce volume, but they don't completely stop noise.
- A screen against fumes - if you are beside a major road or factory, trees are essential to keeping air quality reasonable in your backyard.
- To hide ugly views - canopies can cut out ugly views (e.g. tip sites, factories or unkempt neighbouring properties).
- To provide privacy - plant wherever people are going to be able to see in.
- To create a visual link with adjacent areas - if there is a treed area just outside of your property, plant some trees adjacent to those plantings, but on your property. This creates one clump of trees which starts on your property, then extends beyond the boundary, giving an illusion of your property being bigger than it actually is.
- To create an ecological link (corridor) with nearby areas - if you plant trees which supply food and shelter for nearby wildlife, you will find that wildlife will move into your property.
- To frame views - if you have a valuable distant view (e.g. mountains or the ocean), plant trees either side of the line of view to enhance and direct your attention towards that view.
- To provide features in the garden - large well-formed trees when planted alone in a lawn or amongst small plants will create an impression of grandeur which draws the eye. Smaller trees have the same effect when they provide a contrast in colour (i.e. in foliage of flower), or texture against whatever is around them.
- To provide shade - shade is important, to protect other plants, and to provide a more comfortable atmosphere for people. Too much shade can deter plant growth, restrict the movement of fresh air and lead to water problems (because the ground does not dry out).
Suggested Trees for Tropical Gardens
Araucaria heterophylla -8m or taller, Green foliage
Banksia integrifolia -10 to15m tall, Spiky foliage, Yellow brush like flowers
Bauhinia variegata -to 10m tall, Green foliage, Pink flowers
Brownea grandiceps to 5m tall, Weeping foliage, Red flowers
Callistemon viminalis -to 7m tall, Weeping foliage, Red bottlebrush flowers
Cananga odorata -to 15m, Semi-weeping, Lime flowers
Caesalpinia ferrea - to 8m, Deciduous foliage, Yellow flowers
Cassia fistula -to 6m tall, Deciduous, Yellow flowers
Casuarina glauca -to 15m, Fine needle like foliage, weeping habit, insignificant flowers.
Delonix regia -to 12m tall, Red-orange flowers
Dombeya wallichii -to 10m tall, Matte-green foliage, Pink-red flowers
Erythrina indica -to 8m, Orange flowers
Ficus benjamina -15m rall, spreading, Weeping glossy green foliage, Red fruits
Hibiscus tiliaceus to 7m tall, Green foliage, Yellow flowers
Jacaranda mimosifolia -15 to 18m tall, Fern like leaves, Purple flowers
Lagerstroemia indica 7 to 10m tall, Deciduous, Showy flowers of varying colours.
Mangifera indica -to 20m, Foliage with red tips when young, Scented white flowers
Plumeria rubra, (P. obtusa) -5 to 7m tall, Green foliage, Flowers can be white, yellow, red or other colours
Spathodea campanulata to 8m, Orange/red flowers
WHAT IS SO UNIQUE ABOUT WARM CLIMATES
Warm climates all have one thing in
common; they get hot during the day. Apart from this they can vary a
great deal from place to place. There are places in the sub tropics
which can record very cold temperatures at night (eg. Desert areas and
high mountains); and there are places which are extremely dry as well as
places which are very wet.
Generally light levels are higher, and
day lengths don't shorten or lengthen to the same extremes that they do
in cooler climates. Wherever there is water in a hot climate, humidity
can increase. Humidity can be good for some plants and bad for others;
and will be greater in wet climates, after rainfall, near lakes and
canals, in irrigated areas or around plants which are mulched with moist
organic materials. Storms can be more fierce in the tropics. Rain
often falls heavier, winds blow stronger, and plants can be badly
damaged by cyclonic conditions. Summer, Autumn, Winter and Spring don't
seem so obvious in warmer climates. There are really only two, more
obvious seasons: the wet and the dry. All of these factors can have
serious affects upon the way some plants perform.
WHAT CAN YOU GROW EASILY?
The best way to know what grows well in
your locality is to look around at other gardens in the area, and note
what other people are growing most successfully.
Many plants grow much faster and easier
in hot climates than in temperate areas; but often the diseases, pests
and weeds will also develop faster. Some plants listed in this book can
in some areas grow so well that they become invasive and turn into
weeds. The easiest plants to grow are not always the most vigorous.
Remember vigorous plants may require
frequent cutting back. Look for plants which are generally resistant to
pests and diseases, tolerate adverse conditions, but do not grow so
vigorously that they become invasive.