Question
Hi Mike,
Hopefully your'e able to assist me, or direct me to where I will find assistance.
I'm very new to gardening, this began as a hobby, but slowly started to turn into a position where I am able to sell off my excess veggies & fruit. I have taken away my back yard lawn and developed a small garden.
Now recently I noticed that some of the leaves of the various plants, like vines & other creeping plants, develop in good condition but then some form pattens as if been too close to heat like a BBQ. and shrivel or die or become jaggered with holes.
My local gardening "experts", all have different opinions, some suggest root rot from over watering, I water daily either early morning before 8am or late afernoons near sunset. Some suggest lack of ground minerals, some suspect "eelworms" getting to the roots. One thought that it might be subjected to a "wind funnel" effect, of mild to strong wind coming through. I've sprayed for various pest.
What is your opinion & advise?
Looking forward to your reply.
Thanks.

Answer
Lin, the advice you've been given is legitimate.  If the soil is composed primarily of clay, it may not be draining quickly enough, which will result in root rot.

Other possibilities include a soilborne disease, pests, or nematodes.  If the problem is a disease or pest, it needs to be identified through either a soil test or by visually monitoring for the exact insect.

My guess is that the soil is infected with a fungal disease.  If a soil test prove this to be the case, you can spray the plants with a systemic product such as a copper-based fungicide.  The problem, however, is that this only slows the spread of the disease, but does not correct the core problem in the soil.

My recommendation is to solarize the soil by covering it with black plastic for 3 months.  This will kill any disease that is present.  Since it is winter, the covering will not have any benefit until the soil warms in late spring.  Therefore, if this is the only area in which you can grow, you will need to cover the entire area immediately.  This will give you a head start next spring and allow you to plant in late spring by cutting slits in the plastic to plant your seedlings.

I would also recommend supplementing your soil with as much organic matter as possible.  These materials would include compost, aged manure, shredded leaves, and peat moss.  Organic soils tend to ward off disease and insects much more effectively.  It also improves the draining and overall tilth of the soil.  Most importantly, organic soil feeds the plants continually throughout the growing season, reducing the need to apply chemical fertilizers.

Finally, make sure you are rotating your plants to a new spot in the garden every year over a 3 year cycle.  Also, grow disease-resistant hybrids to reduce the potential for problems in the future.

I hope this helps.  Please write again if I can ever be of assistance.

Regards,

Mike