April Hints
White curl grubs active in early winter and feeding on lawns have been identified as pasture cockchafers. Populations build up under similar conditions that favour African Black Beetle, but larvae (curl grubs) are active from late autumn through to September. It is the timing of their life cycle that differs.
Beetle larvae continue to be active if late autumn weather is warm. Signs of larvae activity are characterised by magpies pecking at the lawn after the grubs, and small tufts or clumps of dead turf lying loose on the lawn. These almost give the appearance that someone has done some hand-weeding. Get down on your hands and knees and gently lift any patched of yellowing or dying turf. If the grass lifts away from the soil then this is certain evidence that larvae are present.
Moss may have commenced to grow on damp shaded areas of lawn. Moss is usually due to three factors.
(1) Poor drainage – either the soil is compacted, poorly constructed, or clay-rich and soggy; and
(2) the soil pH is too high. Most turf grasses require soil pH to be between 5.5 and 6.5, slightly on the acid side of neutral.
(3) the mossy area is heavily shaded.
Iron sulphate gives good control of moss and algae and will lower soil pH. Alternatively, your local ALMA contractor can apply an iron rich fertiliser to combat this problem.
Moss will quickly return unless poor soil drainage and overwatering are remedied. Sow shade tolerant turf grasses such as Poa trivialis and creeping red fescue. Mow the grass a little higher to increase turf density and prevent it from thinning out and becoming susceptible to weed and moss invasion. A common feature of mossy lawns is an accumulation of thatch which chokes the turf grass. This will need to be raked out or scarified. Another reason for mossy lawns is underfeeding.
Weed control:
Winter active weeds are commencing to germinate now. The objective of weed control is to eradicate the weed as soon as possible after it appears, and before it produces flowers and seeds. Weed control should be aimed at eliminating and avoiding conditions that contribute to weed establishment and growth. Control should not rely on one method only, but should involve a combination of methods that will discourage weeds while encouraging desired plants.
Hand weeding and cultivation, although slow and tedious, can efficiently eliminate most small infestations of weeds. Regular mowing will prevent tall growing weeds in lawns from flowering and seeding and gradually deplete food reserves in perennial weeds. Mowing will also encourage spreading and thickening of lawn grasses, preventing germination of annual weed seeds. Unfortunately, mowing may also encourage the growth of prostrate weeds which are below mowing height, eg. common cotula (Cotula australis), dandelion, creeping oxalis (Oxalis corniculata). Some of these flower very close to the ground, therefore hand weeding or herbicide control need to be used in conjunction with mowing.
Wintergrass (Poa annua) is a small winter-growing annual grass forming a tussock up to 10cm tall. It first appears about May, with the onset of colder weather and fewer hours of sunlight, and continues to germinate throughout winter and early spring. Seed heads develop in mid-winter and continue into spring.
Treatment requires chemical methods of control. If Poa annua plants are present they can be killed by applications of propyzamide to selectively kill the wintergrass.
We had a comment recently direct from an ALMA Lawnmowing contractor, about a year-old Santa Ana couch lawn where the owner complained of circular scalping marks left by the mower. He was concerned that all the green was removed each time the lawn was cut and that it was just recovering when it was time to mow again.
This lawn had thatch over 5cm (2″) thick, and it was obvious that the mower was sinking in to the turf in places. We advised him to cut more often than every 3 weeks, preferably every week, and that it was the wrong time of the year to perform any turf renovation. As the grass was about to enter winter dormancy, it would be best to cut at the existing mowing height to maintain a green lawn. Scarifying next spring would remove the thatch and sensible care, not over watering or over-fertilising, would result in a better quality lawn. He did confess that the sprinklers ran every day in summer.
Santa Ana couch makes for a superb lawn cover, but it can be difficult to manage. Weekly mowing is recommended by most turf growers during the growing season. Any longer mowing schedule will result in the above problem becoming worse with time. Watering must also be carefully monitored so not to over water, which produces extra unnecessary growth.
Mushrooms appear mainly during the spring and autumn. Often householders wonder if the mushrooms in their yard are edible. If you have customers that are wondering if a certain mushroom in their yard is edible, make sure you tell them to check with an expert. Here are some “old wives tales” that are FALSE regarding mushrooms:
1. Poisonous mushrooms tarnish a silver spoon. – FALSE
2. If it peels you can eat it. – FALSE
3. All mushrooms growing on wood are edible. – FALSE
4. All white mushrooms are safe. – FALSE
5. Mushrooms that animals eat are safe for humans. – FALSE
Remove runners from strawberry plants as they occur as they reduce fruiting. Cutting the bushes back hard, to within 2 cm of the crown will stimulate an autumn crop. Remove all the old leaves and dispose of the away from the strawberry patch. New growth will emerge quickly to be followed by flowers.
Lemons grow best in warm to hot climates with mild winters – they dislike cold weather. Mature trees will tolerate some frost when fully dormant, but even light frosts in autumn or spring will kill young growth. Lemons need a position where they receive more than half a day of winter sun and are sheltered from strong winds.
Italian Lavender can be cut back by one-third or even one-half in autumn.