Plants Care

PLANT HEALTH NOTES

 

Why No Fruits On My Tree?

Basic Plant Care for Foliage & Flowering Plants

A Guide to Plant Fertilisers and User

Diseases of Roses in the Tropics

Pests of Roses in the Tropics

What is pH?

Plant Growth Requirements

 

Why No Fruits On My Tree?

 

If you look around the home gardens in Singapore, you would have noticed that many boast of fruit trees such as durian, mango, guava, papaya, rambutan, chiku ect. But the frustration comes when trees do not bear furits when they are mature? Here are some possible answers & guidelines to allevate your frustration.

Fertillising
In general, most tropical fruit trees will thrive in loamy soils that are well-drained. Poorly drained soils wil underlying hardpans limit the area in which the roots can develop and result in poor tree growth & yields. Fertillising trees at the proper time & with the correct nutrients is important. Here are some rules of thumb guidelines to follow for fertilising fruit trees: 

* Adjust the soil pH (acidity/alkalinity) to neutral 6.5 - 7.0 before you plant. Get a soil analysis to determine the adjustment needed. Our soils are generally acidic. 

* Incorporate organic matter or manure (aged animal dung) into the planting hole to improve soil condition and encourage new root growth. 

* During the first year after transplanting fertilise the sapling with about 500g of dried chicken manure & about 200g of chemical fertiliser 15:15:15 (NPK) monthly for vigorous growth. A guide for fertilising programme for the common fruit trees is given below. 

* Chemical ferilisers chould be applied by broadcasting or spreading evenly over the entire root zone. i.e. area under the plant's canopy & about 30cm from trunk. 

* Rake lightly the fertilisers into the top soil & then water in. 

* Over-fertilisation may encourage vegetative growth & litle fruiting. On the other hand, under-fertilisation retards growth & fruiting too. A regular & balanced fertilisation programme is necessary.



Fertilising Guide for Fruit Trees

Common Fruit Tree

Age (yrs)

Amt. of fertiliser grams/plant

Amt. of chicken manure kg/plant

Durian
1st yr (15:15:15) > 4th yr 
(12:12:17:2+TE)
(10:8:18:2+TE)


1 - 2
3 - 4
5 - 8


250g/3 mths
500g/3 mths
1 - 2kg/3 mths


2.5kg/2 mth
5kg / 2 mths
10kg /2 mths

Mango / Rambutan
1st yr (15:15:15) > 2nd yr 
(12:12:17:2+TE)
(10:8:18:2+TE)


1 - 2
3 - 4
5 - 8


250g/3 mths
500g/3 mths
1 - 2kg/3 mths


2.5kg/2 mth
5kg / 2 mths
10kg /2 mths

Guava
1st yr (15:15:15) > 2nd yr 
(12:12:17:2+TE)
(10:8:18:2+TE)


1 - 2
3 - 4
5 - 6


250g/3 mths
500g/3 mths
1 - 2kg/3 mths


2.5kg/2 mth
5kg / 2 mths
5kg /2 mths

Papaya
1st yr (15:15:15) > 2nd yr 
(12:12:17:2+TE)
(10:8:18:2+TE)


< 1 yr
1 - 2


45g/3 mths
45g/3 mths


2kg/2 mths
9kg/2 mths

Chiku
1st yr (15:15:15) > 2nd yr 
(12:12:17:2+TE)
(10:8:18:2+TE)


2 - 3


700g-800g/3 mths

2.5kg/2 mths

 

Maturity & Sex
Your fruit tree normally will begin to flower & bear fruit soon after it ahs biologically matured. The ages (from planting) when trees can be expected to bear fruit are as follows:

Varity

Age (yrs)

Grafted Durain

5 - 6

Grafted Mango, Guava, Starfruit,
Grafted Rambutan

2 - 3

Papaya

6 mths - 1

Chhiku

3 - 5

 

Tree Health
Pest prolems involving insects & diseases if not detected early & managed can influence fruit production & weaken a fruit tree's overall health. Newly emerged flowers should be sprayed with a mixture of benomyl & trichlorfon weekly & continued until the fruits are well formed to prevent flower & fruit anthracnose diseases attacks. Fruits like jackfruit, papaya, mango, guava & starfruit may be wrapped with paper to protect them from fruit flies or birds. Stop pesticide applications at least 10 - 14 days before harvest for consumption. For fruit flies, spot spraying with protein hydrolysate baits mixed with malathion is a viable alternative.

 

Climate & Weather
In Singapore it is often observed that fruit seasons usually correspond with the occurrence of dry weather especially seasonal bearing fruit trees.

* Mangoes require a distinct dry season. Sudden heavy showers can cause flower & fruit drop. Some fruit trees are very sensitive to micro-climate change that affects flowering & fruiting.

 

Pollination
Most fruit trees need to be pollinated. Pollination is affected by wet weather & some insect activity. without sufficient pollination, trees may blossom abundantly but will not come to fruit.

 

Blenning Bearing
Some fruit trees produce a heavy crop one year & sparsely the next. Biennial bearing is difficult to alter or correct. However, you can induce a return to yearly thinning (of fruits) during the year when the trees are producing profusely.

 

Culture Practices
Fruit trees need full sun & adequate space for root system development & fruiting. Water fruit trees deeply to keep soil moist but well drained. Pruning after harvest is important to remove dead & dying branches, old fruits & to improve ventilation & light penetration. Trees which flower & fruit on new shoots e,g. rambutan have to be pruned after each fruiting seaon to encourage production of new shoots. Remove rotten fruits & leaves from tree bases as these may harbour pests & diseases.

 

Additional Information
* Spray application of potassium nitrate (KNO3) at 10g per litre of water could induce flowering of fruit trees.

* Chopping the bark of a tree (shock treatment) sometimes induce it to flower. But open wounds invite baterial/fungal infections. Paint over with wound dressing.

 

Basic Plant Care for Foliage & Flowering Plants

 

The Garden City campaign brought about a lot of green foliage and flowering plants to the housing estates, gardens, parks, offices & our homes. With that came a large variety of foliage plants with different requirements.

The Plant Health Centre in our routine surveillance of plant health problems reports below some of the common problems encountered in our plant landscapes.

 

Soil Condition
One of the most important ingredient for healthy plant growth is the right soil type.

In general, the soil used in garden landscapes is of a high clay content. Heavy soil becomes sticky when wet and hard when dry restricting root growth. Water drain off slowly resulting in poor mamnaged properly, it is easy to over-water causing the roots to rot away, or drowning in water as a result of lack of oxygen.

Soil for planting should consistof equal parts of peat, coarse sane and soil. The soil mix should be of a friable texture, allowing water drainage while retaining some moisture. Different groups of plants require slightly different planting mixes. For plants that require a moist mix e.g. Heliconia species, increase the amount of peat as it will help to retain moisture for the plants. For clay soil amendment, addition of organic matter and sand should help tp improve the soil texture.

Our findings showed that most of the soil is acidic i.e. with a soil pH ranging 4 - 6. pH is a measure of soil acidity or alkalinity. Many of the soil reactions (e.g. release of nutrients bound to soil particles) depends on the pH. The soil pH determines the amount of nutrients available for plant use. If the pH is either too low or too high, nutrients help by soil are not released. And no matter how frequent and how much the plants are fertilised, the plants will still suffer from mineral deficiency.

Most plants will grow in soils with a pH of 5.5 to 7.5. Some plants prefer an acidic soil while other can tolerate alkaline conditions. Plants growing in acid soils are often stunted and off-colour. Their roots are sparse and reduced.

The pH of acid soil can be corrected by the addition of lime or dolomite to the soil. In addition to raising the soil pH, the lime supplies magnesium and calcium, nutrients that are usually deficient in acidic soils. Do not over lime acid soils either, because when the soil pH is too high, the availability of some nutrients e.g. iron, manganese, boron, copper & zinc may be decreased. To prevent over-liming, the pH needs to be checked after addition of lime amendments.

 

Fertilisers
A well-balanced supply of nutrients will ensure that plants thrive and produce flowers. The common type of fertilisers used are the inorganic granules. Sometimes, organic fertilisers i.e. processed animal dung are used. Organic fertilisers are ideal in the long term as the nutrients will be slowly broken down by microorgansims & made available for uptake.

If an acute lack of nutrients is diagnosed, a synthetic chemical fertiliser should be used as the nutrients can immediately be available for absorption by the plant. Chemical fertilises used should preferably be supplemented occasionally with formulas containing trace elements like boron, copperm iron, manganese and sinc. Very often, plants were found to be deficient in these trace elements especially Heliconia spp. & palms.

 

Disease & Pest Probelms
Healthy, well-maintained plants grow sturdily and are less likely to develop growth problems or to be attacked by pests or diseases. Unhealthy plants are usually the result of poor cultivation, wrong treatment or simply neglect - actual pests or diseases are, in fact, rarely to blame. However, when they do occur, correct diagnosis of disease & pest is necessary for effective control.

So far, most of the disease problems encountered are due to fungal infection e.g. leaf spots & blights caused by Colletotrichum gloeosporioides, Phomopsisspp. etc. Fungal diseases usually occur because the plants had been over-watered, or water has lodged in the leaf axils causing conditions for fungi to thrive. Stem, root rots & wilts are common in poorly drained areas after a rainy season. Always remove diseased parts as soon as you see them and apply the correct fungicide treatment to protect healthy parts of plants.

Insect pests are also common in plants. Infesttion with scale insects, aphids, leaf miners & mealybugs are fairly common. All identified pest problems should be treated as soon as possible using the appropriate type of insecticides.

Pest & Disease control tips are available in our plant health pamphlet #14 - "Pest Management Measures for Control of Garden Pests & Diseases".

Management committees of condominiums & estates can approach us if they would like to participate in our on-going plant health survey.

 

A Guide to Plant Fertilisers and Use

Soils in the tropics are generally low in essential elements necessary for plant growth. Fertilisers are applied to the soil to increase fertility so that plants can grow vigorously and reproduce.

 

Fertiliser Types
Fertilisers are of 2 types - organic and inorganic. 

Organic fertilisers are from decaying plant and animal matter.

Orangic fertilisers available locally are:- 
*Fish emulsion 
*Seaweed 
Manure (cow, poultry, guano) 
*Soybean and groundnut cake 
*Compost

Inorganic fertilisers are from minerals of the earth's crust or made wia chemical processes. 

Inorganic fertilisers available locally are:- 
* Ammonium sulphate, nitrate and phosphate 
* Muriate of potash 
* Potassium nitrate and sulphate 
* Kesereite 
* Superphosphate 
* Urea 
* Compund fertilisers e.g Nitrophoska 
* Foliar fertilisers e.g Foliar 63

 

The Essential Elements
Plants obtain carbon, hydrogen and oxygen from water, air and sunlight to make food for growth. In addition, they require the elements of nitrogen (N), phosphorus (P), potassium (K), sulphur (S), calcium (Ca) and magnesium (Mg) without which the plants will fail to grow and reproduce. These elements cannot be substituted as they are essential to metabolic processes for plant growth.

 

Functions of N, P and K

N :

promotes vegetative growth and production of lush foliage.

P :

promotes the formation of lateral and fibrous roots to increase absorption of nutrients, promotes flowering and increases strength of plant stems.

K :

promotes formation and enlargement of fruits, increases efficiency of leaves to make sugars and starch and increases plants' resistance to diseases.

 

The Trace Elements
Other elements are required by the plants in minute quantities for normal growth. They are termed "trace" or "minor" elements or "micronutrients". Examples are copper (Cu), manganese (Mn), zinc (Zn), iron (Fe), boron (B) and molybednum (Mo).

 

 

Diseases of Roses in the Tropics

Roses fall easily to the following diseases:-


The initial symptoms of powdrey mildew caused by the fungi, Spherotheca spp. are small patches greyish white powder, usually near the top of the young growing shoots and succulent young leaves. As the disease progresses, more matured leaves and flower buds are affected. The leaves curl. distort and fail to develop. Photosynthetic efficiency is greatly reduced and the plants becme weak and susceptile to other diseases such as black spots. Control with weekly sprays of fungicides such as Benomyl or Triforine. 

Black spots is a common rose disease caused by the fungus Diplocarpon rosae. These attack the leaves, forminng circular black or dark brown patches with surrounding yellow leaf tissues. The disease can extend to young stems. The disease can result in complete defoliation of the plant. Each leaf that falls carries with it millions of spores. Thus all infected leaves and stems must be removed and burnt and reduce water splashing. Spray plants and leaf litter with Benomyl or Metalaxyl fugicides to prevent disease spread and accumulation. 

Black mildews, commonly known as "sooty moulds" are caused by the fungiMeliola spp. They grow on the surface of the leaves and stems are often associated with insect infestations and form a black velvety covering. Their presence mainly make the plant unsightly. Minor infections do not cause much damage and control is often not necessary. They can also be removed by washing off with mild detergent. Severe infections may be controlled with general fungicide sprays. 

The fungi, ALteraria spp., Colletrotrichum spp. and Cercospora spp. caused leaf spots. Rainy periods favour Alternaria infections. The leaves become brittle and the colour changes from yellow brown to dark brown. The spots enlarge and concentric rings become visible. Flower buds and flowers become susceptible if moist and humid conditions persists. 

Cercospora spp. form circular spots of about 1-5 mm in diameter showing dull grey, tan or pale brown centres. These spots join to form irregular purple to reddish brown spots. Severe infestations caused defoliation. These fungi can be controlled using Carbendazin, Captan, Maneb or Zineb. 

Diebacks and Cankes are caused by several parasitic fungi (Diaporthe spp.,Leptosphaeria spp., Cylindrocladium spp. and Glomerella cingulata) that usually enters plant through wounds, stems or graft tissues. Lesions are formed in the woody tissues as red, brown or purple spots often with purple margins. These enlarge gridling the canes caused death to parts above the cankers - thus shoot diebacks. In developed cankers small black fruiting bodies can be seen.Infected canker at a node woth shears dipped in alcohol after each cut. The cut area can be painted with pruning paint or fungicide paste. 

Rose masaic is a common viral disease. Plants infected by the rose masaic virus exhibit symptoms of yellow "netlines" of the leaves, ring sots and mottling. Flower production is reduced and quality is poor. The disease can be contained by removing infected plants and using plants that are indexed virus free for propagation. Other virus disease are leaf rosettes, leaf curls and flower colour breaks.

 

 

Pests of Roses in the Tropics

The rose plant, Rosa spp. belongs to the family Rosaceae. There are five main groups of roses. They are hybrid tea roses, floribunda roses, miniatures, climbers and potpourris, cure for ills, a symbol of beauty as well as a popular bush for the gardens. They usually need quite a bit of care as weak plants are easy prey to several pests and diseases.


Aphids are small (less than 3 mm long), have long antennae, are mainly green in colour but can be yellow, pink, red, grey, black or brown. Most aphids are wingless. However, when temperature is nt suitable or over-crowding takes place, some spieces can form wigns and move to new areas. 

When a plant is attacked by a large population of aphids, damage such as stunted growth, wilted leaves, drying branches, stunted thorns, curled, yellowed or downward cupped foliage result. The young leaves and tender shoots are attacked first. Aphids feedon the sap from plants and excrete it as a clear, sticky, sweet substance, called honeydew. The honeydew also attracts the growth of a black cooty mould. Some species of aphids are known to transmit virus diseases to the host plant upon which they feed. 

The aphid undergoes three life stages: egg, nymph and adult. Aphid populations reach high numbers very quickly, due to a high reproductive rate. Females can give birth to youngs without mating and a large percentage of the offsrpings are females. 

Spider mites can be red, orange or yellow coloured with eight legs. These mites may habe two black spots on top. They are small, but visible. The eggs vary from transparent and colourless to opaque straw yellow. The mites feed on plant sap. 

If spider mites infest your rosesm you will begin to notice a dull appearance (bronzing) to the leaves. The undersides will feel "sandy" or rough. Fine webbing will appear on the udersides of leaves and in leaf axils. Leaves will begin to lose their colour and become dry and lifeless. The leaves soon dry up and die. After a heavy attack, an entire plant may become yellowed, bronzed or killed completely. The mites may spin so much webbing over the plant that it becomes entirely covered. Spider mites infestations is prevalent during the hot and dry seasons. 

Scale insects are small, piercing and sucking insects that often go unnoticed. The adult forms can be attacked to leaves, petioles and stems. They suck plant juices and caused plants to loose vigour. 

The first signs may be yellowing or wilting of leaves that may eventually drop. Leaves may also be covered with a sticky honeydew inviting sooty mould growth. Closer inspection will reveal small cottony (soft scales) or dome shaped shells (armoured scales) attached to stems and leaves. When peeled off, they are hollow underneath or filled with eggs. 

Thrips are small (5 mm) feather-like winged, pale-coloured insects. They are rarely seen because of their small size and hiding habit. The insects feed by scraping the surface of the plant parts and sucking out the plant juices. Flowers or leaves my develop silvery streaks. Heavily infested leaves appear brownish or silvery and growing points may become distorted. Infected buds do not develop fully. Some species of thrips leave sooty spots of black fecal matter on the leaves. THrips also vector vrial diseases. Female thrips lay their lay eggs year round in tiny slits cut into the surface of leaves, flowers and stems. The eggs can be laid at any time of the year and hatch within a few days in warm conditions. The young called nymphs, are cream to pale green and only visible with magnification. They feed for 7-14 days. Full grown nymphs, in most species, drop off the plant to the soil where they burrow down and pupate. Winged adults emerged to complete the cycle. 

Indicator traps such as light blue sticky cards suspended within two meters above the plants can be used as traps for thrips. Winged adults caught ont he card indicate and reduced the presence of thrips. 

Slugs and Beetles from their feeding will make holes in the leaves. These are usually active at night. Hand pick to remove these pests. Slugs may be killed by dropping them unto a can of concentrated salt solution. 

Pest Management Measures
1. Remove colonies of the insect by pruning off and disposing the plant tips, stems or leaves that are heavily infested with aphids, mites or scales. It is also possible to knock mites off by spraying with strong stream of water particularly on the undersides of leaves. Scales may be rubbed off by hand or with a discarded toothbrush or with cotton swab soaked in 70% alcohol or methylated spirit. 

2. User insecticidal soap. Insecticidal soaps which are considered non toxic to humans and pets give good control. Be sure that flowers and growing tips are well covered with the spray. Frequent sprays may be needed until the problem is under control. A homemade insecticidal soap using a 1.5-2% solution of dish washing soap can be also used. But for uniform performance and to avoid damage to plants, specially formulated insecticidal soaps are preferred. Certain plants are sensitive to soap application. 

3. User superior horticultural oil sprays. Highly refined oils sold as horticultural oils will also conrol these pests especially scales. The oil suffocates the insects, usually without damage to the plants and beneficial insects. Follow label directios to avoid damage to some plants that may be sensitive. 

4. User chemical insecticides - pyrethin or deltamethrin for aphids, miticidal sulphur for mites and permethrin for thrips.

 

 

What is pH?

pH is a measure of how acidic or alkaline the soil or water is. The pH scale ranges from 0 to 14. A pH values less than 7 indicates an acidic soil or water. A pH value above 7 indicated alkaline soil or water.


pH & Plant Growth
Plants vary in their reactions to soil pH. Generally, plants grow well in soil of pH 5.0 to 7.5. Deviations from this range will affect the availability of plant nutrients such as phosphorus, copper and zinc in soils or substrates to the plants. In tropical zones, calcium phosphorus, potassium and magnesium are generally deficient in acidic soils while aluminium, managanese and iron may be present in toxic amounts. 

Plants grown under adverse pH conditions may be stunted, weak and are more prone to disease attacks. Their leaves may yellowed, develop tip burn or lack shine. 

Correcting Soil pH
Liming, the application of calcium carbonate, dolomite or ground shells will neutralise acidic soils to increase the pH. The addition of organic matter, humic acid or citire acid may correct alkaline soils. 

What is salt content?
The term salt as applied to soil refers to soluble minerals of the elements of sodium(Na), potassium(K), calcium(Ca), magnesium(Mg), phosphorus(P) as well as other trace elements. 

Sources of salts
Salts come from the weathering of the earth's crusts, receding sea water or accumulation from over application of fertilizers. These salts are usually released in a soluble form. Soil therefore may contain salts of chlorides, sulphates and carbonates. 

Scale insects are small, piercing and sucking insects that often go unnoticed. The adult forms can be attacked to leaves, petioles and stems. They suck plant juices and caused plants to loose vigour. 

Effects of excessive salts on plants
High salt content in soil will cause the plants to be scorched with leaf edge burns and plant wilt. In severe cases, the plants may dry up and even die. It also affects microbial activities ad soil properties. 

Ways to improve soil of high salt content
It can be improved by adding water to the soil and allowing it to soak through the soil to drain or leach away the salts. 

If the soil contains too much sodium salts, calcium sulfate may be applied by followed by leaching with water. The sodium salts will be replaced and leached out.

 

 

Plant Growth Requirements

Plants are adapted to their natural environment. WHen we bring them into the home, we must provide them with suitable conditions to maintain their healthy growth. Plants have specific needs for soil, light, water, mierals, air and an optimal temperature range.


Soil
Conventional gardening involves rooting plants in pots filled with soil. The soil type used greatly influences the growth of the plants. The soil basically provides anchorage as well as holding and releasing nutrients to the plants. In order to fulfil these basic functions, the root system must be healthy; and this is determined by the soil "content" which is the soil mixture we put into the pot. The potting mixture must be suitable for each specific plant in order to support healthy growth. The potting mixture is prepared, based on the ratio of three components: 
a) loamy soil (which is friable in texture) 
b) organic matter (eg peat moss, well rotted chicken dung, etc) 
c) washed river sand (fine to coarse particles) 

There are mainly 3 potting mixtures that can be formulated: 
1. standard  - 3 : 2 : 1 
2. sandy      - 1 : 2 : 3 
3. moist      - 1 : 3 : 0 

For example, the standard potting mix can be made by mixing of loamy soil, 2 parts of peat moss and 1 part of sand. The standard potting mix is recommended for most house plants. The sandy potting mix is most appropriate for the cacti. The moist potting mix is for humidity-loving plants like the ferns. 

Light
Plants require light as a primary energy source. In the process termed photosynthesis. light is harnessed to convert carbon dioxide and water into carbonhydrates, an efficient energy reserve to drive biochemical reactions necessary for growth. However, plants have different levels of requirement and tolerance for light. The amateur gardener can use the following as a guide on optimal light requirements. 

1. Sun-loving plants. These are plants that can withstand direct sun. They will grow well in bright areas of the home like balcony. Examples are cacti and succulents, Bougainvillea, Adenium, etc 

2. Semi-shade plants. Flowering plants rarely produce blooms in this situation but many foliage plants retain their vivde colours. Most ferns can be adapt to shaded conditions such as in the kitchens and living rooms. 

Water
Plants in the garden receive rainfall, but a pot plant relies only on watering by the gardener. Though water requirements of plant species vary, a rough guide on watering can be used. 

1. Fleshy plants such as the Mother-in-law's Tongue (Sansevieria), Aloe veraand cacti which store water in their leaves or/and stems, can withstand a few weeks without watering, especially in the cooler periods of the year. 

2. Some plants have fine hairs or a waxy cuticle on the leaves. For example, the IndiaRubber (Ficus elastica) has waxy leaves. Such features reduce trannspiration from leaf surfaces, cutting down warer loss from the plant. These plants can tolerate moderate draught. 

3. Some plants have thin, delicate leaves. Examples are Fittonia and Maidenhair Fern (Adiantum raddianum). These plants tend to lose more water through transpiration, especially if they also have a large total leaf surface area. 

4. Plants in non-porous plastic pots require less water than those in clay pots which allows moisture to escape through the porous walls. 

5. Plants showing signs of active growth (sprouting new shoots/buds/flowers) need more water. 

Techniques of Watering
1. Most plants can be watered from the top, upon their foliage. Allow excess water to drain off. 

2. Do not water on foliage of species like Begonia rex, hairy plants such as Gloxinias and African Violets, or flowering plants in bloom. Water just within the rim of the pot or provide water from the bottom of the pot. In the latter method, stand the pot in a bowl of tepid water until the surface of the soil is moist, then remove and allow to drain. 

Do not over-water as it causes water-loggin of roots which can kill the plant. Between watering, allow the soil to dry to provide aeration to the roots. 

Mineral Requirements
Plants absorb minerals from the soil. These are essential for growth. For a potted plant dependent on limited soil, the supply of minerals has to be replenished with fertilizers. There are mainly two kinds of fertilizers, organic or inorganic. Organic fertilizers release their nutrients slowly over a long period of time, through decomposition. Examples include the animal dungs (chicken, goat, bird, etc). compost, fish meal, bone meal and many other. In their untreated state these slow release organic fertilizers emit foul odour and may be unpleasant to handle. However, in the market, there are a number of organic fertilizers that are well processed and devoid of foul smell. The inorganic fertilizers, more commonly referred it as chemical fertilizers, are quick acting and more convenient to use; the fertilizers can release their nutrients quickly for use by the plants. For home gardening, it is good to use the foliar-type chemical fertilizers which are commerically available in liquid or crystal form. We recommended chemical fertilizer for feeding. These fertilizers are commerically referred to as "NPK" fertilizers which carry labels giving the content of its nutrients, in the ration of N:P:K, ie, the percentage of nitrogen(N), phosphorus(P), potassium(K). Nitrogen is needed for lead growth. A foliage plant should be given fertilizers with a higher percentage of nitrogen. Potassium ad phosphorus are needed for flower formation as a mature flowering plant shoudl be fed with a fertilizer containing a higher percentage of potassium and phosphorus. Phosphorus is also important for healthy root growth. 

Whichever fertilizer is chosen, it is best to follow the instructions given by the manufacturer. Remember that overfeeding a plant with, especially a chemical fertilizer, can kill it.