Brainstorming: Corn formula and best growing setup

[Luches]

Hi folks,

If I am not mistaken, a few members (including myself) are interested in growing corn hydroponically. So, why not put together as much info as we can get from many sources, personal experiences (if available) and eventually try to get a little "file" about the topic?

Formulas and nutrients: as some people may have noticed, commercial products from shelf are not my cup of tea for 2 reasons: A. I can't buy any of the commonly known products at my place. B. I am specializing in developing and mixing nutrients from components and raw materials. Actually just pointing out kind of a "personal conflict" here. If some people are suggesting products or mixes that are based on commercial products, I have no problem with that, but I can't participate to such debate or quest. The only thing I may do is analyzing the formula and reproducing a similar nutrient.

Setups: Let's find out what kind of setup or system (as well as media) is most appropriate and adapted to grow corn.

I have done some net searching yesterday and was pretty amazed with this simple ebb/flow Perlite based setup, even though I am no fan of Perlite: Hydropond Corn

To be continued with more adds and material ...

[GpsFrontier]

I don't really have much to offer this thread about growing corn at this point, except I am very interested in this also. I can get the commercial hydroponic nutrients here even though I need to have them shipped. I would love to make my own (and hope to in the future) like Luches does, but I need to do things as funds are available. I also understand it is a precise process. Though I have no doubt I can handle that, for now I will need to stick to the commercial stuff until I can afford the equipment and find the suppliers of the raw materials.

To me, my concerns mostly revolve around it being cost effective to do so, the beat growing medium to use and how deep it should be, flood and drain versus drip systems and how much product you should expect from it. During the summer it is common to find 4-6 ears on sale here for $1, though it is much higher during the off season. Of coarse quality will be much higher growing your own (no question).

I wont be growing it real soon but want to learn as much as I can to make the best decision on the best way to go about it. For me I have not used Perlite or Vermiculite as a growing medium in hydroponics yet but have experience with them in regular soil. They may actually be a preferred growing medium to me because I would not need to have it shipped to me. The nearest hydroponic supply store is about a 3 1/2 hour drive (one way). But I can get these at just about any nursery in town. I have not considered them before because until now, all my systems were Ebb & Flow (flood & drain) and it simply wont work for that type of system (at least my design).

[Luches]

I've done a little research and maths about a adequate formula for corn. This is based on NPK-content on plant residue analyses. I've then transfered these data into a "modern concept" of nutrient composition:


Formula without guarantee or if you prefer: WITHOUT COVENANT AGAINST GRANTOR'S STATEMENT



Explanations: Grains contain much more nitrogen than forage and other parts, that is why I suggest higher N-content in the fruiting formula. 2. Forage and cobs have very high K-content, that's why K-content should be high in the formula. General growth-rate of corn is rather high, - and that's why a rather high feeding (yet not a aggressive) strategy should be appropriate. But again: this formula still reflects my general tendency for economic formulas, that do not stress plants into excessive growth, but rather simulate a natural environment. Both formulas have relatively high Phosphorus and Calcium content (50 ppm of P and 140 ppm of Ca would be sufficient), this to assure enough P- and Ca content in case the formula is used in notably lower concentrations.
PS: I've also added a comparative formula for tomatoes, that illustrates and helps understanding the process of getting to a nutrient formula - based on a plant analyses.

[Luches]

Here's the setup I plan to use.


Yeah, I've also designed and build a setup for corn in no time, based on ebb and flow system (as seen @ youtube but with double bed and extra stand). It is actually build from parts I've used earlier with other setups - even the reservoir (180 Liter) is a used-one.





The upper "beds" will be filled with 3 different media, first (bottom to top) basalt gravel (very cheap here), pea sized river gravel followed by a bit finer gravel. This concept assures best drain downwards but enough moisture for seedlings small roots at the top. A very small and economic pump will do the job of fow/ebb cycles. 400L/h and only 5.5 Watt is already tested to be sufficiently powerful.



I didn't specify any dimensions here, as the design is- and should be -put together with existing parts. The frame (stand for the bed reservoirs) should be adapted to reservoir and other sizes.

For any questions or more techs and specs, do not hesitate to ask!

[GpsFrontier]

I am wondering a few things. The corn stalks I am familiar with can reach 6 feet tall. with that in mind I was wondering if you were planing a support system so they don't topple over. it looks as if the growing containers that will support the plants are about 6-8 inches deep. I was also wondering how many plants you were planing to grow in each container. I see in the video they seem to be just a few inches apart but I have no experience with corn yet.

I understand your purpose of growing corn is different from mine. I don't know how many plants would be able to grow that close together and if it would be economical for me. I did see something in the background of the YouTube video (about 1/4 way through it) that gave me a similar Idea. The mini pool with plants growing in it. I don't think I would use that as a flood and drain system because of how many gallons it would take, but as a drip system I think it would do nicely. Provided the growing medium did not cost an arm & leg.

I have not done the research on it (even though it wouldn't be hard) but as I remember you get somewhere between 3 and 5 ears per stalk. Considering how inexpensive it is here during the season, the cost of operation is of big concern to me. If it costs much or more to produce than to buy it wont be productive for me to do so (even though freshness would be a plus). Also, I would guess that corn is a heavy feeding plant.

[Luches]

Originally Posted by GpsFrontier

I am wondering a few things. The corn stalks I am familiar with can reach 6 feet tall. with that in mind I was wondering if you were planing a support system so they don't topple over.

Right, except if you are planting a "dwarf" variety, which is surely an option I'll consider. Otherwise, I had a support system in mind and @ this picture you can see it. The lateral "Ts" will be used to fix a support ring.



Just imagine a reduction fitting 1.5" to 1" and a 1" ring all around the stalks. A bit higher as shown of course.

Originally Posted by GpsFrontier

it looks as if the growing containers that will support the plants are about 6-8 inches deep. I was also wondering how many plants you were planing to grow in each container. I see in the video they seem to be just a few inches apart but I have no experience with corn yet.

Well it's known that in hydroponics you can plant any crop (rice, weat, barley or corn) very narrow. Unlike in soil, where there is need for much more "root space" and where nutrients are (or if you like, uptake is) limited. From this perspective the ratio of space vs. yield is much higher as in soil.

The "personal economics" (as yours) may be seen from a different perspective and having a different outcome, though... but do we really do this maths, every time we build or plan a setup or before planting a vegetable or crop? On the other hand, I wouldn't anyway plant any "consumer corn" in this way, as this kind of corn is even cheaper here in Thailand as in the US, where it is supported (like mad) to protect the national market.

As I'll grow heirloom and rare varieties from Mexico and Peru, etc. (hope the seeds reach here soon and safely) I will probably use my first unit for testing purposes (both, my newly designed formula and the setup) an I'll also compare growing in soil (probaly next to the setup). So for me it is a win-win thing anyway.