Yep, it’s that time of year, higher than normal rainfall, higher than normal humidity, warm steamy days and not much wind (except when an extreme storm wanders by, taking everything in its path.)

Fungi are the largest number of plant problems and are responsible for a wide range of plant ill health and disease. They damage plants, killing cells or shrinking them whereby causing stress. Most of the diseases that impact our vegetables are caused by fungi. Fungi can live in the soil, on seeds, leaves, nearby plants and weeds. Fungi is very easily spread by water and wind, moving contaminated soil, on animals and in- sects, on humans, machinery, tools and new seedlings.

The fungus enters plants via openings (stomata) and wounds (pruning), insects and other diseases.

Fungus just love love loves this weather. Your roses could be showing their spots – black spots that is, your zucchini leaves may have a grey furry appearance – powdery mildew and some of your fruit tree leaves would have already experienced leaf curl and are hopefully starting to repair.

Many fungus infections can render the plant deceased, or very unwell.

Managing these fungi can be tricky but viewing the pro- duction system as a whole, through Integrated Crop Protection (ICP) and Integrated Pest Management (IPM) it’s a good start. It’s worth looking at all the conditions surrounding the plant including, all pests and the soil health. Also attempting to understand the fungi including when the plants are susceptible and how you can alter and influence the environment around them.

Tips for managing fungal diseases:

  • Find out the lifecycle, survival conditions and perfect environmental conditions of the fungi.
  • Commit to good hygiene, keep your garden clean, remove weeds and potential fungi hosts.
  • Grow resistant and tolerant varieties.
  • Make sure transplants and seeds are clean.
  • Keep an eye on weather conditions particularly temperature, humidity, and sustained leaf wetness.
  • Have a familiarity of potential fungal problems.
  • Be aware of irrigation implications – overhead watering can compound fungi so consider under watering and timing to minimise peak periods of spore release.
  • Think about crop rotation – using crops with no susceptibility to fungus on rotation
  • Soil testing may be beneficial.
  • Watch your veg crops and fruit trees to be able to have early detection to treat before the fungi gets out of control.
  • Remove and destroy sick plants upon first detection of fungi
  • Understand the advantage of planting time, spacing and complementary planting.
  • Apply preventative fungicides when it is deemed appropriate and based on weather conditions.
  • Thoroughly understand fungicide resistance and rotation of chemical groups.

Even with the best intentions and lots of knowledge you can still end up with fungi problems in a year like this. If a plant does die from a fungus-related condition make sure you dispose of the whole plant to reduce further and future fungus spore contamination.

By Lisa Walmsley

Photo: Yass Landcare plant sale 2021