Tomato Question and Answer
One of our readers left a comment, that I decided to answer in the form of a Q&A blog post. I talked to our tech support, and without knowing very much about his grow, we did our best to put together an answer. I think that the information suggested is of value to many different growers, so, here it is!
Q: I am growing brandywine tomatoes in your coco growers and I’m having serious problems. The plants are stunted and fried. All my other systems are working fine. I can’t find ANY info on these new growers? They look really cool, but so far not impressed. What am I doing wrong?
A: Unfortunately, brandywine and other heirloom varieties of tomatoes do not typically do well in hydroponics. Not to say that you won’t find success, but if your other varieties that are doing well are also heirloom varieties then I am stumped.
You should go with a hybrid variety that has been bred for greenhouse production such as F1 Cobra or Mountain Girl. I would guess that you need to cut down the watering intervals to about fifteen minutes on every hour when the lights are on- and fifteen minutes on every two hours when they are off. You should put an extra airline in the reservoir to keep it oxygenated while the circulation is not taking place.
In addition, the tomatoes probably needs some extra calcium as well in order to ward off blossom end rot. That tends to be the number one culprit of tomatoes biting the dust in hydroponics. Also, a 10 mls Gro, 10 mls Micro and 5 mls Bloom per gallon is a good Flora Series mix for tomatoes. Supplement with 10 mls/gallon of our General Organics, CaMg+.
Posted: December 21st, 2009 under FarmLab, Food.
Comments
Comment from Green
Time December 22, 2009 at 11:52 am
I agree with Red, Heirlooms do very well in hydro. As what Red said they tend to be more sensitive to fert. Correct pruning and feeding will yield a healthy crop, has done so for me in both recirculating and R2W!
Keep it Green!!
Comment from Green
Time December 22, 2009 at 11:55 am
Whats yr thoughts on the leaf curl you are experiencing?
Comment from Tiger Lilly
Time December 22, 2009 at 12:41 pm
Thanks for commenting, Green! You and Red-Icculus are both totally right, heirlooms can definitely thrive in hydro. However, when a grower is having trouble with them, and especially when they are running a new system, it can be good to take a step back to genetics that are bred for hardiness in hydro systems. As for pruning, will you share your successful methods?
Comment from Tiger Lilly
Time December 22, 2009 at 12:47 pm
I think the leaf curl is obv because those plants got the s*** fed out of them! 
A lot of the testing we do here is to see how far different types of plants can be pushed. We want to find out where the limits are, and try to go beyond them in the greenhouse!
Comment from Green
Time December 23, 2009 at 10:25 am
LOL, that makes sense, what EC are you feeding at? Also have a look at the difference between day and night time temps, this has also been known to cause leaf curl in toms.
Agreed, some genetics are better suited to hydro than others, however many of these varieties that perform “better” in hydro than heirlooms have lost the sweetness/flavor and aroma of the traditional tomato.
Pruning practice depends of what you are attempting to achieve with the plant. Personally I like to create a plant that is well balanced between vegetative and generative. I don’t like my plants to be to bushy and lush as it makes them “lazy” and retards fruit and flower production. I will leaf prune up to the lowest truss even if the pruned leaf is green and healthy. I will also prune out excessive vegetative growth in the heart of the plant to allow more air movement (less disease and better spray penetration for pest control). This will also help allow more light to penetrate the trusses and help with fruit maturity. I also limit the number of main stems to 1 or 2. This helps the plant maintain vigor and allows for a longer harvest per plant. Higher vigor also helps with fruit size especially with the beef steak types and also reduces flower drop in extreme weather. With beefsteak varieties I will also fruit prune trusses to create larger fruits.
I don’t grow determinate varieties much but when I do I use a slightly deferent method.
Comment from greenthumb@marketshit.com
Time March 5, 2010 at 2:06 pm
If environment – ducting, temp, bugs, etc. are ok then —
1. Flush with Tap Water(1st time-2nd with 10% nutrient) that has been in same environment with resi.
2. Increase light distance – light is lost at the distance squared and they need a break if in shock.
3.Tomatoes & peppers, I don’t care what kind, love to be ‘dry’. Cut the pump cycle gradually but DO NOT stop the air pump to resiv.
4. If using CO2 DO NOT inject directly into nutrient stream – this creates carbonic acid which wastes the CO2 and screws with plants.
Comment from Meow
Time September 11, 2011 at 9:05 pm
The recommended nutrients largely conflict with the results of this Florida study (http://edis.ifas.ufl.edu/cv216). According to the GH PPM calculator (http://generalhydroponics.com/cgi-bin/genhydro/fcp.pl), the recomendations above would have the K at over 50 ppm, even the max recomendation from the research article (more then double until first cluster). While I see that CaMg+ is a good option for bumping only Ca and Mg without raising other nutes even more I am having a hard time getting a GH combo that works according to the research paper and am wondering if a few other hydro tomatoe growers can chime in on their feeding cycle and feedback on the referenced florida research.
Comment from PennyWize
Time September 12, 2011 at 10:19 am
The portion of the study you are referring to is based on commercial pre-mixed fertilizers that contain very high levels of K (potassium). Over 30% by volume. None of our recipes even come close to that. I would recommend using equal parts of all three Flora Series components in order to achieve a good tomato recipe. 5mls/gal of all three is a good recipe until the first clusters appear and then 10mls/gal from there on out.
Comment from Red Icculus
Time December 21, 2009 at 6:15 pm
I beg to differ. Heirlooms and brandywines do great in hydro. The only difference is that they tend to be a bit more “wild” than other hybrids. My Cherokee Purples did just fine at 900 ppm MaxiBloom. I had to dial back the humic and fulvic acid because they were really sensitive to Nitrogen, which affected the bloom set. Heirlooms and brandywines can be done, you just have to not push them as hard.