Hi, my name's Linda and I'm here to help you learn how to care for plants and shrubs.

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What is pruning?

Hi, so you're not too sure what pruning is? Well let's take a look at it.

For pruning to be carried out in a professional way you need to start by looking at the whole plant to see which parts of the plant need to be cut back to make the plant look good, grow better and produce better flowers or fruit.

The parts that may need to be cut back could include the roots, branches, shoots or buds, fruit or flowers. Pruning needs to be done at the right time of the year for the particular plant species and should be carried out in a way that will not unduly damage or harm the plant.

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Before you start

Let's start by looking at how we can minimise the pruning we need to do.

You see, pruning cannot be used as a substitute for bad plant selection. For example, if the plant chosen for a particular area is too high or too wide, pruning will not solve the long term problem. Pruning will not stop the plant from growing, it will only slow it down or change the direction of growth.

Once a plant has been pruned it will always try to grow back to its natural shape, height and spread. In a situation where the plant choice is wrong, it is probably best to replace the plant with something more suitable.

Before you start, you should know about the natural growth habit of the plant you are about to prune. It is important to know when the plant you are about to prune will produce new growth and when it will flower and fruit. Lilly is our resident plant expert, and she has some excellent information on plant growth habits.

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Why is pruning needed?

So, you would like more information about why we need to prune shrubs and small trees.

Pruning shrubs and small trees is carried out for one or more of the following reasons.

• To improve the health and appearance of the plant

• To control the plant's height and spread

• To shape the plant

• To influence the quantity and quality of flowers and fruit

• To control the root system of the plant

• To balance the foliage and root system of the plant.

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When should I use organic soil amendments?

You should use organic soil amendments when you want to improve soil. Organic soil amendments include:

• well-rotted manure

• compost

• peat moss

• leaf mould.

By adding any of the above, or a combination of these, you will help clay soils improve drainageand increase the pore spaces in the soil.

Organic soil amendments will also help sandy soils retain moisture that would otherwise be quickly leached away.

Organic amendments also add nutrients to the soil and encourage earthworms.

There are some horticulturalists, however, who prefer not to use these type of amendments in the planting hole. They believe that because they only enrich the immediate area around the new plant, the roots prefer to grow there and are not encouraged to move out into the soil. This may cause a similar effect to root-binding in a container.

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When should I use fertilisers?

Slow-release fertilisers can provide nutrients for a new plant over its first few months in a new site. This means that the plant has enough nutrients to ensure steady growth.

Slow release fertilizers can come in the form of large tablets or in the form of small prills (such as Osmocote® or Nutricote®). There are also organic fertilizers such as well-rotted manure, blood and bone and seaweed-based liquid fertilizers. Your employer may prefer you to use these.

You need to be careful of one thing, though. Not all fertilisers suit all types of plants. Make sure you use the correct fertiliser and the correct amount of fertiliser for the plant you are planting. Using the wrong fertiliser can poison a plant and even kill it!

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What should I do with root-bound plants?

Sometimes, a plant that is grown in a pot or bag can have its roots grow into the shape and size of the container. This means that if the plant is left in the container for too long, its roots will curl around the inside of the container, and the plant becomes root-bound or pot-bound.

Once the roots have grown into a curled and twisted shape inside the container, they are not able to straighten out when they are planted in the ground. This can cause problems for the plant as it grows:

• A root-bound plant won't be properly anchored into the soil and can blow over in strong winds.

• The curled roots might grow around the main root that connects the roots to the stem. Over time, these curled roots can make it difficult for the plant to take up water and nutrients from the soil. This causes the plant to slowly die, and no amount of extra water and fertiliser can help.

There are a few things you can do to help a root-bound plant before planting it in soil.

Inspect the plants when you remove them from the pot. Have a look at the root systems. If the roots are not too tightly curled, then you may be able to tease them out with your fingers.
Make three or four vertical slashes into the root system with a strong knife. Then make one or two slashes into the base of the root ball. This will wound the roots, but will encourage new roots to grow out into the soil.
Some horticulturalists prefer to cut off the bottom two or three centimetres from the root system. If you do this, make sure you use a sharp spade, secateurs or a large, sharp knife. This will wound the root system and give the plant the opportunity to grow new roots into the soil when it's planted.

Remember that some plants don't like their roots being interfered with. Some Australian native plants are like this and can die if you tease out or prune their roots. Always check with your supervisor or a plant expert if you're not sure if the plants you're working with can tolerate this treatment.

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How should I use mulch?

The mulch that is placed around the base of newly planted shrubs and trees is organic. This means that it is made of plant material, such as shredded pruning, woodchips or composted bark.

It's important to use mulch because mulch:

• prevents the soil from drying out quickly

• keeps the roots at a more even temperature and prevents them from being damaged by extremes of heat and cold

• limits the growth of weeds around the plant

• provides the plant with some nutrients as it breaks down (how much nutrients will depend on how much mulch is used)

• gives the newly planted area a neatly finished appearance.

There are a few points to remember when placing mulch around the base of a newly planted shrub or tree:

• Mulch will give the most benefit if it is put about 6 - 10 cm thick. If it's placed too thinly, it won't provide the benefits outlined above. If it's placed too thickly, then it might prevent water from moving through it to the soil below.

• Don't use lawn clippings as mulch. Lawn clippings pack down and won't let water through. They also contain weed seeds and grass runners that can start to grow around the new plant.

• Don't mulch right up to the stem. If you mulch up to the stem, you can cause fungal problems such as collar rot which rots the stem and eventually kills the plant. Always leave a few centimetres of space clear around the stem.

The distance you should mulch from the plant will depend on:

• the size of the plant

• whether you are planting out a whole garden bed or an individual plant

Always check with your employer or supervisor about how far you should extend the mulch before you start.

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What is a weed?

Hi, so you're not too sure what a weed is, eh? Well, let's start by defining what a weed is: "a weed can be defined as any plant growing where it is not wanted".

In the past there were plants brought to Australia from other parts of the world, such as England, to be used as garden plants. However, some of these plants established themselves so well that they became a nuisance and are now considered weeds or unwanted plants. A number of these plants have spread so rapidly that they have invaded other gardens and natural bushland, causing changes in the native ecosystem.

There are two types of weeds that you should know about, namely, annual weeds and perennial weeds.

The ability to identify plants that are weeds and those that are not, is an ongoing process that will take time and effort to master. The important thing to remember is not to remove any plant from a garden area until you know whether it is a weed or not. If you are not sure, you should ask advice from your supervisor or look up a reference book on weeds.

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Maintaining weed free garden areas

Hi, so you need to know why it's important to keep garden areas well maintained and weed free.

Well, firstly everybody loves to see a garden or lawn area that not only looks attractive but also is well maintained. In fact, these garden areas are a credit to those who are responsible for caring for them because weeds may grow:

in plant pots in areas around the pots under benches beside hardstands in pathways in garden beds in lawns

The key to looking after any planted area is making sure you pay regular attention to reducing the weed population and thereby decreasing its potential to produce seed. There is an old proverb that is well worth remembering: "one year's seeding is seven years' weeding". Even if all the weeds are removed there is still the risk of weeds remaining in the soil or being blown to your garden area from other areas. Sometimes seeds are also brought in on shoes and clothing. Any spreading can cause changes in the plant distribution in your own garden as well as to the native ecosystem.

It's a good idea to keep the following points in mind when you don't feel like weeding. Remember, weeds will:

• make your garden look unsightly by spoiling its general appearance

• compete for water, nutrients and sunlight with the plants you do want in your garden

• provide food and protection for many pests and diseases that destroy or damage your wanted plants

• if unchecked, can become a possible fire hazard

• sometimes cause allergic reactions in some people.

I definitely encourage you to have frequent "weed buster days" to keep your plants healthy and looking great!

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Methods for removing and controlling weeds

It's now time to find out how to remove and control every gardener's enemy - the weed.

There are a number of methods for removing and controlling weeds from your garden areas and lawns and each has its place. You need to decide the most appropriate for both the type of weed and its location.

Hand removal Hand weeding should be used when the weeds are growing close to garden plants, particularly newly planted annuals. This method of weeding will minimise disturbance of the root system.

Before weeding After weeding

Hand tools Hand tools such as hoes or cultivators for weeding should only be used where removal will not damage the root systems of wanted plants or where the area is too large for hand weeding.

Weeding with a hoe Weeding with a cultivator

Mechanical cultivation This method of control involves the use of machines such as rotary hoes or tillers to turn the soil over and bury the weeds. It is very good for large areas and quite effective for controlling most annual weeds. However, its success against perennials is limited. To achieve maximum benefit, mechanical cultivation should occur before the weeds set seed. Rotary mowers, flail mowers, slasher and line trimmers are used to control weeds on road verges, vacant land and other large grassed areas.

Slasher used to control weeds Line trimmer used to control weeds

Mowing Controlling weeds by mowing has limited application and is not particularly efficient.

Mower used to control weeds

Note of caution Mechanical tools (mowers, slashers, line trimmers, rotary hoes and tillers) have the potential to cause injury and should be used with extreme care. You should only use them if you have had instructions on how to use them safely, including what protective equipment should be worn when using them.

Mulching The use of organic mulches such as wood chips and mushroom compost or non-organic mulches such as black plastic, pea gravel or crushed stone and bricks are used to control and suppress weed germination. However, there is a risk of fire with some organic mulches.

Organic mulches used to control and suppress weeds Non-organic mulches used to control and suppress weeds

Chemicals The use of chemicals (herbicides) to control weeds should be considered only as a last resort and applied by trained and licensed operators.

Note of caution There is a range of chemicals on the market and, if you decide to use one, make sure you read the labels and instructions carefully to find out the particular weed it is designed for and how to use the product safely. It is important to remember that herbicides are poisonous and you need to know the first aid directions to take if anything goes wrong.

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Selecting the right tool for the right weeding task

One of the keys to successfully carry out any task is making sure you select the right tool for the right task.

When you purchase tools for weeding it is probably best to limit your selection to the type of tool that is most suited to the weeding activity you are likely to be doing in your day-to-day work environment.

I would suggest that you purchase quality tools rather than a cheap version because quality tools will give you long, trouble-free service.

Now let's look at the tools you will require for both light and heavy weeding tasks.

Please note:
The examples listed are tools commonly used in the horticultural industry. However, other tools are available and you may wish to consider them as an alternative.

Light weeding tasks
Tools you will require include hoes, cultivators and small hand tools. You may need a selection of these tools, depending on the weeding task.

Hoes Hoes are used for loosening the soil and scraping away small weeds from garden beds, hardstand areas, and paved areas. Examples: Dutch hoes, swan neck hoes, push pull hoes and torpedo hoes.
Cultivators Cultivators are used for loosening the soil and removing small weeds from general purpose garden beds. The heads used on cultivators may be fitted with rakes and knives. Examples: Three and five-pronged cultivators, and "wonder weeders".
Small hand tools These tools are used to loosen the soil and for weeding between small plants in garden beds. Examples: Daisy grubber, garden trowel, weed fork, weed scratcher and lightweight three-pronged grubbers.
Heavy weeding tasks Tools you will require include a selection of heavy hoes, picks and mattocks and forks.
Heavy hoes Heavy hoes are used for loosening compacted soil and removing large herbaceous or woody weeds from neglected areas to establish new gardens. Examples: Forged chipping hoes, forged burr hoes and forged planters' hoes.
Picks and mattocks Picks and mattocks are used for loosening compacted hard ground, and removing large woody weeds or unwanted vegetation in neglected garden areas. Examples: Double and single-sided miner's picks, road picks, pick end mattock, cutter end mattock and daisy grubber.
Forks Forks are used for loosening and lifting tight soil and for removing large woody or herbaceous weeds from neglected or overgrown gardens. Examples: Forged digging forks and border forks.

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Garden care and personal care go hand in hand

An important aspect of caring for your garden is also making sure that you look after yourself at the same time. This means you always need to think about your personal safety no matter what task you are carrying out.

The thinking and planning phases are essential before actually doing anything in your garden. You need to be fully prepared by selecting the right equipment and work materials for the right task.

Working outdoors means that you need to consider the weather and then dress appropriately. This means in summer you need a wide brimmed hat, sunscreen and sunglasses. A bottle of cool water is an excellent idea and will stop you from dehydrating.

You also need the following protective clothing: a pair of strong leather gloves for your hands, sturdy clothing for your arms and legs, especially for thorny and allergenic plant material, and a good pair of leather boots for your feet.

If your tasks require the use of machinery such as mowers, slashers, line trimmers, rotary hoes and tillers, remember to use them with extreme care. You should only use machinery you have had instruction on how to use safely, including what protective equipment, such as eye protection, should be worn when using them.

Remember to also use extreme care if you are using chemicals (herbicides). Always read the labels and instructions carefully to find out the particular weed it is designed for and how to use the product safely. Herbicides are poisonous and you need to know the first aid steps to take if anything goes wrong.

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Watering requirements for plants

Hi, so you need some help with watering requirement for plants. Well, let's start by looking at why plants need water.

Can you think of a reason why plants need water?

Well, if you said all living organisms, including plants, require water to survive, then you would be spot on! Without sufficient water the plant's quality is severely damaged and may even result in the death of the plant. Both these results have a negative outcome for the nursery because it means that the plant cannot be sold.

You can see why the amount of water needed by individual plants is important. For a plant to grow well, the water lost through evaporation needs to be replaced. The amount of water that needs to be applied can be calculated on the evaporation loss and is usually about 80% of evaporation. You need to keep in mind that the amount of water varies from plant to plant and depends on a number of factors, namely:

• Soil type
  A fine textured soil like clay will require less watering than coarse textured soil like sands or gravels that are free-draining.

• Type of plant and quantity of water
  Plants can be separated into three broad groups, based on their water demand.

Can you think of other factors that may affect a plant's water requirements?

Here are some additional factors that need to be considered:

• plant location

• water quality

• time of year

• weather conditions

So, you can see that even though every plant needs water, the amount needed can vary and depends on a variety of reasons, ranging from the plant's characteristics to prevailing weather conditions. However, here's a guide for calculating your water application rate but there is a note of caution that goes with it. You need to keep in mind all the factors just covered and take the appropriate course of action. If you are ever in doubt, never be afraid to ask your supervisor for assistance:

Happy watering!

• Plant location
  Where a plant is placed in a garden (aspect) will also effect its water requirements. A plant grown in full sun on the north side of a property will have a greater water demand than one planted in the shade on the south side.

• Water quality
  The quality of the water used will determine how the water is applied, for example, the salt content of any water used for irrigation would need to be considered in determining the method of application. This is because water with a high salt content could damage the foliage of sensitive plants.

• Time of year
  Water demand will be higher in summer and lower in winter. However, it is important to remember that the most critical time for water application is autumn.

• Weather conditions
  The water demands of plants will rapidly rise with an increase in temperature and wind velocity, particularly hot, drying winds that lead to a rapid increase in evaporation.

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Watering methods

I'm very glad you've come to see me about the various methods of water application, or in simple terms, watering methods that can be used on planted areas. This is one area of horticulture that looks after both the conservation of our natural resource (some would say precious resource), water, and helps plants thrive by providing the best conditions.

Water is commonly applied by three methods:

1. by hand

2. sprinkler irrigation

3. micro irrigation.

Here's some advice I'd like to pass on about micro irrigation.

Micro irrigation can be installed as either manual or automatic systems and provides better water economy and efficiency distribution than other methods of water application. This method of water application is good where the water to be used is slightly saline in nature.

By hand using a hand held hose, with or without a sprinkler nozzle watering can and buckets.

Sprinkler irrigation fixed, in ground sprinkler systems using poly or PVC piping (manual or automatic) hoses with a fixed sprinkler.

Micro irrigation (poly pipe systems) microjets drippers trickle tube micro sprinklers misters

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The telltale signs of water stress

Would you recognise when a plant is in need of water?

Have a look at these photos and see if you can identify what the problem is.

If you thought all these plants were examples of what can happen to plants when they are deprived of water, you would be right! In fact, these are the telltale signs of water stress, namely:

1. loss of lustre and slight colour change in the leaves

2. curling leaves

3. limp and drooping leaves (known as wilting)

4. loss of leaves (known as defoliation).

So, when should garden plants be watered? This is a question that is commonly asked by those new to horticulture and there are a number of conflicting opinions on this subject. So I will address this in general terms only.

• If a plant shows any signs of water stress, water it immediately.

• Although a deep soak watering in the evening will be of benefit to your plants. It is my opinion that for general maintenance watering, it is probably best to water in the early morning when the evaporation loss is low and the water has time to soak into the soil. This is particularly important when watering plants that are prone to fungal disease so that excess water is evaporated from the leaves with the rising sun.

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Adopting watering zones

Like a lot of other leading nurseries, we've adopted the "watering zones" concept promoted by the Western Australian Water Corporation and have put into practice the following initiatives:

• Labelled all our plants with the drop icons to inform our customers about the plant's water demand.

• Grouped together similar plants with the same watering needs, for example, our Australian native trees are located in one section of the nursery.

• Set seasonal and individual schedules for each planted area, for example, duration times, frequency (intervals - every day, second day, third day, once a week, depending on whether it's summer, winter, spring or autumn).

• Used irrigation sprinklers and devices best suited to the application rate and coverage diameter of the planted area.

The three watering zones are recognised by the following symbols:

1 drop; low water-use plants	2 drop; moderate water-use plants
3 drop; high water-use plants

Have you heard of the following terms: Hydrophytes, Mesophytes, Zerophytes?

There's another term, Sclerophytes for plants suited to low rainfall areas.

Can you identify a relationship between the plant groups and the watering zone concept?

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Tips for watering wisely

Our horticultural enterprise has embraced a number of initiatives, not only in an effort to be "water wise" and conserve water but also to ensure the healthy life of our plants by:

• arranging plants together that have similar water requirements in zones

• irrigating each zone separately from the others

• improving the soil and mulch, and tailoring it to each zone.

My advice to you is to always consider the following points when watering plants:

Here's a rule of thumb that will assist you to determine how much water to apply to your plants:

Watering is essential for the plant's survival but over watering is just plain wasteful and can have disastrous effects, not only on the plants, but also the environment. Be smart and water wisely!

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Giving nature a helping hand

Hi, good to see you again. I understand that you're looking at ways of promoting healthy plant growth and improving plant appearance. Well, you have come to the right place because part of my responsibilities at this horticultural enterprise is making sure that all the plants are provided with the very best growing conditions.

When you were growing up did you ever hear any of the following statements?

• drinking a glass of milk every day helps growing bones

• eating your vegetables helps you grow up big and strong.

I'm sure you've heard at least one of these sayings. Well, technically speaking, plants don't need food like humans because they produce their own sugars from the sun but they do need nutrients to help them to grow strong and stay healthy, and to improve the quality and quantity of their fruit or flower.

Plants obtain carbon, oxygen and hydrogen from the air and water but they also need other elements such as nitrogen and potassium, known as essential elements, and trace elements such as manganese, zinc, iron and copper. These two elements are also known as macro and micro nutrients respectively. In fact, there are 16 essential nutrients needed for plant growth; nine macro and seven micro.

As the names suggests, 'macro' means that the plant requires more of these nutrients, while a lesser amount is needed of the 'micro' nutrients. Regardless of the quantity required, each group of nutrients is extremely important to the plant's growth.

Some regions are better suited to growing particular plants, for example, Australian soils are generally poor in mineral nutrients. This means that unless you are growing Australian natives, the soil will need to be improved in order to grow other species.

Can you think of any other reasons why essential and trace elements need to be put back into the soil?

Well, these macro and micro nutrients are lost from the soil or growing media through:

Do you have any ideas how these nutrients can be put back into the soil?

If you said by adding fertilisers, you would be spot on!

As mentioned earlier, plants technically don't need food but the common term 'plant food' is used when talking about fertilisers because it helps plants to function more effectively. You could say that Mother Nature occasionally needs a helping hand to either replace elements that have been depleted from the soil for various reasons or add elements to improve the soil to help the plants grow better.

I think that's plenty to think about for the moment, don't you? When you are ready, come back again and I'll tell you about the different types of fertilisers and the various methods of applying them.

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Fertilisers

Good to see you back again. This time, it's to find out more about fertilisers, right?

All fertilisers are chemical by nature and can be either organic or inorganic. The difference between the two types of fertilisers is their carbon content. Organic fertilisers contain carbon while inorganic fertilisers have no carbon. Examples of organic fertilisers are manures made from animal excrement and 'blood and bone' made from waste products from abattoirs. Fertilisers can come in powdered, granular or liquid forms.

Have a look at the following different types of fertiliser formulations available on the market and see if you recognise their features and if you can think of an actual product that is used in horticulture:

Always read the package on fertilisers to see what ingredients they contain and to see what planted areas they should be used for. For example 'Blood and Bone' is an organic fertiliser made from animal waste products, is slow releasing, primarily designed for long-term feeding, does not contain potassium and is especially good for building up poor sandy soils.

It's important to remember that fertilisers are:

• expensive to use and should be used wisely, and in the right quantity

• harmful to the environment and need to be used carefully.

granules

An example of this type of fertiliser is: Superphosophate

pelletised

An example of this type of fertiliser is: Agran®

prills

An example of this type of fertiliser is: Osmocote®

pellets

An example of this type of fertiliser is: Dynamic Lifter

liquids

An example of this type of fertiliser is: fish emulsion.

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Applying fertilisers

Hi, I understand you need information on applying fertilisers. Well, let's start by focussing our attention on the different methods available. In fact, there are five common methods used:

• by hand

• non-motorised spreaders

• motorised spreaders

• watering

• injection

Each application method is suited to a particular planted area. You need to choose the right method for the right planted area.

by hand	non-motorised spreaders	motorised spreaders
Suitable for: Small areas, particularly hard to get at places like under foliage, using solid fertilisers such as granules, pellets or powdered varieties.	Suitable for: Small lawned areas, using granulated or powdered fertilisers.	Suitable for: Large area application, for example, school ovals or vegetable and fruit production, using solid fertilisers such as granulated or powdered varieties.

watering		injection
Suitable for: Containerised plants and small garden areas, using watering cans or hose sprayers for soluble fertilisers.		Suitable for: Large nursery, orchard, vegetable or flower production areas, usually integrated into an irrigation system using soluble fertilisers.

Here's some advice on applying fertilisers:

Always check with your supervisor before using any fertiliser to make sure you are using it correctly and that you have understood the manufacturer's instructions carefully regarding how much fertiliser needs to be used and at what application rate. For example 'Blood and Bone', an organic fertiliser, is great for building up poor sandy soils and should be applied at a rate of between 50-100 grams per square metre.

It may sound simple but the consequences of not following instructions exactly when applying fertilisers to planted areas can cause either nutrient toxicity or nutrient deficiency.

It's important to remember that fertilisers are:

• expensive to use and should be used wisely, and in the right quantity

• harmful to the environment and need to be used carefully.

Remember, when using fertilisers, make sure you are wearing the appropriate safety gear! If you are in doubt, ask your supervisor.

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Looking at how plants become damaged

So you need information on treating plants and you're not sure where to start. Well, let's begin by looking at some everyday causes of how plants can become damaged in the first place. Do you have any ideas?

Consider these few ideas on how plants can get knocked over: the wind customers careless use of barrows or carts. So, what happens when plants are no longer upright?

Of course, they can't be watered properly by the automatic irrigation system. This means the media in the pot cannot be wet and will result in the plant either wilting or even dying if it is not noticed. Hand watering may be needed if the plants have dried out.

Plants, like humans beings, can suffer shock from being physically damaged and this may result in the plant dying.

Okay, we have sorted out that problem and the plants are now upright and happy but they can still become damaged. Can you think of other ways?

Well, compare your thoughts with these:

• insects

• snails and slugs

• rabbits, dogs, cats

• fungi

• mould

• bacteria

Can you see a way of grouping these problems together?

In fact, these problems can easily be divided into either causing an injury or disease in a plant. Here's a more comprehensive list, grouping together ways plants are damaged by either an injury or disease:

There are also other important terms that you should be familiar with. They include:

• pest

• pathogen

• malady

• host

Whew, how do our plants ever survive? But wait there's more! Any more ideas on ways plants can be damaged?

How about the following?

• hail

• frost

• humidity

• soil nutrients

• pollution (air and soil)

• horticultural practices such as fertilising, hoeing or over-planting.

Did you recognise any relationship or connection between these various problems?

• living agents

• non-living agents.

Have another look at the above lists and see if you can group them into one of these two categories.

I think I might stop there for the moment. I don't want you suffering from information overload! So, I suggest you spend 10 minutes thinking about the way plants are damaged and the last time you saw one. Then try to work out whether it was caused by a living agent or a non-living agent and if it was an injury or disease.

Wow! If our plants survive all those problems it's got to be a miracle, right?

Of course, there's nothing supernatural about keeping plants healthy, it's just good plant care practices.

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Recognising the signs and symptoms

Just like a good doctor, a horticulturalist needs to able identify the signs and symptoms when examining an ailing plant (our patient in this instance) before the proper remedy can be prescribed.

I think before examining the different signs and symptoms, you really should look at an explanation of what plant pests or diseases are.

Here's one definition for you:

Sounds pretty technical, does it?

Don't worry. It might make more sense when you actually look at some examples of what you could expect to see in damaged plants.

But first it's probably a good idea to look at the meaning of:

• living agents

• non-living agents

• injury

• disease

When you are looking at the various signs and symptoms, take a closer look at how I've grouped them by their cause, that is, by either living or non-living agents. Also notice how I've further divided these agents into a type of problem, for example, whether it's an injury or disease. I did this to help you not only recognise the signs and symptoms, but also to categorise them more easily.

As you can see, pests and diseases leave telltale signs and learning to recognise them is part of the skills of becoming a good practitioner of horticulture.

The next time you are walking around the garden take a little time to stop and examine the plants to see if they are displaying any of the signs and symptoms discussed. Then see if you can make a diagnosis about the cause and problem.

It's important to realise at this stage of your horticultural career that recognising and treating damaged plants is an ongoing learning process. In fact, it involves lots of looking, watching, asking questions and carrying out tasks, all aimed at gaining a better understanding about plants and how to care for them. Like the old saying goes "Rome wasn't built in a day", and it's also true about experience, but the more practice you get. the better you'll become.

Come back when you need to brush up on your skills at recognising the signs and symptoms of damaged plants. Just remember, I am available to see you at anytime - no appointments are necessary and I am always in!

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Living agents

Injury problems The presence of the adult insect

Other signs and symptoms Injury problems include: mottled leaves (yellow or grey) chewed and damaged leaves sting marks on fruit the presence of the insect nymphs the presence of the insect larva the presence of the insect excreta and secretions distorted, wilted and rolled leaves distorted, wilted buds and flowers.

Disease problems Rot on the inside of stem

Other signs and symptoms Disease problems include: wilting and shrivelling and distorted leaves stunted growth spots, streaks, blotches, ring pattern, line patterns or speckles on the leaves furry coating on the leaves reduction in fruit and flower production dwarfing or stunting of growth.

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Non-living agents

Injury problems Yellowing of the leaf veins

Other signs and symptoms Injury problems include: burning of the leaf tips and margins yellowing between the leaf veins dwarfing or stunting of growth.

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Ways of controlling plant damage

Need some more help with controlling plant damage? Great, because there are several common methods used for controlling pests and diseases. They include:

• cultural practices

• sanitation

• biological

• plant quarantine

• physical

• mechanical

• chemical.

Make sure you become familiar with the various methods and ask your supervisor to guide you through each. In fact, you may have already carried out a number of these tasks in your workplace, for example:

• pruning out infected parts

• washing down equipment after use

• removing litter and debris

• fertilising plants

• destroying infected plant material.

As you can see, these tasks appear to be just simple routine horticultural tasks but they actually play an extremely important role in controlling pests and diseases. Carrying out good work practices contributes significantly to maintaining and improving healthy plants. Remember, the old saying, "an ounce of prevention is worth a pound of cure", (penned in the days before we went metric!). In other words, it's easier to prevent a problem by carrying out these tasks, than correct it.

Can you identify the control method each of these routine tasks belongs to?

Never carry out any horticultural task without using the proper protective clothing and safety equipment. It's better to be safe than sorry! Adopting safe work practices ensures that you, your clients and plants are looked after. If in doubt, always ask your supervisor for help.

Cultural practices

Pruning out infected parts

Other examples include: applying good work attitudes adopting crop rotation changing how planting materials are used.

Sanitation

Washing equipment after use

Other examples include: removing dead plants destroying infected plant material removing leaf litter and trash.

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Biological

Lilly Pilly a resistant plant variety

Other examples include: predatory and parasitic insects pheromones genetic plant material.

Plant quarantine

Isolating new plants for a period time in a separate section of the nursery.

Other examples include: quarantining plants (local, interstate or international)

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Physical

Controlling humidity

Other examples include: regulating temperatures (heat or cold) controlling light using gases using abrasive and absorptive dusts minimising physical shock

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Mechanical

Using traps

Other examples include: using barriers swatting (manual control)

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Chemical

Using insecticides

Other examples include: fungicides miteicides