Lettuce & Greens always bitter

BettyCrackhead 8/23/2020, 7:26 pm

I am still a novice gardener in many ways, but I have come a LONG way. My tomatoes, beans, peas, watermelons & melons, zucchini & other squash are always on point!

However, my lettuces are always bitter. No matter the variety. No matter when I harvest. My spinaches are always fabulous...but my lettuce! Shocked

We eat a LOT of salads & I would LOVE to be able to get the majority from our garden.

What am I doing wrong?

**Scorpio Rising** 8/24/2020, 9:43 am

Hi Betty,

Are they bolting? Once they get tall and start to try to flower, leaves do get bitter. Lettuces are a cool weather crop, what time of year did you start the lettuce? I see you are zone 8, that’s pretty warm!

Welcome by the way!

OhioGardener 8/24/2020, 9:51 am

As SR said, Lettuce is a cool weather crop, and the main cause of bitterness in lettuce is heat causing it to bolt. Additional causes of bitterness can be too little water or insufficient soil nutrition. Since you are in Zone 8a, Lettuce would only be a very early spring or fall crop - it would be usable as a summer crop.

BettyCrackhead 8/24/2020, 1:00 pm

Scorpio Rising wrote:Hi Betty,

Are they bolting? Once they get tall and start to try to flower, leaves do get bitter. Lettuces are a cool weather crop, what time of year did you start the lettuce? I see you are zone 8, that’s pretty warm!

Welcome by the way!

Ok...like a knucklehead, I left out a LOT of the story. LOL!

I have been meaning to ask this for MONTHS! I actually tried to start harvesting in about mid-May before it really started hearing up & a the time, they were nowhere near bolting. I have since torn it all out (about a month or so ago) & fed it to our goats, who loved it.

I had it all in the ground by mid-March or maybe the 3rd week. I was careful not to let it go too long before harvesting & it was still nasty!

BettyCrackhead 8/24/2020, 1:04 pm

OhioGardener wrote:As SR said, Lettuce is a cool weather crop, and the main cause of bitterness in lettuce is heat causing it to bolt. Additional causes of bitterness can be too little water or insufficient soil nutrition. Since you are in Zone 8a, Lettuce would only be a very early spring or fall crop - it would be usable as a summer crop.

See my response to SR. I left out some pretty important info. Shocked

Everythign else in the same beds has totally thrived. I used some super soil & compost this season & production has been mroe than we can eat on everything else, so I have give away about 200 of pounds of goodies. Very Happy

That's why I am puzzled.

I wonder if maybe water was the issue. We have a watering system out in the garden, but prefer rain water when we have it... wonder if there just wasn't enough at the time.

BettyCrackhead 8/24/2020, 1:05 pm

And thank you both for your responses! It gives me things to look into! Lettuce & Greens always bitter 3170584802

**sanderson** 9/2/2020, 4:41 am

BCH, It looks like it's time to sow lettuce seeds in Zone 8A. https://gardenate.com/?zone=50

GloriaG 9/18/2020, 9:33 pm

BCH,

We are also in zone 8a, in Texas, and are just starting to plant lettuce seed. It will yield lettuce for us roughly December - April. After that I move the lettuce inside to avoid the heat. April in our area starts getting too hot for tender greens and by may they're tough and bitter.
Shade helps a little but not for long.

To have green further into summer we plant - Red Malabar spinach (a summer vine), Salad Burnett, Verde d'Taglio Swiss Chard, New Zealand Spinach, Sweet Potatoes (the leaves are great), and Kale.

Our summer lettuce comes from a small indoor hydroponic system. We pick about 4 small heads per week and supplement with the outside greens.

Good luck!

OldCrow 9/19/2020, 11:08 am

Speaking of Lettuce, what kind of temperatures are too high in your experiences? I've planted some in my raised bed and six in a bus box, those gray dish collection boxes I used as a bus boy 45years ago Smile

I have a sunroom connected to the house and on a clear 45F day it can easily hit 80s to 90s if I don't vent early. So I'm a bit lazy about moving containers all about, so how warmth can that lettuce be happy in?
OC

OhioGardener 9/19/2020, 11:56 am

OldCrow wrote:Speaking of Lettuce, what kind of temperatures are too high in your experiences? I've planted some in my raised bed and six in a bus box, those gray dish collection boxes I used as a bus boy 45years ago
I have a sunroom connected to the house and on a clear 45F day it can easily hit 80s to 90s if I don't vent early. So I'm a bit lazy about moving containers all about, so how warmth can that lettuce be happy in?
OC

According to the Extension Office pamphlet, "Lettuce is adapted to cool growing conditions with the optimum temperatures for growth of 60 to 65°F. At 70 to 80°F, the plants flower and produce seed. Lettuce can tolerate a few days of temperatures from 80 to 85°F, provided that nights are cool."

I grow it outdoors in a cold frame from October through March, with the automatic opener set to lift the top if the interior temp reaches 65ºF.

OldCrow 9/19/2020, 1:20 pm

OhioGardener wrote:According to the Extension Office pamphlet, "Lettuce is adapted to cool growing conditions with the optimum temperatures for growth of 60 to 65°F. At 70 to 80°F, the plants flower and produce seed. Lettuce can tolerate a few days of temperatures from 80 to 85°F, provided that nights are cool."

I grow it outdoors in a cold frame from October through March, with the automatic opener set to lift the top if the interior temp reaches 65ºF.

Excellent Data!! I missed this summer a few weeks when the temps got high to observe myself. But when we returned our remaining lettuce had bolted.

It was 75F in the Sunroom when I read your note, so I shuffled the lettuce inside quick like Shocked

But the Peppers and Tomatoes LOVE that temp!

GloriaG 9/19/2020, 4:32 pm

Average temperatures in our area are mid 70's f in April.
Well watered lettuce is fine in the shade at that temperature for us.

By May we get into the 80's f which makes the lettuce bolt and become tough/bitter.

OldCrow 9/19/2020, 5:21 pm

GloriaG wrote:Average temperatures in our area are mid 70's f in April.
Well watered lettuce is fine in the shade at that temperature for us.

By May we get into the 80's f which makes the lettuce bolt and become tough/bitter.

I suppose that since different types of lettuce have different cold tolerance then the same is true for heat tolerance.
For my first experience growing I went for Freckles Romaine Lettuce from MIGardener. I should get a good idea of it's cold hardiness before too much longer, first frost is probably tonight.
OC

GloriaG 9/19/2020, 6:06 pm

Yes, that's true. In fact some packages will say "heat tolerant" or "slow bolt"

We grow a variety:

Buttercrunch (tender bibb type early), Lau's Pointed Leaf (tender early), Grandpa Admire's (quite tender early), Rouge d"Hiver (red mid season), Black Seeded Simpson (mid), Italienischer (mid/late season), Salanova (many varieties - many can go to late season), Lollo Rossa (red mid/late), Slo-Bolt (late season), Cracoviensis (lightly mottled leaf mid/late)

We have found that the red varieties as well as the long pointed leaves (Romaine type) tend to stand up to the heat best.

I harvest a minimum of four heads per week all year round. When it gets too hot outside, I grow hydroponically indoors. The indoor temperature is a constant 77 f in summer and we have no trouble growing sweet lettuce.

I hope this helps.

plantoid 9/20/2020, 3:59 pm

Found this in gardening know how .

Common Causes of Bitter Lettuce Most gardeners will tell you that bitter lettuce is the result of summer heat; lettuce is known as a cool season vegetable. When temperatures rise, the plant snaps into maturation mode and bolts — sends out a stalk and flowers. It’s during this process that bitter lettuce is produced. This is a natural process that can’t be stopped, but it isn’t the only answer to what makes lettuce bitter. Too little water can also cause bitter lettuce. Those large, flat leaves need a large amount of water to remain full and sweet. Brown leaf edges are a sure sign that you lettuce is thirsty either from lack of water or root damage from close cultivation. Water regularly and well. Don’t let the bed become bone dry.

Read more at Gardening Know How: Bitter Tasting Lettuce – Why Is My Lettuce Bitter? https://www.gardeningknowhow.com/edible/vegetables/lettuce/bitter-lettuce.htm

I have my veg on a 03.00 hrs three minute watering via a time clocked misting sprinkler system I get some fantastic crops and no more bitter lettuce . Cut the lettuce and other salad stuff by 07.30 hrs before it starts to heat up dry out and put it in a bowl of cold water in the fridge .

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Lettuce & Greens always bitter