Backyard Aquaponics
A place to discuss aquaponics

I know I keep coming back to the same theme but a reply to a previous question inferred that my PH might never drop, if that is the case I would like to know if anyone has been successful with lettuce even though their PH was high. I've got about 45 -50 nice looking lettuce in my flow tubes but they have all bolted and taste really bitter. (by the way my PH is stuck at eight) We are just coming to the end of summer and that is the probable cause of the lettuce bolting. Our plans for the system sort of revolved around growing lettuce so I would really like to get a handle on this issue.

What type of lettuce did you plant?

http://agsyst.wsu.edu/WinterLettuce.html

If you haven't shaded the channels you might consider this for next Summer. You should be able to grow lettuce more easily this fall with the cooler weather.

Regarding your question about pH - yes, it's been done. I have raised lettuce in aggregate beds with a pH of around 7.8 to 8. Didn't seem to be any problem at the time although cos types seem to grow the best for me and I live in a cool climate which gives me some help. I'm pretty certain TCLynx has raised lettuce at high pH as well and she is in Florida.

additional information with Summer lettuce suggestions is here
http://www.naturalhub.com/grow_vegetables_cultivars_lettuce.htm

Thanks Scotty, very encouraging. I've got net shading but it was very hot last month and the month before even hotter, so that must be why the lettuce bolted. Things cool down pretty quickly round here and should be ideal for growing lettuce throughout our winter months. What do you do with your system through the Oregon winters?

We have mild winters so I just keep growing. Everything grows slowly because there isn't much light (mostly overcast here). We get occasional cold spells down into the teens or more likely the twenties. I just let my system go down to slightly above freezing and keep the water moving (I rarely heat even during these cold spells). Sometimes the top of the growbed will freeze but never more than this. Main battle around here is with condensation since half the system is in a greenhouse - always keep an oscillating fan running to help with this. Of couse with this kind of climate and light I grow leafy greens no fruiting plants during the winter . Not much like Lima.

Cheers