Back From Vacation

I just returned from vacation and I'm glad to see that my plants are growing and look healthy.  Before I left on vacation to Alaska last week, I moved 6 lettuce plants and 2 fennel plants from the germination tray to DWC (Deep Water Culture) hydro units.  I made sure not to move anything that did not have roots visible on the outside of the rockwool cubes.

Before I left, the tubs were set up in a solution of about 450 ppm with one 400 watt equivalent fluorescent light fixture illuminating each tub.  When I returned, I was happy to see significant growth, especially the lettuce.  Lettuce can grow with fairly weak nutrient concentrations, but it seems that 450 ppm is a bit weak for herbs.  The cilantro plants looked a bit purple on the edges of the leaves, and one leaf was curling.  I think it may have been due to a nutrient deficiency.  I pruned the bad leaves, and changed out the nutrient solution in all the bins to a little stronger solution.  I mixed the lettuce solution to about 600 ppm, and the herb bins to about 700 ppm.  This is a bit on the low side, but within the parameters for each plant.  If it looks like I am having nutrient deficiencies, I can further raise the nutrient strength.  After a day, the cilantro is looking a bit better.  Also there does not appear to be any tip burn, which is a concern any time I increase the nutrient concentration.  I did lose a couple of purple basil seedlings due to lack of water, and a spinach due to premature bolting (too warm and too long in the germination tray), but my thyme and oregano plants appear fine.  Here are the plants as of today.

My carrots and radishes have developed a fairly large population of algae on the growing medium, but the plant health looks ok.  The algae probably began due to covering the bins with plastic for about a week with lots of light and no air circulation.  I'll just see how these do.  When I changed out the solution in these bins. there was a 12" root hanging through a hole in the upper bin.  Also, the roots have grown like crazy on all the other plants.  These roots were not visible on the outside of the net pots before I left on vacation a week ago.

Lettuce: Red Sails

 Kale

 Lettuce: Buttercrunch

 Cilantro

Radish

So, That's it for now.  The next hurdle will be keeping everything alive while I'm gone for turf management classes at Rutgers for 3 weeks, but we'll cross that bridge next week.

Seedling Pics and DIY Lights

Well, I'm still waiting for my seedlings to grow their roots before transplanting.  I moved some of the seedlings into the hydroponic units to see if they were ready, but it quickly became obvious that they were not.  After a week of sluggish growth in the DWC units, I moved them back into the germination tray to mature further.  They are now growing vigorously and do not appear to have suffered much from the early transplant.  

As you may see, I got my LED lights in the mail, and they are sweet!  I paid $30 each for 2 on ebay, and I would say they were worth the money.  I have to be careful when I plug them in or I can blind myself or others (sorry wife), so pretty bright.  I have also been perfecting my CFL light fixtures by adding lights and experimenting with different configurations.  I also found some other inexpensive solutions for building cheap CFL grow light fixtures.  The art of sheet-metal-origami and the risk of electrocution keeps me entertained while I wait for the baby plants to mature.  It also helps to make sure that my plants will have plenty of light when they move to their new homes.

After trying a few methods including lamp fixtures, shop light fixtures, and extension cords, I found 2-packs of power strips at home depot for $5 so I settled on this design for cost, flexibility of light placement, and ease of construction.  So, a unit like this puts has 400 watt output and uses about 100 watts.  Total cost to build is about $20 including bulbs.  Also, zip ties and baling wire are indispensable.  I now have enough light fixtures to cover 4 hydro units, 1 germination tray, and my new little experiment.

Here, I have 2 manually irrigated hydro trays growing radishes and carrots.  I set these up as wick irrigation units.  Each tray is actually 2 nested trays.  The inner tray has holes drilled in the bottom and is lined with wire screen, while the outer tray holds about an inch of 50% nutrient solution.  The trays are filled with perlite, which wicks moisture from the outer reservoir tray.  The theory behind this experiment is based on the fact that the root that we eat is a large taproot that is meant to grow quickly and store nutrients so that the plant has plenty of stores for difficult times.  The taproot needs to dig itself deep seeking out nutrients from the lower area of the soil profile, so if nutrients are too readily available to the plant, the taproot does not have the impetus to grow deep and large.  The wicking system should supply more nutrients to the deeper levels of the soil profile, while still providing the upper levels with sufficient nutrients.  We will see how it goes.