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Old 03-09-2010, 08:16 PM
GpsFrontier GpsFrontier is offline
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Join Date: Mar 2009
Location: Lake Havasu AZ.
Posts: 1,855

Damm Bird... eat or damaged more than half my lettuces...
Ahh.. man, bummer. We have a lot of birds around here but no problems with them yet. Although if my plants are too close to the ground without any screening around them, the rabbits here will get them if there within reach.
One question I have... as the oasis keeps wet all the time... its supposed to hold air in it too... should I use a timer to let it dry a little more and get more air?
Well, this was my original concern with the cubes sitting directly in the tubes. The plants will do better if the roots are not completely saturated all the time. Although as I understand it, lettuces plants don't mind that as much as other plants. That's one reason why they do very well in the water culture type systems (like in the youtube video you posted). A timer will work to a point the way you have your system set up right now for that purpose, but once the roots grow outside the oasis cube, it wont work well. The cube holds moisture so the roots inside the cube will be fine, but the roots outside the cube will dry out rapidly.

When the pump is shut off, it will take time before all the water is drained off the bottom of the tubes (unless you have it set at a steep angle). So the roots that are sticking outside of the cube will get some moisture before drying out, but at the same time the cubes will be sitting in the water also. So the cubes wont actually have a chance to dry out until all the water is off the bottom of the tube, and that is when the roots outside the cube will start drying out rapidly (like in 5 minutes or so). That is why I suggested inserting baskets into the openings, and placing the cubes in the baskets once the roots are long enough to reach the bottom of the tubes. I would just want to make sure the baskets rest around 1/2 inch above the water level.

Also if you can close up the openings around the base of the plants you wont have as much evaporation, and the dangling roots will be able to hold onto the moisture better. Mainly because you will be helping to trap humidity in the tubes where the roots are. This would be much easier to accomplish using baskets in the openings. It would also help keep any light out of the openings, cutting down on algae growth.

P.S. Thanks for the link to the Oasis Rootcubes, I was not able to tell what material they made of from the description. But I have been meaning to e-mail them the question, just hadn't gotten around to it yet (maybe tonight). It seems like it will be just about the same cost as the rockwool cubes at $8.95 for 100 1" cubes. The oasis cubes brake down to $6.97 each when ordering 20 sheets of 104 cubes. It probably will be a buck or two higher when only ordering one sheet at a time, bringing up the actual cost to just about the same as the rockwool cubes. It also says it Holds almost 40 times it's weight in water, so I am not sure how much better at aeration it is than regular rockwool. But like I said, I plan to e-mail them soon. I will probably buy some the next time I need starter cubes, that way I can compare them.

I know you already fixed your pH level, but I just thought I would fallow up and post what they replied to my question (I got the reply Monday morning).

My question
"There is some confusion in the proper pH level for tomato's in the information I have found online. I see recommendations as low as 5.5, and as high as 6.5, Can you tell me what the correct information is? Is it variety specific? Also will the flowers fall off and leaves start to curl if it is off by .5 or so?"

There reply
"The ranges you have been seeing are normal. Many people attempt to get their pH down to exactly .1 or .2 from what they believe is ideal for whichever crop they are growing. Sometimes this can harm more than help. Plants respond to a range of usable pH which inter-relates to nutrient availability. This means that nutrition is available within the range of 5.5-6.5. When you are mixing up your nutrients, if your initial reading after mixing is within that range don't bother adjusting the pH as sometimes the adjusting products used can cause some issues, with nutrient availability. Tomatoes will feed within that range well, just be sure to supplement calcium to prevent blossom end rot. Fluctuation of your pH can occur, and this is a damaging occurrence so help prevent this by using the best possible starting water, and the least amount of pH adjusting solution necessary."
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