Garden Basics
- Care & Maintenance 2

Lawn Care 2

Which Grass?
Unfortunately, few of us get to choose the type of lawn grass we have in our gardens. If you are in the happy situation of preparing a brand new lawn, or doing some lawn renovation, make sure that you get some advice about what lawn grass, or blend of grasses grows best in your area. While running type grasses such as couch, kikuyu and buffalo grass establish quickly and spread rapidly, remember that they may invade garden beds. Bunching type grasses on the other hand will remain in a defined area, though some species are inclined to clumping which can open up spaces that can be invaded by weeds. You need to know whether the grass you choose will stay green all year and how it will perform in semi-shaded areas of your garden. Choosing the best species will make lawn maintenance easier in the long run.

Preparation
The effort that is put into preparing the soil before a lawn is laid or sown will make lawn maintenance easier. Giving your grass a really good start so that it develops a comprehensive root system means the grass will survive harsh conditions better. The soil needs to be well tilled and if you are importing top soil, it should be a good sandy loam and it should be incorporated into the existing soil, not just placed as a layer on top. Only top dress lawns if you wish to fill holes that make the lawn uneven.

Planting
Cool season grasses eg bent, ryegrasses, blue grasses and fescues should be sown in winter as they need chilling to germinate. Warm season grasses eg couch, buffalo and kikuyu are best planted in spring. Summer is not a good time to sow or repair lawns and you would need to be very vigilant with watering to have much hope of success.

Fertiliser
Some grasses need more fertiliser than others. Kentucky bluegrass, bent and many of the hybrid couches need lots of fertiliser. Tall fescue needs much less. If you allow clover to grow amongst your lawn grass you will need much less fertiliser as clover fixes nitrogen from the atmosphere in the soil. There are many good mixed lawn fertilisers on the market. The most important thing to remember is to never apply fertiliser to a dry lawn and to always water it in very well immediately after applying it.

Liming
If your soil is acidic, adding lime will greatly enhance the grass’s ability to take up fertiliser. Liming need only be carried out every couple of years and only if the pH of the soil is low. Similarly if the soil is very alkaline, then using sulphate of ammonia will lower the pH. Most lawns will thrive when the pH is between 6 and 8.

Watering
The amount of water your lawn needs depends on the climate, weather, grass species, and soil structure. In normal conditions, a good deep soaking twice a week during summer is generally adequate. Over-watering is undesirable. It is bad for the grass, environmentally irresponsible and unnecessarily expensive.

Mowing
The way that you mow your lawn will also affect how well it survives hot, dry conditions. Increasing the mower height can improve the root system of the grass and allow it to maintain its density. No more than one third of the leaf blade should be removed at each mowing, so mowing frequency should be determined by the length of the grass, not just because it’s Saturday morning!

Clippings
Leaving the grass clippings to lie rather than removing them with the grass catcher is useful from time to time.

Thatch
If too much thatch builds up, it can damage the grass. Remove it with a metal rake.

Aerating
Aerating the soil by spiking can improve the grass’s access to oxygen and improve water penetration. Use an aerator or a garden fork.

Soil wetters
Soil wetting preparations (eg Eco-Wet, WettaSoil, Saturaid) can also be very valuable in increasing the amount of water that actually reaches the root zone.

Weeds, Pests and Diseases
There are many weeds, pests and diseases that can affect lawn grass. The best defence against them is to keep your lawn well-maintained, well-watered and well-fed. Your lawn will then be in the best position to resist or survive attack.

Weeds have a variety of survival strategies. A common one is to grow and flower in a short space of time to take advantage of any opportunity. The opportunity is frequently disturbed ground or increased light. Many weeds produce huge quantities of seed and many are self-pollinated. Some weeds have deep roots or bulbs which can survive beneath the surface of the soil and send up new shoots when the top of the plant is destroyed.

There are a number of weeds that have a reputation for being very hard to eradicate. In southern Australia, one of the worst is Oxalis pes-caprae, known as Sourgrass or Soursob. Soursob grows from bulbs and if you’ve ever tried to pull the plant up you’ll know how easily the bulbs separate and spread. The best time to try to remove the bulbs is during their exhaustion phase in mid-May. A translocated herbicide i.e. one that enters the plant's circulatory system can be used on this type of plant also. Glyphosate is often used. It is sold under brand names such as Roundup, Zero or Glyphosate 360 and is most effective when applied at flowering time.

Blackberries are a major weed problem in many areas of Australia. Blackberry plants sucker, self-layer and self-seed very readily. The seeds are spread not only by birds but also by animals. Eradicating blackberry is an ongoing task. Digging the plants out is uncomfortable but not impossible, but the seed left in the soil will germinate. The plants can be treated with herbicide e.g. glyphosate. The most effective time to use herbicide is when the plants are in active growth e.g. December/January and it should be followed up with a second application in March or April.

Wandering Jew is a waxy trailing succulent that can easily take over and choke a whole garden. It does not respond very well to herbicide. The best strategy is to remove as much of the weed as possible and then mulch the area deeply. When the plant shoots it will be blanched as it pushes its way up through the mulch. It is then much more susceptible to the herbicide.

Other major weeds include onion weed, nut grass, dandelion, dock, milk thistle, Scotch thistle, plantain, oxalis, and bindii.

I do not advocate the indiscriminate use of herbicides and think they should only be used when all other avenues have been exhausted. The best way to deal with weeds is to prevent their establishment in the first place.

1. Try to avoid disturbing the soil. Weeding by digging generally creates a wonderful seed bed for weeds which promptly colonise the disturbed soil again with great vigour.
2. Keep lawns well fertilised and well watered to avoid gaps opening up that weeds can colonise.
3. Keep soil covered. The best weapon in the fight against weeds in garden beds is mulch.
4. Shade is also an effective deterrent. Closely planted ground-covers block the light that most weeds need to grow.
5. Finally, try to reduce the amount of weed seed entering your garden. It comes in in imported soil, in potted plants (especially the common nursery weeds such as willow herb, pearl wort and flickweed), in manures (especially in cow manure) and on the soles of shoes and the tyres of vehicles. Unfortunately there is not much that can be done to eliminate wind-borne seed. If you see a new weed appear, deal with it immediately. Allow it to flower and set seed and you’ll be dealing with it for years to come - as the proverb says, "One year’s seeding, seven years weeding ".

Herbicide Use

Over-use of herbicides and using unnecessarily strong chemicals in the home garden is certainly not recommended, but there are some jobs in the garden that may be simply too difficult or expensive to achieve by any other means. Sensible and careful use of herbicides can control major weed infestations which may also have a serious environmental impact. The thing to remember is to read all the instructions and to follow all of them to the letter.

Non-selective herbicide
The product that is generally considered to be the safest herbicide to use in the home garden is glyphosate. Glyphosate is the active ingredient in products such as Roundup, Zero, Glyphosate 360, No Grow, Weed Control and Weedmaster Blue and a number of other weed killers. These products are non-selective - so you must be careful not to get the spray on any plants that you don't want killed. It is important to apply the herbicide on a still day, because spray drift can kill non-target plants. Roses are particularly susceptible to herbicide spray drift. If you are targeting weeds that are close to precious garden plants, then it may be better to paint the herbicide on to the foliage of the weeds with a paintbrush, rather than spraying it. The product relies on plants being in active growth to work effectively and is absorbed through the leaves, not through the soil. Glyphosate prevents plants from making any more protein ie food, and results may not be apparent for several weeks. You should choose a mild day when there is no rain predicted. Avoid using glyphosate in the depths of winter or the height of summer.

Selective herbicides
The most commonly used selective herbicides are those containing chemicals such as dicamba, MCPA, mecoprop and bromoxynil. These products include Bindii & Clover Killer, Bin-die, Bindii-B-Gon, Kleen Lawn and many of the Weed and Feed lawn products. These herbicides kill broadleaf weeds such as clover, bindii, dandelion, plantain, capeweed and creeping oxalis without harming most kinds of turf. (Be wary of using such products on broadleaf grasses such as buffalo grass however.) Products containing these kinds of hormonal herbicides must be handled with care and special precautions should be taken to ensure the safety of those applying the product, as well as children and pets.

Residual herbicides
Chemicals such as triclopyr are used in tree-killing products and for blackberry eradication. These chemicals can persist in the soil for 6 months or more. Plants treated with triclopyr should not be removed or burnt for 6 months which limits their use in the home garden.

Stem injection
Unwanted trees are best removed physically, including the stump. (A less desirable, but more affordable, alternative to stump removal is stump grinding.) Some trees will persist in suckering and reshooting. The safest way to use herbicides to kill such trees is via stem injection. Do this while the trees still have their canopies of leaves. Shallow holes are drilled at an angle into the trunk and the concentrated herbicide injected. The holes are then stopped up to create an airlock so that the product is more readily absorbed into the plant's sap system. Think carefully about poisoning trees, as dead trees are much more difficult and expensive to remove than live ones. Obviously killing trees in someone else's property is a criminal act, and conflicts between neighbours over trees need to be resolved in a legal and hopefully co-operative way. Some councils provide mediation services so that such disputes between neighbours can be solved to everyone's satisfaction.

The best position for a lemon tree is in a sunny, but frost-free position, where there is protection from prevailing winds. The soil must be well-drained. If you have heavy clay soil, then planting the tree in a raised bed is a good idea. Make the planting hole very wide and basin shaped.

Lemon trees have shallow, fibrous root systems than can dry out easily in hot or windy weather. Regular watering is essential to keep the tree healthy. Water the area around the drip-line and beyond. If the soil dries out, flowers, leaves and immature fruit may drop.

Lemon trees need fertiliser that is high in nitrogen. You can use a special citrus fertiliser or a mixed fertiliser with a high N component. (Most mixed fertilisers have an NPK of around 5:1:4 so you would look for one with a higher N content.) Blood and Bone is an organic fertiliser high in nitrogen. Thrive is a liquid fertiliser with a high N content and can be used as a "quick fix" if the tree is showing signs of nitrogen deficiency i.e. yellowing mature leaves. However, yellowing may be a sign of other problems. If the young leaves are turning yellow in between the veins that remain like a green skeleton, then the problem is most likely to be iron deficiency and this is often caused by alkaline soil or poor drainage. Apply iron chelates. If the tip and the edges of the old leaves turn yellow, leaving a green triangle at the base, then it may indicate a magnesium deficiency. Treat with Epsom salts. Remember though, that yellowing of leaves may be caused by water stress, cold weather, or other factors, so eliminate these first!

Mulching is important to keep roots moist and to prevent weeds from growing around the tree. Lemon trees dislike competition from grass and other plants. Mulch should not be deeper than 7cm and must be kept well back from the trunk to prevent the development of collar rot.

Pruning

Lemon trees often do not need pruning much at all. Tidy up any wayward branches and cut out dead wood. It is a good idea to prune off lower branches to allow air to circulate freely under the tree as this discourages the development of some fungal diseases.

Gall Wasp: These wasps lay their eggs in the stems of lemon trees. Thickened, lumpy stems indicate the presence of these wasps. The galls must be cut out and destroyed. Burn them if you can, or place them in a well sealed black plastic bag and leave them in the hot sun for several weeks, before placing in the rubbish bin.

Gardenias are acid-loving plants so can be combined well with camellias, azaleas and rhododendrons to add the dimension of perfume to the floral display. They do however, require a warm sheltered position, safe from frost, and could perhaps join the daphne along a east or north-east facing wall or fence, which receives early morning sun, but is lightly shaded later in the day. If the plants are subjected to excessive cold or if there are significant fluctuations in temperature, the buds will often drop without opening. The buds will also drop if the plant is drought stressed. In full sun, buds and flowers can scorch.

Gardenias require deep, well-structured, well-drained soil enriched with plenty of compost. They need to be kept well-watered during dry spells. Planting these shrubs in soil that is too alkaline for them i.e. more than 6, can cause a magnesium deficiency which leads to yellowing of the leaves. Watering the plant with a teaspoonful of Epsom salts dissolved in a bucket of water may fix the problem. However, mulching the plant generously with leaf mould and fertilising with azalea and camellia food will generally keep the plant healthy and flowering.

Gardenias are susceptible to attack from nematodes and this will lead to eventual leaf yellowing and may finally kill the plant. Infested plants will tend to wilt even when well-watered. Nemacur will kill nematodes, but if you prefer an organic option, surround your gardenias with marigolds which interfere with the nematodes' ability to reproduce. Gardenias are also sometimes invaded by scale insects and these can be dealt with by the use of white oil. Weevils can chew holes in the buds and leaves. Aphids, thrips, mealy bugs and hawk moth caterpillars can also be a problem at times.

Gardenias can be pruned lightly after flowering if needed.

TO SUMMARISE

Yellowing of leaves of gardenia is most likely to be caused by:
the normal cycle of the plant which tends to drop some lower leaves, especially in spring.
lack of water
lack of nutrients generally
magnesium deficiency
nematodes

Bud drop is most likely to be caused by:
drought
cold
temperature fluctuations
lack of light
poor drainage

Growing Bulbs

The majority of the bulbs we grow in our gardens are spring flowering bulbs. Actually, this term is used pretty loosely as many of the so-called "spring" flowering bulbs actually come into bloom in winter in milder climates. Weather conditions can also affect when the bulbs flower. However you can generally expect the jonquils and leucojums to flower first, followed by the daffodils, lachenalias and grape hyacinths and then freesias, ixias, sparaxis, anemones (see right), ranunculi, Dutch iris and tulips with species gladioli, lily-of-the-valley, bearded iris and bluebells well into spring.

Preferably select bulbs from specialist bulb growers. There are many that provide mail order catalogues or you can purchase online. The bulbs are planted in autumn. Plant all the others except the tulips in March and April. Tulips will not grow in hot climates but they can be successfully grown in cool and upland areas by giving them an "artificial winter" in the crisper of the fridge. Put the tulip bulbs in labelled paper bags in the crisper of the fridge in late March. Plant them in cool weather in May.

Prepare beds for planting all bulbs by digging over well and adding some bulb food or blood and bone. Almost all bulbs are planted pointy end up (except for ranunculi - plant them with the "claws" facing down). Generally how deep you plant the bulb depends on its size. As a general rule, make planting holes twice as deep as the height of the bulb. Plant them in groups of the one kind of bulb. They can also be very successfully grown in pots - wide bowl-shaped containers are best.

Keep the bulbs watered. In most cases the leaves will appear first and then the flowers. When buds appear, fertilise again with a liquid fertiliser. Snails love daffodil flowers so protect them with snail bait. Aphids can damage emerging tulip buds. Spray into the unfolding bud with pyrethrum spray.

Remove spent flowers once they are done but do not remove the foliage. Care of this foliage determines how well your bulbs will flower next year. Apply more bulb fertiliser or blood and bone and keep the foliage well watered until the leaves yellow and die down. Most bulbs can be left in the ground to flower again next year. (Be careful not to damage them when over-planting with summer flowering plants.) Tulip bulbs need to be lifted as soon as the foliage has died off. Brush off the dirt, trim off the old stalks and roots and store them in a dry airy cool place until the following March. (Putting them in paper bags and then into old pantihose suspended from a hook generally works well. Alternatively, store them in airy baskets.)

There are bulbs you can plant for flowering in summer and autumn also. Look for these in the winter bulb catalogues.

A herbaceous perennial is really any plant that is not woody and whose life span is longer than two seasons. However, the term herbaceous perennial is very often applied specifically to herbaceous plants that are dormant for part of the year. This dormancy is useful because it means that the plants can share garden space with other plants eg winter flowering bulbs that grow and flower while the perennials are in shut-down mode.

Most herbaceous perennials need to be cut right back when flowering is finished. When this pruning occurs depends on when the plants flower. Cinerarias, for example, flower in late winter and early spring. They can be cut to the ground when the flowers are spent, usually in October and will remain dormant over the summer with just a few small leaves close to the soil, so that you know where they are. Japanese windflowers flower in autumn and can be cut right down in May. They can be grown in the same bed as winter and spring-flowering herbaceous perennials.

Many herbaceous perennials can be easily divided when they are dormant. This has the advantage of preventing the clumps from becoming overcrowded as well as creating new plants that can be used elsewhere in the garden.

Herbaceous perennials produce a whole new flush of fresh foliage each year so that they look fresh and regenerated. Pruning them back will enhance this and also promote generous flowering. Fertilise the plants with a slow-release (eg blood & bone) or controlled release (eg Osmocote) fertiliser when you see the next season's new growth start to appear.

Herbaceous perennials include: aquilegias, penstemon, asters, windflowers, cinerarias, polyanthus, rehmannia , campanulas, foxgloves, delphiniums (see top right), achillea, eryngium, perennial phlox, statice, helenium, plectranthus, rudbeckia, perennial salvia, centranthus, chrysanthemum, dicentra, liatris, lythrum and physostegia, but there are many more. There is also a wide range of evergreen perennials as well.

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