Plants drying from the bottom up. Why?
 

Hi Folks:

I have some sugar snap peas growing hydroponically in autopots in my greenhouse. All was going well - good growth, flowering etc. and then the leaves started turning brown and drying out starting at the bottom of the plant and then moving upward.

I'm not sure if this is nutrient burn, heat stress (the ambient temp has been in the 70's so it's hotter in the greenhouse), a nutrient deficiency or some other cause.

Any help would be appreciated.

I had some peas growing with the same problem, although the brown was more yellow for me. I think I have figured out what the problem was for mine, but I have a few questions before I can say it's the same thing.

1. What is the nutrient temp (day and night)?
2. What is the pH level, and does it change frequently and rapidly?
3. How old are the plants?
4. Are the plants in the same system with other plants in it?
5. How many plants are there?
6. What type of system are they in (flood & drain, drip, NFT etc.)?
7. Do the roots of the plants intertwine with the root systems of other plants, either other type of plants or even the same type of pea plants?
8. Have you noticed the nutrient solution becoming cloudy, or a foam/film floating on top of it.

P.S. Pictures of the plants and system would be helpful if you can.