To avoid creating problems, consider the following:
* Avoid placing plants that have invasive roots near buildings, paved areas, water features,
drains, and septic tanks (eg: eucalypts, ficus ).
* Don't use plants that have the potential to become weeds. This includes plants that seed
prolifically, are prone to sucker, or are rampant creepers (eg: wandering jew,
lantana, even jasmine).
* Consider how big each plant is likely to grow. You should allow sufficient space for future
growth. Avoid planting large trees in places where they will eventually create
problems (eg: shade out lawns or other plants, damage buildings).
* Don't use trees that are likely to drop branches (eg: many Eucalypts).
* Choose plants which are likely to be trouble free (ie. withstand local storms, pests &
diseases, or poor soils).
* Select plants suited to the tropics or subtropics. Many people become disheartened
when a beloved plant dies - when all too often it was a plant that had little chance surviving in the climate.
TAKE A SIMPLE APPROACH TO PLANTING
The best way to approach planting is often the simplest.
*Keep plants together in compatible groups. Keep foliage plants together, herbs together,
orchids together, or alternatively plants that require similar amounts of watering, or
similar amounts of shade.
*Let the fittest survive.
*Mass plant areas (ie. several of the one variety together) to form hedges or eye catching
displays.
*Be prepared to get rid of plants which don't work (either don't look good or don't grow
well). There's no harm in being ruthless.
*Use reliable plants that neighbours are growing successfully, unless you wish to
experiment. If so research the requirements of your plants well, or be prepared to lose a
few along the way.
PLANT ESTABLISHMENT METHODS
The hardest part of growing plants is getting them through the first year. After that, they are usually quite well established and can tolerate harsher conditions with little ill-effect. Watch for the following when plants are young:
*Drying out (because roots aren't deep into the natural soil where reserves of water can be
drawn on hot days).
*Attack by insects or animals eating the foliage.
*Attack by insects (eg grubs) and animals eating the roots.
*Transplant shock, where the plant may be damaged, particularly it's roots, during planting
stage, or immediately after due to poor environmental conditions (heavy winds, rain).
*Never plant during the hottest time of the day.
When establishing plants in a garden, it is best to nurture them through the establishment phase. This might involve providing protection and support and then gradually reducing this degree of support until that plant is mature enough to survive itself.
WAYS TO HELP PLANTS GET ESTABLISHED
* Trickle & Drip Irrigation
Trickle and drip irrigation systems are a simple, cost effective means of irrigation for many gardens. Such systems provide a reliable source of moisture to your plants. This helps both plant establishment and subsequent growth.
Advantages:
*Constant or timed supply of water as desired.
*Reasonably priced and easy to install.
*Parts are often easy to replace or repair.
*Water use is greatly reduced.
*Water can be supplied to the ground and not to foliage so there are fewer disease
problems (eg: mildews).
Disadvantages:
*Blocked nozzles can be a problem due to residues, or debris (e.g. soil) that might build
up.
*Nozzles and drippers need to be checked to make ensure they are still pointing in the
desired direction.
*Sometimes moisture on the foliage is desirable.
*Depositing water in one or two spots may not encourage root development in all
directions, making the plant less stable.
* Mulches
Mulches assist in plant establishment and subsequent plant growth. These include:
1) Reduced competition to your plants by reducing weed growth.
2) Conserving moisture in the plants root zone.
3) Organic mulches provide nutrients and humus to the soil as they decompose thereby
aiding plant nutrition and contributing to improved soil structure.
4) Acts as a buffer to sudden changes in soil temperature that may damage plant roots.
Mulching can be used to provide a layer of insulation between the soil and the hot air
above, helping conserve water and helping keep the plants roots cooler. (This
method of keeping roots cool can sometimes allow you to grow some plants in the
tropics which would otherwise be difficult in such climates).
5) Reduced erosion and compaction of top soil.
Mulches can be composed of inorganic materials (eg: rocks, gravel, synthetics, etc.) or organic materials (eg: newspaper, manures, compost, leaf litter, straw, sawdust etc.)
Mulches mainly come in two forms:
Mat mulches: flat sheets or layers of materials such as plastic, newspaper, carpet underlay, weed mats, etc.
Bulk mulches: quantities of loose material such as sawdusts, barks, leaf litter, grass cuttings, etc.
Bulk mulches are easy to place. They can also be easy to dislodge. Weed growth penetrates bulk mulches more readily than mat types. Bulk mulches tend to be cheaper or more readily available than mat mulches. Some mat types prevent good water penetration (eg: plastic, paper & cardboard). Mat types need to be secured down (ie. pegged to prevent them lifting). The type of mulch you use will depend on factors such as cost, availability, ease of transport and the situation in which it is to be used.
Mulches should be applied while or just after planting. Before mulching, kill or remove any non-desired, existing vegetation. This can be carried out by cultivation, hand weeding or by using weedicides. Mulches should be thick enough to provide a good cover of the underlying surface, but not too thick that it will smother your plants. Bulk mulches should be at least 5 7cm thick. If weeds are a problem, between 10 and 15 cm thick would be better. Aim to keep the mulch clear of the plant stems or trunks, particularly organic types of mulch.
Problems With Mulches
*Mulches that consist of wood or bark products (eg: sawdust, pine bark) will draw nitrogen
from the soil unless they are well composted before use. Addition of nitrogen fertilisers will
overcome this problem.
*Some mulch materials, particularly those with fine particles, can pack together creating a
barrier that repels water, and reducing the amount of water to the plant roots. A mixture of
mulch materials or, composting the material before use will reduce the likelihood of such
problems occurring.
*The barks and sawdusts of some trees such as Pinus sp. and Eucalyptus sp. can contain
materials that are toxic to other plants. Be careful if using fresh material derived from
these trees or any unknown source.
*Some mulch materials are very light and will easily blow away or be dislodged. Mix such
materials with heavier materials to reduce the likelihood of this occurring.
*Slits in mat type mulches for plantings should be as small as possible and slit edges
overlapped to reduce the likelihood of weeds becoming established around the base of
the plants.
*Some mulch products may encourage termites, cockroaches or other vermin.
TREE GUARDS
Tree guards in the tropics are used for three main reasons:
1) As protection against differing climatic conditions such as strong winds
2) As protection against grazing animals such as rabbits, sheep, cattle, etc.
3) As a barrier to prevent damage by machinery, for example mowers.
Types of Tree Guards
#Plastic Tubes
The most durable types are UV stabilised these should last for several years. In many
cases, plant growth is significantly enhanced as the tubes create a warm, moist
micro climate. Protection from frost, wind, and rabbits is excellent. It requires 3 4 stakes to
keep the tube upright. Plastic bags, shopping bags or old fertilizer bags can also be used
as an alternative, although these are not as long lasting or effective.
#Plastic Mesh
Durable guards which are available in both flexible and rigid forms.
Require pegs or stakes for support. Don't create a protected, humid environment like
plastic tubes.
#Plastic pipe
Flexible plastic pipe, 50 100 mm diameter x 500 mm length, can be placed around stems
of young frost sensitive plants (eg.fruit trees).
These should be removed after the danger of frost has passed, otherwise fungal problems may occur, as the pipe tends to keep the stem damp.
#Wire Mesh
Chicken wire tied to stakes or stapled to 3 4 pegs provides a barrier against grazing
animals.
#Hessian
Hessian bags or cloth need to be tied around 3 stakes. Provides good wind and sun
protection although not in the long term.
#Tyres
Old car tyres placed around seedlings can be an effective and cheap barrier against
rabbits and hares.
#Milk cartons
Useful for marking location of seedlings and providing limited protection against vermin,
frost, etc.
COMMON PROBLEMS
The following are some of the most common problems encountered by the home gardener in the tropics and subtropics.
*Plant growth and height. Check carefully before purchasing plants. Some subtropical
species become invasive when grown in tropical conditions. Some temperate species, if
capable of growing in the tropics, may also become weed-like and invasive.
*Weed Control. Mulch to control weeds, apply in thick measure for good control. Overuse
or misuse of chemicals in a garden can be worse than no chemical control at all, so
research your options.
*If plants are doing poorly in a certain area of the garden but quite well everywhere else,
look at the past history of that area. Possible chemical or nutrient imbalances that may
have occurred by design or mistake. The site may have a slightly different soil type or be
prone to flooding, etc.
*Beware of importing pests and diseases into your garden from outside. Buying in soil or
sickly plants should be avoided if possible.
*PLAN a garden this will involve considerations of where to put various species, what
species to use and what will be required to care for them.
*Frequent light watering in summer will cause roots of large trees to come to, or develop
at, the soil surface. This can lead to damaged paths, buildings and may result in poor
drought tolerance. Overwatering can damage plant health, soil structure, nutrient
availability, and cause still other problems such as fruit splitting, etc.
*Safety with plants. Don't plant large trees too close to power lines or buildings. The
maintenance of these trees in the future could become very high, and they may eventually
pose serious safety problems. Don't choose plants that are known to cause allergies or
may be poisonous, particularly if children will visit your garden.
*The high growth rate in the tropics seems to wear the plants out - many plants have a
short life-span in the tropics.
*High growth rates require additional watering and fertilisers to keep the plants healthy
under those forced growth conditions, compared to similar plants grown in temperate
situations.
CONTAINER GROWING & GARDENING
Pot plants and container gardening can be a great way to add a new dimension to your garden. Consider the following points:
* Plants grown in containers can be moved around for different effects, creating a
constantly changing, dynamic garden.
* Some plants look good at certain times of the year, but not at others. When grown in
containers, such plants can be shown in a prominent position when they are at their best,
and hidden when they don't look their best.
* There may be cases where you want to grow a plant that would not tolerate your soil -
the growing media in your pot will overcome this.
* Vigorous plants can be controlled to some extent by containerising them.
* Many tropical plants look wonderful in pots when brought indoors for special events,
particularly when in flower (eg. heliconias).
Points to look out for when growing plants in containers in the tropics:
* Potting media tends to break down more quickly in tropical areas than in temperate
climates. This is because most potting mixes have an high organic matter content. As a
result repotting will need to be more frequent.
* Climatic conditions (e.g. heat, day length), vigorous growth and quick drainage
characteristics of potting media, mean that very regular watering and fertilising is required
during active growth seasons.
* Do not use saucers under pots as this may lead to root rots and increased mosquito
population (many human diseases are spread by mosquitoes).
* Do not add earthworms to the pots, nor allow other insects or animals to live in the
potting mix.
When You Go Away
In wetter months, you may find placing your containerised plants in a sheltered position is needed. In drier months you may be advised to do one of the following:
* Sit the pot in a trough, bath or other container with water (Do not immerse more than the
bottom one third of the soil).
* Install a trickle irrigation system with drippers to each pot (place this on a timer
mechanism so it switches on each day for a period).
* Put a slow watering bag on each container plant (ie. A bag filled with water with a dripper
tube releasing a very slow drip of water from the bag to the plant).
* Get your neighbours to keep a regular check on your plants.( It is important that your neighbours are reliable, and quite happy to do that for you.)
Problems With Containerised Plants
* Be sure to choose the right size pot for the plant. Large plants in small pots can readily
fall over, and will struggle to obtain sufficient water and nutrients from the growing media.
* Choose a growing media that has sufficient weight to prevent the plant from falling over
as it grows larger. Many potting mixes contain light weight ingredients such as perlite. If
there are a lot of such ingredients in the potting mix then there will be insufficient weight
in the container to counterbalance the weight of the plant's foliage as it grows.
* If potting mixes dry out too rapidly, then repot with a mix that retains more water, but be
careful not to choose one that holds too much moisture.
* Choose containers that have reasonable drainage to prevent waterlogging, but don't dry
out too quickly (e.g. unglazed ceramics, slatted timber containers, excess drainage
holes).
* For plants that are prone to rotting when dormant (e.g. some bulbs and herbaceous
plants), simply turn containers on their sides to prevent water getting into the containers,
or place them in an area where watering is minimised.
* If plants are getting tall and leggy, then the containers may need to be spaced further
apart to allow for increased light penetration.
POTTING UP PLANTS
All plants growing in containers, small or large, need potting up periodically, regardless of the size or type of container. Potting mix will compact over time, making watering more difficult and both drainage and aeration poorer. Pot up plants as follows:
1. Before removing a plant from an old container for potting up, water it thoroughly. If the
plant is dry it is best to immerse the old pot completely in a tub of water. (A wet root ball
will come out of an old pot far easier than a dry one).
2. If there is a tight mass of roots on the outside of the root ball, you should loosen those
roots and break away 10 20% of the old potting mix before repotting.
3. Place some quality potting mix in the bottom of the new container.
4. Place the plant into the new container and fill around it with new potting mix.
5. Water thoroughly then allow to drain.
