November
Two stroke fuel: Most horticultural two-stroke powered implements are designed to operate at ambient temperatures below 32oC. Operating at summer temperatures, piston scuffing is a likely cause of hard starting. As the warmer weather approaches, increase the volume of oil in your two-stroke mix. This will afford a bit more engine protection. If you use premium two-stroke oil at 40:1, consider using a 35:1 blend (28.5ml of oil per litre of fuel).
Citrus: Citrus trees require comparatively large amounts of nitrogen, so fertilise with a complete mineral fertiliser with additional sulfate of ammonia so the total NPK is 10:4:6. Apply 500g per year of tree age, but do not use more than 2.5kg per tree.
Lawns: African black beetle larvae are active now. African black beetle spends most of its life under the soil surface. They chew stems just below ground level, leaving a frayed edge. Adults become sexually active in spring, and eggs are laid in areas of soft soil. The mating and egg-laying period extends over three months, which is why both larvae and adults can be found in the soil at the same time. Most damage to lawns is caused by the last larval stage, white curl grubs about 25mm long. They pupate in the soil and emerge as adults from mid-January to late-February. These adults feed until the weather gets cold, when they burrow into the soil and become semi-dormant.
Treatment: It is important to treat for black beetle in the Spring when the larvae are near the soil surface, and are easier to kill. Apply insecticide granules or liquid to lawn areas as directed on the label. Water the lawn thoroughly after application. It is important to get the pesticide into the soil where the grubs are.
A recently developed insecticide, imidocloprid (Provado), acts on a different nerve transmission site and provides a new mode of action compared to earlier anti-cholinesterase organophosphates. It is more stable in the soil, which means that timing of the recommended single spray is much less critical. The turf can be sprayed when peak egg laying is reached, indicated by large numbers of dead adults on the surface. Imidocloprid remains effective for a much longer time span, reducing the need for repeat applications. It is less toxic and minimises risk to the person spraying and to non-target birds and animals.
Bad infestations will require three applications of beetle bombs at monthly intervals, to coincide with the life-cycle of freshly hatched eggs.
Bird activity on a lawn provides a really useful indicator that black 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 white curl grub larvae. Eggs are a cream colour just under 3mm diameter and usually laid in pairs. Replace the turf afterwards.
Mowing: Mowing height for buffalo grass should be 30-40mm. Tall fescue should be 50mm
Winter-active grasses such as Kentucky blue, ryegrass and fescue should not be cut low during summer; the plants may be burnt and may not recover. These kinds of grasses should be renovated in autumn.
Dry patches in turf are often caused by water repellence. The grains in sandy loams sometimes become water repellant 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).
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 WA Department of Agriculture has been found to be unnecessary in all but the most stubborn patches.
Fertiliser: Organic fertilisers can be useful when applied at renovation time. More frequent use is unwise. Over-use can increase the amount of disease, may seal the soil surface, increase thatch formation and give soft, easily damaged turf.
Many blood-and-bone formulations are available. They supply N and P in slow-release forms, but no K unless it has been deliberately added. They are useful in seedbeds, but the imbalance between the nutrients means that they should not be used regularly on turf.
Fertilise Tennis Courts with a mixed fertiliser having a N-P-K ratio around 4:1:4 (Munns Greenup, Pivot Special Lawn Manure,Shirley Sportsturf) at a rate of 25kg per court and surrounds. There are three distinct stages in a programme for complete fertilising of lawn tennis courts. High rates of Nitrogen should be used to break the dormancy of the couch in early Spring, followed by a balanced Nitrogen-Potash fertiliser. 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. ALMA Fact sheets FS11 Fertiliser for tennis courts and FS38 Fertilisers for turf have more information.
December
Turf: 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 the couch in late spring or early summer. Water the lawn well after mowing so that the water penetrates at least 10cm deep.
Tall fescues are winter-active grasses that continue to grow into summer if they receive sufficient water and are not cut too low. Recommended mowing height for fescue is at least 50mm through until late autumn.
Winter-active grasses such as Kentucky blue, ryegrass and fescue should not be cut low during summer; the plants may be burnt and may not recover. These kinds of grasses should be renovated in autumn and not in spring.
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Grass webbing mite is active during warm, humid weather. The presence of these pests is not noticed until large bleached circular patches are noticed in the lawn. Dew on the fine cobwebs sparkles in the early morning sunlight. Get down on your hands and knees, and look. Grass webbing mite are very tiny, spider-like creatures smaller than 0.2mm. Various fungi and other pests can also cause similar dry patches. Normally grasswebbing mites leave a fine white web on the blades of grass, but it is only in very heavy infestations that this becomes so obvious that it cannot be missed. The mites are very small but may just be seen with the naked eye. As they are sap suckers the leaves have a silvery white appearance and the affected patch may look quite dry, as though the grass has not been watered. Control with demeton-S-methyl (Metasystox) or with dimethoate (Rogor) at appropriate application rates recommended on the product label. At least one follow-up treatment in 8 days will be required as previously deposited eggs hatch into new mites.
Argentine Stem Weevil: this is a serious pest of cool season grasses and turf type fescues in southern states. Because of their small size and colour they are difficult to detect. Initial symptoms of insect damage include a proneness to wilt due to the damage caused to stems and root systems. The adult weevil is grey-brown in colour and about 3mm long. Larvae are 1mm to 6mm in length and a creamy brown colour with an orange head.
Flooding the turf with a detergent-pyrethrum drench will flush larvae and adults to the surface. A metal cylinder about 15cm diameter driven into the turf to about 50mm depth and filled with the detergent-pyrethrum drench will float any insects present to the surface after about two minutes. Control is obtainred using imidocloprid at the recommended label rate.
Weed Control: Summer active weeds should be zapped with herbicide before they flower and go to seed.
Nasties around the gardens this month include:
Summer grass (Digitaria sanguinalis), a more or less prostrate weed with stout stems and hairy leaves, somewhat similar to Paspalum, is actively growing in many lawns.
Paspalum (Paspalum dilatatum) is loosely tufted with flat, grey-green leaves growing from a stout, woody stem or stolon. Selective herbicide treatment in lawns for both of these weeds is with DSMA applied to actively growing plants. In garden areas apply spot applications of glyphosate.
Lovegrass (Eragrostis curvula). A summer-growing tufted perennial which is widespread in metropolitan areas. Control by spot spraying with glyphosate.
Nut grass (Cyperus rotundus) and Water couch (Paspalum distichium) are difficult-to-eradicate perennials that are becoming more prevalent in home gardens. Spot spray with glyphosate or MSMA from February to April when the plants are growing vigorously. Repeated applications may be necessary.
Milk weed, Petty spurge (Euphorbia peplus) is a prolific seed producer. Try to eradicate this weed before it flowers, which are very small and green. The flowers occur in umbels close to the base of the leaves. Herbicide treatment with glyphosate is effective. Control by applying a pre-emergent herbicide such as chlorthal dimethyl in early spring.
Sow thistle (Sonchus oleraceus) is in flower now, and will continue until autumn. If the plant is sprayed, the fine parachute-like seed will remain viable, ready for next years crop of weeds. Carefully handweed and dispose of the plant, taking care not to disperse the seed.
Barnyard grass (Echinochloa crus galli) is a summer annual with thick stems 50-100cm tall. Leaf sheaths and blades are smooth, and the seed heads are green to purplish, with conspicuous short, stiff bristles.
Johnson grass (Sorghum halpense) is a perennial warm season grass growing up to 1 metre high.
Creeping euphorbia, Pigweed (Portulaca oleracea) and Wire weed (Polygonum aviculare) are mostly found in paving bricks and garden beds. Spot spray with glyphosate
Bindweed (Convolvulus arvensis). A slender, twining herb with arrow-head shaped leaves and pale pink or white flowers. It has a persistent, branching rhizome root system, which makes it difficult to eradicate. It is a noxious weed in many parts of Australia. Herbicide control with 2,4-D or dicamba from bud stage to flowering in January.
There are many opportunities to earn extra income by pointing out to your clients that now is the time to attend to shrub maintenance.
Shrubs: Marguerite daisies and Pelargonium (geraniums) should be trimmed back after flowering. Remove at least one third of the foliage to encourage a dense, bushy habit.
Continue to remove the spent flower heads from roses, otherwise the shrub will expend most of its energy in seed production, rather than producing another crop of flowers.
Hedges of privet (Ligustrum ovalifolium) and Plumbago (Plumbago capensis) are in active growth. 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.
Diosma (Coleonema spp) benefit from a summer trim, but do not remove too much green foliage or all you will be left with is a bunch of sticks.
Ornamental Prunus (flowering cherry, plum) trees can be lopped or pruned hard now to constrain their size. This is more effective than winter pruning, that stimulates fruit production, which then litter the ground when ripe and squishy.
Brown, scabby spots on the fruit of apricots is the result of a fungus disease known as shot hole, which first attacks the blossom, then the leaves, twigs, and fruit if the tree. Preventative measures only can be adopted. At this stage there is no cure. Before the leaves drop in autumn, spray the tree with Bordeaux mixture or copper oxychloride (7.5g per litre of water plus 5ml of clear white oil). Apply the same mixture again after leaf fall and before pruning.
Lawns: It is beneficial to train your lawn in preparation for summer, before the really hot weather arrives. In early December start to soak the lawn weekly, to encourage deeper root growth. If the soil is water repellant, treat it with a wetting agent.
Remember that frequent, light watering will result in shallow roots near the surface that are stressed on hot days. We then feel obliged to give the lawn additional water (waste after waste).
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