Keeping ahead of harlequin bugs

EDIT (March 2018): the following advice works, I believe. I observe plague proportions of these bugs destroying fruit in nearby gardens, while my yard has only a few of them wandering around without causing much problem. I mention removing mallow weeds; I’d remove all tall weed patches around the garden, and if you border on a vacant lot, maybe a strip along the side of it as well. Living weeds and tall grass seem to provide vital harbour even when they aren’t also food.

With a brief moment of warm weather on September 2 this year, the harlequin bugs are on the march again.

Many gardeners around Bacchus Marsh have encountered plagues of these sap-sucking critters. They are remarkably adaptable, feeding off hosts as widespread as mallow, pepper tree, citrus, tomatoes and rhubarb. Most insects that are leaf-chewers only feed off one or a few closely related species of plant, because they need to specialise their metabolism to overcome the chemical defenses of the plant. Sap-suckers bypass the leaf with its battery of noxious compounds, and tap straight into the sweet flow of the plant’s sap, which is relatively free of chemical defenses. Continue reading

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Rainfall report

Clouds shuffle across a sullen sky, staring down at a landscape that is waiting in limbo until the autumn rains. The rainwater tank is getting low, plants not heavily watered have shut down growth as they run out of soil moisture to draw on. Rain will come, but when? And how much?

Previously I’ve had a bit of a stab at charting long-term rainfall trends using Bureau of Meteorology historical data for the town, compared to the recent data from Melbourne Water’s nearby weather stations. With a bit more thought and work I think I have improved the analysis. I’ve also included  more data.

The result, in short, is that rainfall has been declining over the 137 years since the records  began. This appears to be caused mainly by a large decline in autumn rainfall.

I also looked more carefully at whether the south end of town gets less rainfall than the north (as I had previously assumed). It appears that is true and likely to hold with current weather patterns. Continue reading

Burrs: The trials and Tribulus

Tribulus terrestris, three-corner jack

Tribulus terrestris is a terror of a burr. Large, strong spines that can stick into tyres, shoes and of course feet, spreading in harsh dry environments where other plants are struggling, resistant to council spraying efforts.

Locals here usually call it three-corner jack (a reference to the shape of the burrs). Caltrop is another name, taken from a weapon of ancient warfare, a steel spike that was left on the ground to pierce the feet of enemies like a precursor to landmines.

It goes by various common names. One of these, bindi-eye, is more familiar to me as the common name of Soliva sessilis, a small lawn daisy with a nasty burr that my bare feet met as a kid in Queensland.

The weed is well adapted to sandy dry soils and dry weather. It competes for moisture well with other plants, and can survive drought. An annual, it spreads rapidly along the ground in all directions, setting thousands of seeds, which can persist for several years in the soil before germinating. Continue reading

Coffee-table veggie gardeners, beware!

How many backyard gardeners have studied soil science? Who knows the ins and outs of how to best maintain and use a hoe? How many different compost recipes do you know, and how successful have they been for you? Do your plans for bountiful backyard harvests turn into insect-chewed gnarled heads of broccoli, snail-devoured lettuce, and worm-ridden, blight-stricken potatoes and tomatoes? While the pictures on seed packets and nursery seedlings and many popular full-colour gardening books are enticing, actually making it all work is more difficult than many realise at the outset. I suspect many don’t get far beyond the occasional tomato and basil harvest, just big enough to impress this week’s dinner guest, then the crop is virtually finished, the plants exhausted or bolting to seed. Many of us barely manage a couple of tomatoes in pots, oSteve Solomon Growing Vegetables South of Australiar a small bed in the little corner of the lawn or ornamental garden.

Lots of people would nevertheless like to grow a big vegetable garden to get more nutritious, healthy, tasty, fresh food. Perhaps to simply claim a little bit of their personal labour, space and time back from capitalism. It may be a bit “hipster” and inner-city as a trend, but it’s a cheering trend to me. Given that the last serious gardeners in many of our families may have been over 2 generations and 50 years ago (although not in my case), there is a lack of serious knowledge passed down and Steve Solomon’s book, although it focuses on Tasmanian conditions, is good reading for anyone on the island to the north of him too.
Continue reading

DIY Native lawn redux

I posted in 2015 about how to establish a lawn with native grass seeds. But my results were fairly early. Here I report on how it’s going (well!) and re-summarise my (updated) DIY advice.

In a dry but otherwise mostly mild summer, the lawn browned off (that is, leaves died and it turned a straw-brown colour) until we got a good rainfall in early February. Then the summer-growing grasses (redleg grass* and windmill grass*) immediately put on lots of new, green growth. The winter-growing grasses (weeping grass* and wallaby grass*) put up a little new growth, and new seedheads, too. Continue reading

Manna from Mallee

Lerp on Eucalyptus behriana

It’s been a while between posts and there has been a number of things I have meant to write on. Maybe I’ll catch up soon. But on the weekend I went for a walk in the “Melton Mallee” – Long Forest nature conservation reserve, that is – and I’ll share a few interesting things I saw.

I was there on a hot day, which I find is a great time to be out in the bush. The light is strong and really brings out the bright greens and bronzes of Eucalypt leaves and trunks. The sparse shade is all the more welcome, and the big sky stretches above. Not too many animals are out in the heat of the day, and it’s quiet enough to hear those that are. Continue reading