Lettuce (and greens) the OPPOSITE light schedule to Pot

Years I have been trying to figure out why the one good lettuce crop I had grew from fall to spring and I have never had lettuce that did not BOLT since…

Well, it turns out that lettuce is every bit as sensitive to the number of hours in a day as MJ is - but in REVERSE!

Things that make lettuce “BOLT” are:

  1. Over fertilization, dried out soil, anything that threatens the plant.
  2. The eventual age of the plant, 3 to 4 months is about it usually but they can go longer
  3. TEMPERATURE - anything over 80 degrees f is likely to cause lettuce to bolt, but this is not the main trigger ~

The one thing of all that I finally found articles about is that IF THE LETTUCE PLANT DETECTS MORE THAN EIGHT HOURS OF LIGHT in a day (sound familiar?) the plant will assume it is full summer (!) and will be switched over into flowering mode…

Which is exactly the reverse of Marijuana but it explains everything

Have you ever wanted to grow excellent salad greens at home? If so I hope this gave you a monstrously big clue that it took me years to put together. There is even mention of a lettuce plant that was purposely allowed to get over a hundred degrees f. daily but with the light cycle maintained at 8 on, 16 off it didn’t bolt for 135 days.

Imagine how much free munchies that is…

~the one thing I never controlled was the hours of light, how could I have guessed?

And all it would take is to plant it at the same time as a certain “FLOWERING” cycle is initiated for optimal use of grow space. It sounds like a complete biological oxymoron that at one and the same time a Marijuana plant is triggered into full flower - yet salad greens go into full blast vegetation doesn’t it?

And yet according to a number of studies I found this is the nature of Cabbage, Lettuce, and several other “Cold Weather” crops. The thing that makes lettuce bunch together tight and yet with big full leaves is that it is in vegetative mode. It bunches tight also to protect it from freezing! But the hot part of the year is its one chance to propagate, so it blossoms when the days get long enough… Mystery solved! :alien:


We grow lettuce here on the Central Coast and it’s the most satisfying plant (other than MJ) to grow. We usually do Romaine and Red Leaf lettuce and I have enough growing now to feed the entire neighborhood lol.


Over the last dozen years I have given away thousands of dollars of fresh goods just so they would not go to waste. I still have bags of frozen tomato slices in my freezer, and peppers & other goodies!

Fresh is best!!!


I just never thought I would need a darkroom unless I was growing 'Shrooms. Mushrooms I don’t risk because there are so many poisonous varieties. The obvious ‘other’ variety will never be legal, and we won’t discuss here.

But the lettuce I do remember was fabulous looking. I’d also like to get some swiss chard going, that’s another non-success for me

What I’m reading now is that the effective “CUMULATIVE LIGHT” limit is 12 hours for lettuce. How that stacks against herb I dunno, 'M kinda burned out. There are a lot of similar but ambiguous articles out there.

If it is 12 OUT OF 24, then there’s a total that must be minded.

If it is 12 CONTINUOUS, and then 2 OFF - and then it can be repeated, this is news indeed…

I saw something like that, and I thought: “My timer is 24 hour based, how would I do 12, 2, 12, then another 2? Impossible!”

But it could be set to ten on and two off twice. This is a puzzle, and I am creating a new grow room to move my Durban’s into so that I can experiment with these lettuce ideas. The new grow room is a closet that is totally hidden with no chance of anyone having to pee and finding a group of plants that would get me in massive trouble since I can lock the room.

The lettuce farm will be in the original grow-bath-room :ok_hand: so that an occasional visitor can see the “Grocery” plants. That will settle any suspicions and also may just turn into a cash series of ideas such as nailing down all the problem veggies I ever wanted.

But anyway, the entire nine meters are being reshuffled.