Backyard Aquaponics
A place to discuss aquaponics

My toms were doing great, healthy, thick stems and rapid growth. Then one by one the leaves curled and they started losing color. This has affect 4 out of 6, with the remaining two looking great.

It seems to set in when they flower, but this may just be a coincidence.

Nitrates are in the red, ph is 6.4. I’ve only added a little iron (I’d run out) and a bit of potassium sulphate.

The weather is hot, (low to mid 30’s), very humid even for Thailand. Any suggestions?

Look up physiologic leaf curl and you'll find several potential causes of the leaves rolling up, including hot weather, high nitrogen, low phosphorus, excess moisture...

http://cru.cahe.wsu.edu/CEPublications/ ... PNW616.pdf

There are also a number of viruses that can cause similar symptoms.

I'm guessing it's a combination of heat, variety, and nitrogen to phosphorus ratios. It may cure itself when the temperature drops but don't count on this happening.

Thanks. That sounds right, except the fact sheet say is happens to older leaves first, which is opposite to my experience. I will add some shade cloth and reduce the water. For plants badly affected, would it be better to pull them out?

Is it possible a mod can change the heading? I meant it to be "Tomato problem, advice needed.