It would seem that the roots need more room. You will need to transplant them into their final growing media. This is an interesting learning experience. I will do more research to see if we can find an exact solution to the problem, but here is what I have so far.

Excerpt from: Arizona University (http://ag.arizona.edu)
The three stages of early development are germination, post-emergence, and transplant. Germination should occur within one week of seeding, post-emergence is generally 5 to 12 days, and transplanting should be done between 12 and 14 days from seeding. Once true leaves appear (during post-emergence), seedlings should be transferred into larger growing blocks (pots) from the original seedling cubes, then evenly spaced to maximize light to each plant, without any crowding or shading. The transplants must be spaced so as not to touch one another, and may need to be spread several times during their growth. If crowded, the plants will become spindly. A good transplant is one that is as wide as it is tall. If plants are somewhat “leggy”, with long stems, they can be transferred into the larger blocks with their stems bent 180° , so the original cube is upside-down inside the larger block, and the main stem forms a “U” shape, emerging vertically upward from the block. Tomato plants readily grow adventitious roots from the stems if given the opportunity, producing a stronger plant with more roots. Adventitious roots will grow from the bent stem inside the block.

Transplanting into the final growing media should be done before any flowering. The final growing media should be properly leached and moistened and be at the proper temperatures before plants are brought in. Plants should be irrigated with nutrient solution immediately after moving.

The spacing of tomatoes in hydroponic systems can be much denser than in soil. As little as two square feet per plant (0.2 square meters per plant) have been used with good yields and quality under high light conditions. Spacing is a function of sunlight, so in areas of lower light wider spacing should be applied.

Indeterminate tomatoes must be trained up support strings immediately after transplanting. The strings should be hung from horizontal wires, which are connected to the frame of the greenhouse. These wires will need to support hundreds of pounds of weight, as each mature plant with fruit may weigh 20 to 30 pounds (7 to 14 kilograms). Additional vertical poles can be added to help support the horizontal wires. The wires and strings should be put in place before any other paraphernalia is brought into the greenhouse, and should be at least 10 feet (3 meters) above the ground. The strings should not be re-used, however, a variety of clips are available which can be sterilized and re-used. As the plants grow, the strings are unwound from their hangers and moved along the horizontal wire, effectively “lowering” the plants without breaking them. Mature indeterminate tomato plants may be 40 feet (12 meters) in length, and can grow much more.

My motivation was originally an acquaintence who started growing micro greens about 20 years ago and has built the business to a million dollar business. He is about to retire and will be selling his equipment and accounts for about $360,000. With only 20 customers, I was impressed by the claims that he makes that much profit and still cannot keep up with the demand for micro greens.

So, I started a garden, with lettuce, tomatoes, okra, corn, beans, carrots and various other vegetables to get my feet wet with gardening. As a side note, my wife was always the one interested in gardening while I was working in Information Technology and was away from home much of the time. Now that I’m not working, I am able to enjoy the freedom of doing things I love to do also.

After embarking on my first real garden, I decided on building some greenhouses and a compost bin. I found a man who had lots of half-round professional greenhouses he didn’t need any more and he allowed me to disassembly about 2,000 square feet of greenhouses which fits nicely in my current .25 acre rental.

At this writing, the greenhouses are erected and the compost bin is built. The plastic still needs to be installed to cover the greenhouse and I’m learning about composting.

While thinking of ways to maximize the space of my greenhouses, grow and harvets the maximum crop yields with the maximum profits, I first decided on the square foot gardening method. This method uses 6 inch tall boxes with 4×4, 4×8, 4×12 grids where you can plant 16 different crops in a 4×4 container.

The difficulty I had with this idea is that you have to build the boxes, buy the vermiculite, peat moss, and blended compost to fill the boxes. Although this method required less work after setup, the cost seemed to be prohibitive for me in growing the quantitiy and quality I need to profit from the business.

In the process of building a supporting structure for the square foot garden boxes, I realized the yield and space utilization didn’t seem to fit my goals. So I start researching hydroponics.

At the grocery store, I noticed the significant price difference between organic lettuce and hydroponic lettuce. The price of the higher quality hydroponic lettuce was over double that of mere organics.

For my hydroponics system, I started with a coupld of 10′ plastic gutters, some 1/2″ poly tubing, a 20 gallon black trash can and a water pump. The concept for an expandable nutrient film technique (NFT) system is sound, but currently, the pump I have is too small to achieve the volume of nutrient flow I need to make the system work.

My blog will detail the steps taken and the progress made as I continue with my hydroponic adventures.