Watering: Remember that a good soaking of water every few days is more useful than frequent light sprinkling. Avoid watering the foliage late in the day; leaves remain wet for hours during the night, increasing the possibility of germination of fungal spores.
Dry patches in turf are often caused by water repellence. The grains in sandy loams sometimes become water repellent by being coated with organic residues from some plant materials. Decomposition of the thatch produced by turf growth can produce hydrophobic materials that accumulate in the thatch and upper part of the root zone.
Testing for water repellence may be simply assessed by placing a drop of water on the dry soil and observing how long it takes for the drop to disappear. Times under 8 seconds indicate no water repellence. Times over 4 minutes indicate severe repellence.
The best way of overcoming water repellence and dry patch is by the use of agricultural wetting agents. It has been found that three light applications, spread through the dry season, give better results than one large application early in the season.
Apply the wetting agent towards the end of the winter wet-season (in September) in most of southern Australia.
Repeat applications should be made in November and March.
After each application, irrigate at a low rate, about 5-10mm per hour, so that the water can penetrate deeply into the affected area.
Shallow coring recommended in the 1980’s by the Western Australia Department of Agriculture has been found to be unnecessary in all but the most stubborn patches.
Lawns: Black beetle were a significant problem last year (1998). Bird activity on a lawn provides a really useful indicator that beetle may be present. Magpies plunge their beak deeply into the soil to reach the beetle larvae. Blackbirds and starlings use their feet to scratch away the turf, which pulls away readily, and find the grubs.
It is suggested that at each call you commence a regular inspection for African Black Beetle larvae. Look for patches in the lawn where birds have been scratching, or where the grass looks weak. Dig a few patches of lawn with a turf plugger, trowel or spade and gently crumble the soil looking for curl grub larvae. Eggs are a cream colour just under 3mm diameter and usually layed in pairs. Young larvae are tiny, about 5mm long and 1mm diameter with a tan coloured head and 3 pairs of legs. Body colour is a darker grey than the creamy-white third instar grub. Replace the turf afterwards.
Any insecticide treatment is much more effective on the first instar larvae than on later stages.
Various fungal diseases will become evident as the days become warmer and humidity is high. Powdery mildew is a common fungal disease which attacks many plant species. It appears as though a white powder has been sprinkled on the leaves and spreads rapidly if left untreated. Treatment is often improved by using a different fungicide. Copper oxychloride, Mancozeb Plus, wettable sulphur, or Triforene are effective.
Set mowing height to 25-30mm as kikuyu emerges from winter dormancy.
Santa Ana, Casablanca, Greenleas Park, Wintergreen couch hybrids all thatch easily. Overwatering and excess fertiliser speed up this problem. Overcome thatch by one very low mowing of couch in spring or early summer.
Raise the mowing height to 50mm for tall fescue lawns (Arid, Droughtbreaker, etc). Tall fescue turf grasses may be showing signs of water stress if the weather has been warm. Tall fescues are winter-active grasses that will continue to grow through summer if they have adequate moisture. Lack of water at this time of the year will set the grass back so that it will not be able to withstand the heat of summer.
Handreck (CSIRO, 1994) states that tall fescue requires half as much water again as does couch to maintain an acceptable appearance.
Weed control: September to November is the best time to treat lawns with selective herbicides, when the leaves are young and growing fast, and the weeds have not yet flowered. Selective herbicides contain plant growth depressants which are taken up by the leaves, not the roots. They upset the growth pattern, causing the plant to die.
Apply pre-emergent herbicides (Dacthal, Kerb, Simazine) for control of selected summer weeds. Refer to fact sheets FS25 Common turf weeds, FS16 Lawn mixture B, FS35 Crabgrass control, FS39 Couch grasses, FS47 The control of weeds in couchgrass.
Blue flowered forest lobelia (Lobelia trigonocaulis) has become a pest of gardens because it seeds so prolifically.
Now is the time to consider applying Monsanto Dimension for the pre-emergent weed control of Crab (Summer) grass
This month is a good time to oversow bare patches in lawns.
Top dress with a mixture of organic compost and sandy loam or topsoil, and add an appropriate lawn seed according to the position - sun or shade.
If obtainable, use seed that has been husked because it germinates faster.
The young seed needs to be kept moist all the time, a sprinkle with the hose before your customer goes off to work is not sufficient.
Rig a length of 12mm irrigation polytube to a convenient tap, to which has been fitted 2 pressure reducing valves (Wingfield part no PR12) and at around 3 metre spacing, plug in riser tubes about 500mm long fitted with greenhouse mistspray microjets (these have a yellow base). These can run all day without using much water and keep the soil just damp, allowing the seed to germinate.
After a couple of weeks reclaim the plumbing ready for the next job. I usually charge the customer a nominal $3 for use of the temporary irrigation, and a $20 deposit.
Fertilise Tennis Courts with 5g/m2 nitrogen to break winter dormancy of couch grass.
The quantity of fertiliser required for a 500 m2 court will depend on the NPK strength of the selected fertiliser.
There are three distinct stages in a program for complete fertilising of lawn tennis courts. High rates of Nitrogen (5g/m2) should be used to break the dormancy of the couch in early Spring, followed by a balanced Nitrogen-Potash fertiliser (2g/m2 N and 1.3g/m2 K) during the active growing period. Before couch growth ceases, a fertiliser high in Potash should be used to encourage plant food storage in the roots to promote vigorous early growth in the following Spring. Refer to fact sheets FS11 Fertiliser for tennis courts and FS38 Fertilisers for turf for more detailed information.
Mulching is useful to conserve soil moisture and reduce weed growth, but do not continue the mulch right up to the plant stems, as this encourages collar rot.
Pop-up sprinklers: This is a good time to service lawn irrigation sprinklers, so that they are ready for the warmer weather. Grass roots grow into the pop-up canister around the piston gland seal, preventing the piston from “popping up”. Unscrew the cap and remove root growth, and wash the filter screen in the base of the piston. Check that the nozzle holes are not obstructed by grit or ants. Reset irrigation controller run times to 8-10 minutes once a week. Later, as the weather warms up, increase frequency to every 3 days, then every 2 days.
Pests and diseases: As the temperature rises aphids become active, feeding on new plant growth. The most effective control is weed control - aphids breed on many species of thistle and other preferred weeds, then transfer to the young shoots of ornamentals. If spraying of ornamentals is considered necessary, a systemic insecticide that enters the plant sap stream is most suitable. Use dimethoate (1 ml / litre water) and remember to eradicate the weeds.
Stone fruit: Leaf curl is a fungal disease that causes leaves to curl up and turn pink. It affects all stone fruit but is more prevalent on peaches and nectarines. Timing is critical; spray just before early bud swell, when the buds are beginning to get plumper. Do not apply after the buds have burst, as it is too late to control leaf curl disease. You will have to wait until next year. Use copper oxychloride (7.5 g / litre water) in August, as the copper will burn the leaves. Chlorothalonil (Bravo, Daconil) may give some late protection.
Hedges of privet (Ligustrum ovalifolium) and Plumbago (Plumbago capensis) are in active growth through to March. Regular trimming every two to four weeks will keep them tidy, and encourage a compact bushy habit. Ivy (Hedera spp) is also growing strongly, and needs to be kept clipped.
Lavender responds well to a hard prune now, to bring it to a more desirable size and shape. Further trimming can be performed in late summer and again in early winter. Lavender seems to flower almost continuously in Adelaide, and it is difficult to decide when to prune. This is why we see great straggly bushes in almost every garden.
Most forms of daisy bush (Marguerite, Euryops, etc) have almost stopped flowering They are best kept lightly pruned to prevent leggy growth. Cut them back now and they will be flowering again during December. Trim them back again as soon as flowering slows down around the end of autumn.
Lawns: Black beetle were a significant problem last year (1997). Bird activity on a lawn provides a really useful indicator that beetle may be present. Magpies plunge their beak deeply into the soil to reach the beetle larvae. Blackbirds and starlings use their feet to scratch away the turf, which pulls away readily, and find the grubs.
It is suggested that at each call you commence a regular inspection for African Black Beetle larvae. Look for patches in the lawn where birds have been scratching, or where the grass looks weak. Dig a few patches of lawn with a turf plugger, trowel or spade and gently crumble the soil looking for mating adult beetles and curl grub larvae. Eggs are a cream colour just under 3mm diameter and usually layed in pairs. Young larvae are tiny, about 5mm long and 1mm diameter with a tan coloured head and 3 pairs of legs. Body colour is a darker grey than the creamy-white third instar grub. Replace the turf afterwards.
Any insecticide treatment is much more effective on the first instar larvae than on later stages.
Aim to spray at egg hatch and remember to water thoroughly with at least 12mm of irrigation so that the insecticide will be where the grubs are, not on the surface.
|Fertiliser||NPK analysis||Quantity required(kg)
|Pivot 4 for lawns||15.5-0.2-7||15
|Complete Mineral Mix||10.5-1.8-5||20
|Dynamic Lifter ||3-2.5-1.6||83
To discourage unwanted clover and some broadleaf weeds in lawns apply Pivot Lawn Mixture B (Cloverkill) at a rate of 100 grams per square metre. Apply when two days of dry warm weather are expected and before the lawn is mown. Allow the lawn to remain dry for 48 hours before liberally watering. Stubborn weeds may need a second spot application one month later. The whole lawn area may go brown after this treatment but turf grasses quickly recover and respond to the fertiliser.
CAUTION: This mixture contains iron compounds which will stain cement and clothing. Stains on cement can be reduced with a paste made from Alum. See fact sheet FS16 Lawn mixture B for more information.
Difficult weeds such as creeping oxalis (Oxalis corniculata) require herbicide treatment to eradicate them from turf. Use MCPA + Dicamba. Bent, Queensland blue couch, common couch, fescue, ryegrass, Kentucky blue, paspalum and winter grass are tolerant to MCPA + Dicamba. Kikuyu and buffalo grass may be injured. Do not mow for 2 days before or after treatment or fertilise within two weeks of spraying. In non-turf areas use Simazine, a selective pre-emergent herbicide to control creeping oxalis.
Mowing: Raise the mowing height to 50mm for tall fescue lawns (Arid, Droughtbreaker, etc). Tall fescue turf grasses may be showing signs of water stress if the weather has been warm. Tall fescues are winter-active grasses that will continue to grow through summer if they have adequate moisture. Lack of water at this time of the year will set the grass back so that it will not be able to withstand the heat of summer. Handreck (CSIRO, 1994) states that tall fescue requires half as much water again as does couch to maintain an acceptable appearance.
Train Your Lawns: Next, train your lawn to become more drought-tolerant. Forget about watering the lawn once a week (or every three or four days on sandy soil) regardless of whether the water is needed. Wait till the top few centimetres of soil is completely dry. This is easy to check with a garden trowel. At this stage, hold back on the water, check the blades of grass each day and wait until about one-third have started to wilt. (At the end of a day, they would have lost their turgid appearance.) That night or early next morning, give the area a good soaking. Repeat this checking performance but each time wait an extra day before watering.
Within a few weeks, the lawn will have developed a deeper, more extensive root system that is capable of absorbing moisture from well below the previous root zone.
By the end of summer, you should have extended the time between watering summer-active grasses, such as couch, buffalo and kikuyu, from once a week to every 10 to 14 days and possibly longer. Even some of the traditional but waterholic lawns, containing fescue, Kentucky bluegrass and ryegrass, can be trained to get by for three or four extra days between watering
The big pay-off comes when it's time to mow the lawn. With less food and water available, the excess growth quickly decreases. At first, there should be fewer clippings to remove and, as summer progresses, it also should be possible to extend the period between mowing. However, it is important not to let the lawn become rank between mowing. If the grass has a pale green appearance and grows poorly after watering, it's time to fertilise.
Any weak spots in the lawn should be obvious after the recent hot weather. Often the problem can be overcome by aerating the soil to enable more effective penetration of irrigation water.