Getting the red to come out in lettuce
It's been a while since I've posted but things have been going pretty well overall. My lettuce production is moving right along.
One question for the group here is about red leaf. I have really struggled to understand why my red leaf starts out pretty red but then fades to green moving into maturity. I can't figure out if it is light or nutrient related but I'll let you know what I've got for the system.
1. Using Hydro-gardens commercial ferts (they have been very stable and reliable)
2. I run 1000 watt MH bulbs for 14 hours/day (tried 17 or more but the redness didn't improve)
3. Lights are about 34" or less from tops of heads and are cooled to keep temps down. Have experimented with closer setups down to 24" but saw no improvements.
4. Bulb light temp spectrum is 5,000 K for growth. Had some at 4200 k but saw no improvements.
4. Keep nutrient no higher than 70F
5. Keep EC around 1.2 and pH between 6 and 6.3
I have messed with higher EC's but it gave me tip burn bad so I went back down to 1.2 an all is well.
I will say that the only time I saw the redness really start to pop out is when my res was exhausted and needed to be changed. I unfortunately didn't get an analysis of the mineral content so I'm not sure what the difference was. I had to move quickly because I saw issues starting to develop in the Romaine tips. After the change to fresh nutes, the romaine improved and the red head lost its redness. Hmmmm.
All thoughts would be great.