Is there a (tomato) doctor in the house?

[txice]

Okay...so I have another question. Mixed among the pepper plants I have in the system I previously posted about in this forum are a couple of tomato plants for the wife (she loves those things!).

Anywho, have noticed lately that the tomato plants look very "droopy". My initial impression would be a lack of water...but I've researched that too much water can do the same thing. As usual, I'm confused and decided to come here to see if any of you more experienced growers have ideas.

Pics included below (sorry if they are too big). Some specifics to go along with the pics. These are currently sitting in my smaller "cloner" aero system I posted about in this forum. The nutrient solution is on the warm side...running around 77F right now. We're looking into getting a portable AC unit to place in the room in hopes that if we can keep the ambient temp down the nutrient solution temp will drop some. Exploring other options for cooling as well. Nutrient pH is pretty stable and hovers right around 6.0 ~ 6.2. TC meter is showing a ppm of around 1100 ~ 1200. I don't have any more sophisticated testing equipment to be able to measure the individual nutrient levels though. I'm using the TechnaFlora "recipie for success" veg cycle recipie. As you can see in the pics, the roots appear alright (at least to me). Heck of a lot longer than they were when we first put them in there. They have a nice whitish color to them (not a pure white, but certainly not brown either). Week before last I was on a constant spray cycle with the pump running for the entire 16 hour light cycle. That seemed to be raising my temp in the nutrient solution up quite a bit so I dropped back to a 15 min spray/45 minute off cycle and have been running on that cycle since last week. Lighting for this system is still the 2 4' dual buld t8 flourescent shop lights with the generic bulbs from local hardware store (not the fancier higher output ones made specific for plants - Will be moving these guys under a 400W MH soon though).

I'm hoping this is just lack of water and that maybe the roots are drying too much during that 45 minute dry cycle. Any other thoughts?

[GpsFrontier]

Anywho, have noticed lately that the tomato plants look very "droopy". My initial impression would be a lack of water...but I've researched that too much water can do the same thing.

I don't know the min on/off times for your timer but that seems a long time to go without water. You might try 15 on 15 off, or 5 on, and 5 to 10 min off. Also the roots are long and look like they might be hanging in the water, you might want to trim them back or tie them up somehow. I would try to get the nutrient temp down. I don't know what the room temp is but most tomatoes like warm weather. I would check the temp at the leaves to make sure the lights are not too hot, but the room temp should be between 80 and 90 degrees with low humidity because they don't like wet foliage. A simple test would be to go back to your old watering cycle and see if it changes anything, you should know in less than 24 hours. If you have the pump continuously running you should know in a couple of hours.

[txice]

The timer I'm using for the pumps currently can only go as low as 15 minute increments. Which I guess is actually pretty good for the type of timer we have because now all I can find in the stores are similar style timers that only go as low as 30 minute increments.

The roots were indeed getting to the point where they would be touching the water.

I moved the tomato plants (along with a few of the pepper plants) into the new system shortly after making my initial post. In this new system I'm using 3.75" net pots filled with hydroton. The roots were wound up a little bit with only a tiny bit poking through the bottom of the net pot....so roots hanging in the water won't be an issue again for a while yet. When I put the plant in the new system, I left the pump running continuously while the family and I went to go see a movie (2nd trip for the girls to see New Moon...they were geeked...but I digress). When we left one of the stems of the tomato plant was just about 1/4" from actually drooping low enough to touch the top of my container lid. When we got back from the movie and I came up to check on the plants, that same stem was propped back up and hanging a good 3 or so inches from the lid. The leaves look a bit happier as well. So with a continued flow of water again it has appeared to have helped, at least in the short term.

Once I can make a couple of timer swap outs, I was debating either leaving them on for the entire light cycle again...or at least going to a 15 on/15 off cycle and see if they do better that way. The hydroton in the net pots seems to hold moisture a tad better than just the roots hanging in mid air too.

Still trying to get the hang of this stuff. At least I'm going on 4 weeks in and haven't just outright killed anything yet...heh. So I guess I'm not totally screwing this up yet .

[GpsFrontier]

I left the pump running continuously while the family and I went to go see a movie (2nd trip for the girls to see New Moon...they were geeked...but I digress). When we left one of the stems of the tomato plant was just about 1/4" from actually drooping low enough to touch the top of my container lid. When we got back from the movie and I came up to check on the plants, that same stem was propped back up and hanging a good 3 or so inches from the lid. The leaves look a bit happier as well. So with a continued flow of water again it has appeared to have helped, at least in the short term.

I'm not surprised, roots that don't have any growing medium to hold moisture will dry out much faster. For the same reason plants grown in an aeroponic system need to be watered much more frequently, like every 5 to 10 min. I was thinking that the roots above the water level were getting dry with 45 min before water. Also the roots below the water level could be to getting waterlogged.

I was debating either leaving them on for the entire light cycle again...or at least going to a 15 on/15 off cycle and see if they do better that way.

With the plants in a growing medium now you should be fine with 15 on/off, you might even be fine with 30 off because the grow rocks will hold moisture so they wont dry out as fast.

Still trying to get the hang of this stuff. At least I'm going on 4 weeks in and haven't just outright killed anything yet...heh. So I guess I'm not totally screwing this up yet

Your doing just fine, with anything new there's always a learning curve. My experience is, the more you learn the more there is you don't know. But doesn't that always seems to be the case? The way I look at it is, the one who doesn't try is the one that fails.

[Luches]

Hi txice,

If your new 45min off cycle would dry out the roots, the plants would bend over and eventually die quickly. But 30 off- or 15/15 is safer anyways and will permit better uptake of nutrients as well. But you most probably have decreased the off-time already I guess.

Your PH is fine but the 1000-1200 ppm for those baby plants seem a bit high to me. But then again it depends on the formula:

Because "veg cycle recipie" sounds like a high nitrogen formula to me and if it comes in relatively high strength, the nitrogen content versus Potassium is likely to be too high. The "droopy" part may indeed be due to too vigorous growth because of high nitrogen content (and a lack of potassium).

From my perspective, tomatoes shouldn't be grown with a "vegetative formula", unless the formula respects the fact that tomatoes shouldn't be overfed with nitrogen at any growing stage. I strongly recommend to switch to a formula that is lower in nitrogen content (and obviously higher in K). In commercial terms, that would probably be a bloom- or flowering formula.
A "real" tomato formula would do the deal as well.

PS: While the concentration of 1000-1200 still MAY be OK for that size of tomatoes, it is too high for the baby peppers - at least for my understanding and experience. And I am growing all kinds of hot and less hot peppers since many years. While peppers can use (and cope with) some more nitrogen, they also need high potassium.

[txice]

Thanks for the reply Luches. I'm actually pretty clueless on the nutrient "stuff" so far. I've been trying to study up and learn what nutrients to use, when, and what to look for in the plants should there be a shortage and/or abundance of a specific nutrient. I have flash backs of having to cram for botony finals back in college :/...hehe.

I came into this basically not knowing a single thing about any of this stuff and have been trying to learn as I go...but I know I have a long way to go. When my friend and I visited a local hydroponic store to get materials for our first build, the guy at the store simply recommended we get the TechnaFlora "starter kit", which we did. I've simply been following the "recipie" that came with the data sheet in the starter kit. You can see the sheet I got by going here: Technaflora Plant Products - Recipe For Success and clicking on the US Imperial and/or English version of the file....and you can see exactly what I'm mixing up if it might help shed some light on anything.

I have decreased the off cycle for the pumps. All the systems are now running on a 15/15 on/off cycle during the light period. I'm experimenting with the cycle times during the dark period, but currently have it on a longer cycle. Not sure if this is wise or if there is a need to keep the feeding/watering quite as high during the dark cycle. Though I saw some improvement once moving the tomato plants to the new system and keeping the pump on continuously, a few of the leaves on the plants still seem very "droopy" and "saggy".

[GpsFrontier]

I'm experimenting with the cycle times during the dark period, but currently have it on a longer cycle. Not sure if this is wise or if there is a need to keep the feeding/watering quite as high during the dark cycle. Though I saw some improvement once moving the tomato plants to the new system and keeping the pump on continuously, a few of the leaves on the plants still seem very "droopy" and "saggy".

Generally plants don't need watering during the dark period (but shouldn't hurt) because they don't feed in the dark. Though if the roots are hanging in mid air they will dry out off and that would probably cause problems. I have not done an areoponic system yet, but I would want the roots to get some watering at night to keep them moist.

[txice]

I had always kept my smaller "cloner" system setup with a 15 minute cycle every 2 hours during the dark period and that seemed to do alright. The first night I moved some of my plants into the larger system, I didn't have a timer on the pumps yet and I simply turned them off for the entire dark period. The next morning when I checked on the plants one of my pepper plants had drooped all the way over and was laying on the lid of the system. About 15 minutes after having the pumps on again the plant was perked back up and standing tall again....so it obviously didn't like not getting any water at all (even though it was in a net cup filled with hydroton and no real root mass extending out of the pot yet). Yesterday I was able to get the pumps back on a timer running the 15/15 cycle during the light period and on a 15 minute cycle every 2 hours durin the dark cycle. Checking on the plants this morning they all seemed alright and (at least somewhat) happy. I think I'll stick with this cycle for a while and see how things go. Luches has got me really curious about the nutrient mix now so I'm going to try to keep researching that and hopefully I can get everyone to be really happy and growing. I do at least see continued development in the plants daily...so that's a little encouraging. Some of the plants (tomato especially) just don't seem to be as healthy as they could be, so I know I'm not "on the money" just yet.

[txice]

So a slow day at work = lots of internet research being done. Luches got me curious on the whole nutrient issue and extended research is certainly indicating that I'm probably running "too rich" so to speak. General consensus seems to be that plants early in the life cycle need lower ppm. Additionally the consensus seems to be that in a recirculating system ppm can be lower too due to the continuous feed of water/nutrient.

I'm thinking what I should do is stick with the Technaflora recipie for success, but simply cut back the overall dosage by X% while keeping the right proportions outlined in the recipie. Figuring out what X should be is the next trick. I've read where alot of people will start out with as little as a 1/4th strength mix and move up from there. That seems awfully low to me though (would reduce to somewhere to around 275ppm following the 1100ppm recipie). Think I should go that low? Or maybe just drop it by half and try out a solution of about 500-600ppm?

[GpsFrontier]

The first night I moved some of my plants into the larger system, I didn't have a timer on the pumps yet and I simply turned them off for the entire dark period. The next morning when I checked on the plants one of my pepper plants had drooped all the way over and was laying on the lid of the system. About 15 minutes after having the pumps on again the plant was perked back up and standing tall again....so it obviously didn't like not getting any water at all (even though it was in a net cup filled with hydroton and no real root mass extending out of the pot yet). Yesterday I was able to get the pumps back on a timer running the 15/15 cycle during the light period and on a 15 minute cycle every 2 hours during the dark cycle. Checking on the plants this morning they all seemed alright and (at least somewhat) happy. I think I'll stick with this cycle for a while and see how things go.

Plants that small tend to respond much faster to there environment. So even though they don't feed during the dark, it's wise to keep an eye on them and if you see wilting to increase the watering frequency. With my pepper plants, they got watered 30 on 30 off all day, and until about 1 hr after dark, then started 30 min before first light. During the night I watered them 3 times at 30 min ea with no wilting at night. This was during summer when the night time temps were around 95-100, and day time temps were got up to 115 at that time. I started with store bought plants though, so they were already about 6-8 inches tall and the relative tempuature was a little cooler. I also had them in upside down 2 litter bottles with a mix of grow rocks and coco chips. Coco chips hold moisture better than grow rocks.

(NOTE: You want the watering to continue into the dark (not twilit), and you want it to start at least 30 min before twilit.)

Right now I have 3 systems running. One gets watered twice during the night for 30 min each with no wilting. The other two are on the same timer and only get watered once at night from 11:30 pm to 1:00 am with no wilting. One of these systems is using 3 inch baskets with coco chips and the other one is 5 gallon buckets, also with coco chips as the growing medium. The temp is getting into the upper 40's at night right now, so heat is not an issue. I can probably cut back the watering for all 3 systems at night, but it's not hurting that I can see. With growing plants there are so many variables, the growing conditions, type of system, all the variables of plants growing environment, that observation is your best indicator.

Some of the plants (tomato especially) just don't seem to be as healthy as they could be, so I know I'm not "on the money" just yet.

I am learning how fickle tomato plants can be myself. Mine seem to have a virus or something that is stunting their growth as well as curling the leaves. Through some back and forth with the guys at General Hydroponics, as well as some extreme close up pictures I took of some insects that were later identified to be "Winged potato or pea Aphid's," we are narrowing it down. There are also other factors that are probably contributing, like nutrient temp, the variety of tomato plant itself, as well as cold weather. But it might be just easier to start over because they are still small enough to do that. Trial and error, process of elimination, and observation is the key to learning.

General consensus seems to be that plants early in the life cycle need lower ppm. Additionally the consensus seems to be that in a recirculating system ppm can be lower too due to the continuous feed of water/nutrient.

Yes, small plants wont need a full strength nutrient solution. Seedlings probably around 25%, 3-6 inches probably around 50%. But again everything is not exact because of all the variables, and trial and error and observation are the keys to learning. If you had two growing chambers you can do some testing and see what gives you the best results.

Think I should go that low? Or maybe just drop it by half and try out a solution of about 500-600ppm?

PPM is simply a measurement of nutrient strength, unfortunately a PPM meter can't tell you what elements are in the nutrients and their individual concentrations, just their total amount. For this reason I haven't even gotten a PPM meter. It will however tell you how fast the plant is taking up the nutrients that it is taking up. If you know the type of plants you are growing use more nitrogen this could be helpful, but as I can see only if you can just add back the nitrogen. With pre manufactured nutrients this is not an option.

Just adding more nutrients to the solution to bring it back up to the the desired PPM wont insure the nutrients are in the proper proportions. This is because plants will take up the nutrients they need and leave the rest. One plant might use up more nitrogen, then by adding more nutrients to the solution you would be adding all the elements to it, so the elements that the plant did not take up would be in a higher concentrations, and not in the proper proportions. Most beginners find it easier to just change the nutrient solution regularly, and then get over that initial learning curve first before trying to tackle nutrient composition.