I can see some slight discoloration on a few of the leaves but I honestly don't thing it is of any concern unless it rapidly increases. Overall your plants look just fine. Take comfort from the fact that if is was one of the common tomato diseases they would look much worse or even be dead by now and this time of the year problems are 90% of the time just stress and environmental So I'll stick with the points made above - this is "mostly just spring weather effects on plants growing in containers" diagnosis for now. TN weather has been as bad as mine here the past couple of weeks and my plants make yours look like perfection. ;) As the plants adjust to their growing conditions it should disappear assuming no excess feeding or watering. Did you read the info about 'tomato leaf roll'? Can't tell the size of the pots from your photos but they appear awfully small by comparison to the plant itself so I hope they are big enough. Dave

Old topic but wanted to share my input. I'm growing hydroponic tomatoes (various strains) at university in a lab setting (indoors under HID lights) and outdoors in a greenhouse. In one of my greenhouse NFT systems, i recently had a similar problem on 1 tomato plant (total 9 plants that share the same res and tubes). But im gonna try to diagnose your issue by mentioning what others missed out on. 1 major cause of leaf curl is compaction of root system (i.e. roots are compressed or dont have enough space to expand). This risk is exacerbated in hydroponic systems that use tubes. This was the problem i had and had to replace tubes with square tubings that have a liftable top. Once you have access to roots, you must seperate them strand by strand (i.e. so they arent sticking together). In your setup, this risk will further be exacerbated because you filled the entire pvc tube with hydroton (right?). Remove hydroton from tube and place the plant in a net cup with hydroton. Nitrogen burns usually cause browning/yellowing of leaves (similar to sun/heat burn) and not purpling. Test your solution for each chemical if possible, or use a commonly employed aggregated measuring device that shows total concentration in ppm (dont let it exceed 2500). In my system, only one plant was affected. Coincidentally, it was the largest of all plants with the most root mass. I let another normal one grow to its size to see whether it would undergo the same problem, and it did. Viral and bacterial infections that cause leaf roll usually cause it to roll up. Same with the physiological roll. If your leafs roll down AND if your stems bend, this is caused by a diminishing turgor pressure (read: not enough water reaching afflicted area). Mist several times when lights are off (no photosysnthesis) and observe increasing turgor pressure (unbending). Or, untangle roots and remove hydroton from from pipes. I tested various growing methods including fully and partially submerged roots. They all work but a submerged root cannot intake oxygen; it has to borrow oxygen from another part of the plant (i.e. a root part that isnt submerged or above ground stem). This requires energy for transportion and isnt the most efficient (optimal) way for growth and cellular processes. Lastly, an airstone in the reservoir is useless unless the reservoir is completely airtight all the way up to the plant holes. Better to keep small airstones in the pipes right under the plant roots. Those that say aerating the res prevents bacterial development.. is false. If you dont have air in res, you will get anaerobic bacteria (they grow/accumulate slowly but acidify the solution); if you have air in res, you get aerobic bacteria (not acidifying but grow extremely fast). Most bacteria prefer aerobic environments for optimum growth.

All the purpling is normal with young seedling and all the curling leaves are normal too for the most part. Google 'tomato leaf roll'. For future reference, it would be almost 99% impossible for a young plant growing in a cup in potting mix and that has likely spent 90% of it's life indoors to get Curly Top Virus, or any other disease for that matter so relax, ok? :) Dave

Thank you all for your replies. Dave, I keyed in my zip on my first post, but I guess that doesn't tell you much. :-) I live in Ga, and we have had temps in the mid to upper 90s for a couple of weeks now, and the forecast doesn't change over the next week. In the past month, we've had one, yes ONE rain shower, so my poor maters are lacking delicious rain water. I'll check out the article you linked. Thanks! We've had a bit of all that you described...extreme temperatures (from dipping into the mid-40s when the plants were younger to weeks on end of the upper 90s lately), very little rain, and some of the heaviest winds that our area has seen on one or two occasions, so it's impossible to diagnose the root problem I suppose. I water deeply twice per week, always checking the soil before I do to make sure a watering is needed. I've used miracle grow 2 times since planting these guys back in April, plus I tilled compost into my soil back in fall and mulched with compost under my hay...which answers Betsy's question. The hay is actually the same hay I used from last year. I bought 2 bales and only needed one last year. I didn't have these same issues. The older leaves are yellowing a bit, but the plant is producing blooms and tomatoes, so I hope all is going to be ok. Betsy, I kill aphids by hand. I get out there daily (sometimes bi-daily), crawl all around (and underneath) my plants to kill every aphid I can find. :) That's just as easy as squirting them with a hose, which can potentially damage the leaves and wash away pollen. I'd say this year the aphid population has been a moderate, not light, but not exceptionally heavy since I'm pretty darn consistent with my daily killing sprees. lol! There was a period of 3 days when I was out of town where the aphids mulitiplied faster than I imagined they could, but otherwise I'm keeping them at bay. They do seem to be more prevalent on my Big Boy plant (the tangled, curled one) than any of my others, so I guess they've figured out I have a harder time finding them there. Smart critters! Thank you all for your help! Any recommendations at this point? Or should I just be thankful that the plants are still green and producing fruit? :) Thanks! Allyson