NFT Lettuce
 

Lets talk NFT.

I recently started my bibb lettace in rockwool the same way as described in my dutch bucket squash thread. I have transplanted them into gutters. I went ahead and sprang for the CropKing gutters, all other parts are HomeDepot issue.

From what I have read the cubes should not be touching the bottom of the gutter. I think I may have transplanted a bit early as the roots were not busting out of the cube. I read that if the cubes touch the bottom of the gutter they will stay too wet and I will get root rot. My plan is to reset them in the gutter, keep them off the bottom and wait for the roots to reach out for the gutter bottom. To keep the cubes from drying out I will just hand water them everyday or every other day to keep them moist. Since this is a small system, 1 gutter with 5 in the future, it won't be a problem.

If I leave the next batch in my high tech germinator pan an extra 2 to 3 weeks I would think the roots would be busting out. Again the only problem I see is that the roots still won't be dangling into the gutter flow and I will still have to top water them. I could always build one of the upspraying starter units which will develop the dangling roots I need but this is a pain, I want it to be simple. I'm not sure how commercial growers solve this problem but finding out would answer the question.

I am using the same reservior for my dutch bucket and NFT.

Hi OChydro,

Rockwool isn't exactly the best solution for lettuce in NFT, not for germination and for nursing neither. Actually roots tend to spread laterally in rockwool. I recommend special Lettuce cups, filled with a mix of 1 part Vermiculite and 3 parts of Perlite (both fine grade).

Also, (even if using rockwool) you can't transplant until the roots have grown long enough to reach the bottom of the gully! Just wait until they are at that stage, anything else is pointless (no offense).

PS: use adequate nutrient for lettuce and the very adequate concentration to grow your seedlings, (starting with PH corrected, low ppm, RO or even distilled water for germination and beyond) otherwise you have delayed root growth and loose "vital" time in the ongoing operation.

If you need pics of the lettuce cups, nutrient requirements or other hints, just call in again...

Cheers,
Luches

Thanks for your reply. Pictures of the lettuce cups would be great but I'm not sure how I would use these in my gutters as they have 1 inch square holes, would they fit in my gutters? Please let me know.

Here is the cup with the size. Up to you if you use them and make them fit. As these are bigger than 1' it shouldn't be a problem.
Best is to have the cups in a shallow nursery with a continuous flow of water respectively week nutrient solution (like we have).

http://chiangmai-thailand.com/images/a/cup.jpg

Here they are in action in the gullies.

http://chiangmai-thailand.com/images/a/3sizes.jpg

Well ya, with a NFT system the roots should dangle in the flowing stream of nutrient solution. The dangling roots then wick up the nutrients to get the moisture they need. They also wick up the moisture into the growing medium, keeping it moist. But if the growing medium is touching this flow of solution it will become saturated depriving the root system of oxygen and or air. Some plants don't like keeping their feet wet as much as others. From what I understand Lettuces is a cool weather, low light, water loving plant. So they should not mind there feet being wet as much as others might, but you don't want to deprive them of oxygen/air either.

If you have the capability to adjust the water height, you can raise the height until it touches the bottoms of the growing medium and the roots start dangling down. But you would want to use a timer and set it to go on/off in intervals like a flood and drain system so that it's not running 24/7 as it does in the NFT. Then when they dangle down far enough you can convert back to the NFT system.

Well, you could possibility build something. I am thinking of something like using 2 stackable Tupperware containers, so one will fit inside the other but not go all the way down. Then cutting holes to fit your growing medium in one of them. Place the seeds in the growing medium, and the growing medium the holes. Then place the container with the growing medium inside the other one, and pour in just enough water to keep moist. This should hold the growing medium up so the roots can dangle out the bottom, and using the two containers should hold enough moisture so it wont dry out fast. It doesn't need to be Tupperware, but the idea is to have one container fit inside another so that it will hold the one with the growing medium in the air and provide the space underneath for the roots to dangle down. You could probably find something usable for this at the dollar store.

I have not looked into that at this point. Although all commercial operations usually have greenhouses devoted to germinating seeds and complete control of that environment, including air temp, lighting, humidity, nutrient temp and delivery. This way they have a consent supply of plants the right size to replace the ones that were harvested, so there is virtually no down time and maximizing efficacy. To them building an automated spray system would be nothing.

I was looking for something else when I ran across these pictures of lettuce being grown in a system like yours, with the 1 inch cubes. I thought that 1 inch cubes might be kind of a small hole for the neck of the plant, though I would guess it would depend on the type you are growing. There are hundreds of variety's of lettuce.

Between the cup and the plug a morsel may drop ;)

Does any one know how close you can plant lettuce together in a water culture system? I am thinking of using this system to grow lettuce just because its ez for them and me.

On the picture I've posted it is 25cm, 12.5cm and only 5cm for the tiny seedlings

That would depend on the type you were growing. You don't want them to be crowded, but you don't want to waste space either. How big does the variety you want to grow get? Then space them that far apart, maybe just under that. They wont mind touching there neighbors, as long as they have elbow room.

Commercial type of lettuce doesn't vary that much in size and hence gullies are often pre-drilled to a standard size. You have to settle for some kind of standard size somehow, as you can't change the space next season when changing varieties - or can you? Well, you can always try :)
In case you have a bigger variety, and it's getting narrow, you can always harvest earlier.

Actually I've ordered a new type of gully which has an open top (has removable cover). The cover is made from some Styrofoam and can in fact be changed easily. And, different spaces can hence be used. Also the gullies are much easier to clean with this type of removable top.

In commercial system you ALWAYS have several runs of differently spaced holes for different growing sizes (like shown on my pictures). There is a rotation and the seedlings grown in special nurseries will be moved to smaller spaced runs first, eventually to a larger spaced- or directly to the final, wider spaced gullies.

If running a smaller or medium scaled setup and intending to rotate production, one might even consider having one half spaced run for a pair (2) standard spaced. It is certainly worth a thought!

I have grown them very close together in a DWC and a E&F. I grow mostly looseleaf, and have had good luck.

well my goal is to run a troff system. I am thinking about 32'l x 4'w and about 2' deep unless i need it deeper? I hope not. I have the foam to support them, and i want to grow romaine lettuce as it is my favorite lettuce.

4 inches or feet? Feet wide would should work fine but Romain is kind of a large taller plant and would likely tip over if not supported well. I'm not positive but I think this image is of Romain (it looks like it). In stores they usually just sell the harts of the plant, and take off the large outer leaves. It looks like the foam is 2 to 3 inches thick and supports them well.

The picture is impressive, but this isn't romaine lettuce, not even any other lettuce - no way. Although it's called so at the blog the picture provides from. That looks much more like over matured Pak Choi or some other related chinese kale type. Btw: look at the hand at the left, not at the head of the guy, that gives you a better proportion of the size.

Romaine lettuce can be grown under the very same conditions and setups as other lettuce types. As I said earlier, if some type grows a bit to big - simply harvest earlier. It's more delicious and has higher nutritive value at an earlier stage anyways.

One Foot (1') is standard an deep enough for lettuce in Deep Water Culture.

I have never grown Romain but as I mentioned, I thought it was Romain because it looks like it to me. Is it Romain or not Romain is not the question. The point was that they were taller plants and would be a bit top heavy and would probably fall over in a 4 inch wide trough, if that was what was planed. Even though 4' does mean 4 feet, I wasn't sure if that is what was meant and just wanted to clarify.

Yes, if you look at the hands (what I did) will give you an idea how tall they are. I would guess about a foot. Going by my hands the Styrofoam would be 3 inches thick. The plants are a good 4 to 5 times that, and that would put them at about a foot+ tall. That also makes it about twice the height of most lettuce I have seen growing (like the ones in the images Luches posted). The Romain I get at our grocery store is around a foot tall in height. So whatever it is in the picture, it should be a good compassion.
I have no idea where the image originates from, or what they say the plants are. Also the reason I did not say it was Romain for sure. I have compiled hundreds of similar pictures, and stored them in a file on my computer. I simply do a search for hydroponic plants or what ever I am looking for, using the image search feature from Yahoo, Google and Bing (formally known as MSN). Then save the image to my computer, they don't come with titles or URL's.

It's my understanding that Smurf wants to be able to sell this produce at the local farmers market. Not sure he wants to go to the trouble of building the systems to grow the produce in, only to need to harvest it early because they were too close together. The produce tends to look smaller to the customers that way and they feel like they are not getting their money's worth. You can always cut the price but then you cut your profits. I personally don't see much point in doing that. I would want my customers to feel like there getting a good deal. But at the same time I need to make enough back to cover costs, and also make it worthwhile for all my work.

When sales of hot chocolate go up, street crime drops.:)

Sorry, I have got no time and no patience for any such discussion that always focusses on individual points and hence drifts away from the little objectivity and common-sense that can be expected from such exchange. Unfortunately, there simply isn't a common-sense answer for many questions, but that doesn't mean that one shouldn't at least try to aim for it. And yet, kale is kale and lettuce is lettuce and if there is no point to that difference I don't know where it is.

I've given all needed information so far. If there are more questions, feel free to ask.

Thanks for your help guys ...
Yes i am talking feet not inches thats why i put one ' and not two. I have a great spot for this setup, and wont cost a lot for this system. As i have the foam for it already and the troff wont cost much to build at all. Thanks.

Of course you were talking inches, ehmmm foot - and it was clear and obvious to me. Even though I am not that familiar with US-units, I knew that ' means foot and nothing else ;)
You're welcome.

Except for your own as always. And yet, you always prove you do have the time.
If only you could.
As usual of coarse.

I thought so, but it's so easy to simply hit the wrong key on a keyboard, and it's a big difference. A 4 inch trough would be fine for smaller lettuce plants. Also I thought 2 feet deep was quite deep already, and you mentioned possibility wanting to make it even deeper. So I just wanted to clarify it.

lettuce/root edible plant
 

I was at wally world and they dont have kids pools this time of year. But as soon as i can find a kiddy pool i'm going to float some leafy lettuce type plants and carrats radishes any thing with a edible root.

I'm thinking i will just cut out holes for the plants that will be on styrafoam in net pots. then place a black poly sheet over the whole thing and cut out the holes for the net pots with a x in the plastic so when i shove in the net pot it will tuck the fold of the poly into the foam with it so that the plant cant slide under the palstic or move around. pus it blocks out the light to the roots and water. toss in a really small pond pump i have for circualtiona and a place to fill it and test the solution.

I like the floating idea becuase if you water by hand unless the pool runs out of water the plant is always in the solution at the correct depth. I like the idea of carrot or beat hanging down under the net pot.

I think this would make a great strawberry grow as well with florecent bulbs the lenght of the pool.

about the previuos post/roots dont rot when there wet all the time unless the water is to warm and there is no oxygen? root rot is just that you have created a hydro composter. cool the water add some air stones and those roots no mater how they come into conact with soltuion will be white and thrive.

Years ago i bought a heater core for a chevy pick up. its all aluminum and plastic i put in just after the pump and placed a big computer styel cooling fan on it. I had a dayton air temp control that switched on and off a realy. i bent the thermometer down to touch the water in the resivoier and hooked the fan to its relay switch which i think was points contact like a fish heater.

i could know 5 to 15 degrrees off the solution depending on room tempeture. Now i build chillers out of wall shakers. but where i live just having the nutes on the concrete floor sucks enough heat out of them unless it summer then i have afreezer with some plastic rectangle planters i bought that make a very large ice cube that last all day dropped in a 5 gallon bucket for those really hot august days for a week or two.

Yes, I've seen strawberry's growing in a water culture system and they looked healthy. I have always liked the floating raft water culture systems. Though I have a different system for growing strawberry's that I really want to get running as soon as I have the money.
That's interesting, I know about the temp being to warm (I dealt with that before), and I understand why the need for the air stones in standing water. Although, I also understand that some plants like well drained soil and others are not so finicky. I guess for plants that like well drained soil you would suggest adding extra air stones to get more air to the roots (and extra or larger air pump of coarse)? I would never consider a water culture system for a root crop, but it would be interesting to see how it works out. It would be even more interesting if you could see the crop growing underwater, kind of like hybrid humans/aliens in the large test tubes in the sci fi flicks. I know that light needs to be blocked, but it would be cool if once and a while you could lift the skirt and take a peek.
Sounds similar to an idea that I have for a one room air conditioner. Using just the heater core or small/medium radiator, strapping a fan to it. Then filling an ice chest with ice water and pumping the ice water through the radiator/heater core. I don't think your setup would work for me because the air temp outside reaches 120+ in the summer here, but I would be interested in seeing how you had that system set up in case there are aspects I can use, and it might give me a idea or two.
I tried looking up "wall shakers" but all I seem to get is furniture. I would be interested in seeing how you build these also.

root edibles
 

i always though the root plants would not work for some reason but deep culture works and i have done that for years and my carrots and radishes are very happy in clay pellets. Since i run a drip feed system and it runs over the root it virtually under water?

I bought a great potatoe a week or so ago at the store. its running under solution right now. i am going to float it in a bucket as soon as it has roots.

one time i dropped a seed in nute tank that had a 400 hid over it and it developed roots leaves etc and pulled it out and grew it. i should try this again and see how easy this might be again.

You can small addon heater with a fan already mounted, the fan 12V. I have installed these in equipment before. It's a heater core in a case with a fan on it.

So it's not actually a water culture system, because the roots are in a growing medium and not completely suspended in the nutrient solution? If it's like the systems in the videos, they appear to be a combination system, and not a true water culture system. So the crop part of the root system is actually above the water level, with a drip system on top.

1. the wet feet theory is a common misconception when transferring knowledge from soil to hydroponics. The wetness is anyway not the problem but the oxygenation the wetness prevents. Some plants roots are simply lacking oxygen in too wet soil or media because of there fine roots. The humidity is not the actual reason, but the cause for the lack of oxygen. As soon as there is enough oxygenation, the roots of almost any plants thrive well and stay healthy when completely edit: emerged submerged in water.

2. Temperatures of nutrients have priority before oxygenation. Because the cooler the water the more oxygen can/will be dissolved in water. 24°C is ideal and seen as the best compromise between ambient temperature and dissolved oxygen. If your nutrient solution is too warm, there is no way to oxygenate it further than it can be dissolved in the actual temperature!

3. Carrots (and other root vegetables) grow well in DEEP WATER, but carrots have a tendency to crack and split in deep water culture. Some varieties tend less to split - research has been made to determine suitable varieties that split less and has shown that there are notable differences between varieties.

4. Potatoes definitely grow best in aeroponic systems, where upper parts are sprayed (sprinklers are good enough) and lower roots are immersed in water. In Brazil such technique is commonly used. The setup is similar to concrete pools (covered with styrofaom), but there is about 1 foot of air space between styrofoam and water level. This zone is the actual growing zone which is sprayed permanently or every 15-20 mins.

5. When building a DWC setup from concrete or bricks, building it a bit deeper than 1' can be of an advantage, especially if this part is underground. Half a foot deeper may make the difference of a few degree lower temperatures and prevent you from using "complicated" perhaps delicate and energy consuming, devices.

6. In both DWC and NFT, recycling the nutrients to and through a supplementary underground reservoir is always a good idea. Constant flowing, and dropping from a certain hight may oxygenate the solution good enough. People running such- or other recycling DWC systems, often report very good results.

PS: I am running recycling DWC based nurseries lately (with the lettuce cups filled with a perlite/vermiculite mix as shown before) and I am amazed with the results. :)

A point for clarification to avoid any possible confusion...

I think you mean submerged? You are referring to situation(s) where the roots can thrive when completely under water given enough DO correct? I can't imagine where oxygen would be an issue for roots out of water unless the grow system was somehow air tight or something.

As you may have noticed, I am not a native writer in english language. Yes I meant submerged.
What I wrote is not about what you can hardly imagine, but about wet soil that is more compact and hence does not allow the same amount of root oxygenation. If we talk about wet feet we talk about water that remains for longer in soil and has poor oxygen content, and at the same time prevents soil to "breathe" as it is the case when soil is fluffy, moist but not completely saturated with water. And as we know, some plant's roots deal better with "wet feet" than others - still, the actual problem is not the water, but the lack of oxygenation for some plants' root types under water saturated soil conditions. This issue is actually well known and not something I've invented for the occasion ;)

The other part is that any roots that are (completely) submerged in water, can only uptake oxygen which is dissolved in that water, - oxygen molecules that are present in H2O to be precise. To put it in simple words: the warmer the water, the less molecules can/will be dissolved in that water, no matter how much oxygen (by air pump/stone, mechanical means, etc.) you try to get in.

Point is, that we deal with two completely different environments and cannot transfer insight from one domain to another.

Yes I noticed...and I also fully understand the oxygen concept. Like I said, was just looking for clarification on your word choice so I was clear on the point you were trying to make. Thanks for clarifying.

NFT Lettuce
 

I have 5 plants in my 1 in. gully right now. The weather was been cold and we had over 8 in. of rain at the house. The butter lettuce is hanging on a growing just a bit. I'll try to put some images up but they are pretty pathetic for the time being. I am in So Cal and all of my hydro is outside.

The lettuce I bought from the nursery, rinsed off the soil as best I could is doing well in the aeroponic unit. In the future I will stick with this technique in the late fall and winter. I think the NFT lettuce will excel when the weather warms.

On an interesting note, I harvest my lettuce but don't chop off the head to low, (butter and romaine), and then get a complete second head very quickly since the root structure is already there.

yea, i am going to be out side, but i am waiting for this large storm system to move outa here. also in cali.

deep water
 

thats all very good info.

We were just thinking about a 30 gallon garbage can with the lid flipped upside down and a hole drilled for a potato/tomato plant.

So your saying the potato itself should not be in the nutrient? or it should be and there should be a space of about a foot betwwen where the potatoes grow and the root extending down to them.

I ask becuase i have never grown hydro potato's yet. they are so inexpensive ive always just bought them.

i do have some of those fogger misters i could drop in and go aeroponic?

I really had this idea i would be able to just lift the lid and cut off a potato for dinner with my scissors and the plant would just be happy and continue to grow more.

this is a great topic, hydro potatoes could really help my food production.

in epcot, they grow them. But they have large pots of dirt for the potatoes to grow in. So the plant is in a hydro system, and when they find a tuber bud start it goes in the dirt.

So they have a hydro plant with buckets of dirt around it, and the root with the spud growing stretched over and placed in the dirt?

I to never really considerd growing things like potatoes, carrots or onions (other than green onions) just because they are so inexpensive at the store. Root vegetables seem to keep well as long as they are kept cold and dry, so they seem to travel well and the quality at the store isn't bad.

This is very interesting indeed. I have never grown lettuce as of yet, but always thought you would only get one head per plant. The butter lettuce I get at the store always has the root ball with it. The Romain is cut at the bottom and the base is about 2 to 3 inched where it was cut. Maybe the Romain plant gets much bigger than I figured to be able to make room for more heads.

What it is about is writing what you mean, and taking offense to others if you cant. These are two completely different meanings that mean the exact opposite things. That changes the entire concept of what you were trying to say. Therefore txice was only trying to imagine/picture what you actually said, not what you meant.

e·merge (-mûrj)
intr.v. e·merged, e·merg·ing, e·merg·es
1. To rise from or as if from immersion: Sea mammals must emerge periodically to breathe.
2. To come forth from obscurity: new leaders who may emerge.
3. To become evident: The truth emerged at the inquest.
4. To come into existence. See Synonyms at appear.

sub·merged (sb-mûrjd)
adj.
1. Botany Growing or remaining under water: submerged leaves.
2. Living in poverty or misery.
3. Having been hidden.

lettuce
 

I think the bigger all lettuce grows the thicker and tougher the leaves become. Pickem small for better texture, edibility and esthetics.

I'll take a pic soon

I found the resource (PDF) from Brazil I was referring to, earlier. It's quite informative and complete, with concepts, designs and even a special potato formula! I basically look out for this kind of more scientific studies and projects. I trust them more than dozens of individual opinions based on what is called "selective observations" of some enthusiastic hobbyists. Also, I try to find intel from outside the Box! :)

PS: This is actually about "seed potato" production of specific genotypes and varieties. Hydroponic production of potato isn't exactly lucrative, neither on small, medium or large scale. Simply because they grow so well and easily in soil and have no high market value. Well, unless you combine hydroponic and soil culture, - or in case you have a small amount of a heirloom- or rare potato variety you want to multiply more quickly. Or for some other purpose that doesn't consider rentability in a common way. Rentability is a relative matter, also in this domain.

The Production of Seed Potatoes by Hydroponic Methods in Brazil
______________________________________________

Have you considered changing the nutrient formula according to the climate? If your lettuce grows better and faster in aeroponics (under the same climatic conditions), it indicates that it is related to nutrient uptake. As we know, uptake is accelerated in areroponic systems. Most importantly, a "winter formula" for lettuce looks quite differently, it has notably more nitrogen (and less potassium) and the nutrient strength is somewhat higher. This principle is actually commonly accepted and often practiced by commercial growers. I believe you could easily improve your NFT results by simply modifying your nutrient formula and strength by the book. If you can, of course... Aeroponics for lettuce isn't very economical and compared to culture in NFT gullies, you basically have smaller setups that can only hold a few plants. Why having less production for higher energy cost, if you could improve results by changing nutrient strategy?

I know, for most people, hobbyists and even professional growers, nutrient formulas (their composition, the making or some modification) are still a thorn in their flesh and they prefer going and thinking by product and teaspoon per gallon. But unfortunately this behavior makes nutrient related problems difficult to discuss and to solve.

its just gardening
 

imagine a hydro game show. its on a desert island.

you can have any equipment you want as a group just agree on one type of growing system per group. LOL

all the groups get every food seed they want but one group gets some weed seeds too. I wonder what group won't kill each other and win the game show.

If any group on the planet should get along you would think it would be the gardeners and there cats. My cats name is hydro nip and he admits he has a problem. We start the moring with world peace on the agenda i have my coffe he has some fresh erb from the garden. he bounces off the walls like a hacky sack champion for a 1/2 hour then crashes on his favorite chair in front of the window.

he hasnt killed a mouse or bird since he started using, and now that he is getting some cardio in every day i think he may be getting in better shape.

you've seen cats run to a can opener noise before, this guy can here scissors cutting from the other side of the house.

why cant we all just get along and agree its the dirt people that are the real problem.

can some one tell me how the right way to start a potato from a potato? i just took one with some buds on it cut it in half tossed it under drippers hose. its looking fine but at work today the dirt people said i have no idea what i'm doing. that i'm killing myself with all those chemicals i put in the water and that if just used miricle grow i could probably make it through winter with out a big cancer growing in side me. dirt people are so dum, if hear they have had bumper crop again and just watered with water one more time i may feed them to my venus flytrap.