Garden Challenges: Strong Winds

Wollongong can be a bit of a windy place, especially at certain times of the year. We're fortunate that we don't tend to be as exposed to the wind as other places due to being on a hill and the backyards on either side of us are higher, giving us a little bit of protection.

However the two days of strong winds last week were certainly exceptional. First was the red dust storm on 23/9 and then the buffetting winds on 26-27/9.

We only suffered one main garden casualty with the winds, which was the snow peas. They simply couldn't hang on to the vegie patch fence with those strong winds. Most of the upper stalks snapped and fell over. I went down to the patch yesterday and trimmed off all the broken stalks. One plant had broken right down to the ground. The other four plants appear to still have some new shoots forming lower down below all the breakage, so I'm hopeful we may still get a bit more life out of them.

Surprisingly, the broccoli seedlings survived, despite no real protection. The young fruit trees also seem to have survived, though the leaves on one of the apples have all wilted and shrivelled, but I think it was doing that before the dust and wind. Hopefully it will come good. And the apple that I had suspected was dead as it showed no sign of life while the other four were growing leaves and flowers, it has a tiny bit of green showing in the top bud.

Powdery mildew

I recently discovered that one of the snow peas was not looking very well. It's leaves had become yellow and mottled. Not knowing what it was, but guessing it was some kind of disease, I pulled the plant out hoping that it would save the other 5 snow peas from the same fate. A week later I could see that the neighbouring plants have developed odd white-ish spots on their leaves, with some of the lower leaves starting to yellow.

From reading some of our gardening books, I took a guess that this could be a fungal problem. A bit of googling later and I believe we have powdery mildew, which can affect plants like snow peas and is probably the result of my late afternoon watering, a few humid evenings and the way the lower parts of the snow peas are dense in foliage which restricts air movement.

I had a look for some organic options to deal with powdery mildew and found a few home remedies. The main one is a milk spray, which is 1 part full-cream milk to 10 parts water. Unfortunately, I didn't have any milk, so I decided to try another recipe, which used 7 teaspoons of bicarb soda, in a bucket of water with enough soap to make a lather. I mixed this up and put it in a little spray bottle.


The other advice on powdery mildew was to remove the worst affected parts of the plants. I removed most of the lower sections of the snow peas. This will also help air circulation around the plants. The lower halves looked a little naked, but I hope it will help. The rest of the foliage was sprayed with the bicarb & soap spray. I did this in the afternoon once the patch was in shade. I've also made a note to be careful watering in the afternoon. While I water at ground level, the spray tends to wet the bottom 10cm of the plant.


The other thing I did notice on the snow peas, which clued me in to the fact that it might be a fungal problem, was the presence of a number of yellow and black ladybirds. I remember from doing my first year biology bug project that these ladybirds feed on fungus. A quick look on the CSIRO entomology website and I found these little ladybirds are Illeis galbula and feed almost exclusively on powdery mildew. Definitely good bugs to have in your garden.

A few days later and the spray seems to have stopped the powdery mildew from worsening or spreading further. I think I'll leave the plants for a bit to see how they go and let the ladybirds feast on the remains.