I bend over to slice the central stem of a pretty, green, loose-leaf lettuce. White liquid pools up in a circle on the severed stalk. I hesitantly guide a leaf into my mouth to taste.
“Ptooey!” I spit it on the ground.
Why does lettuce turn bitter?
It has to do with the turning of the earth over eons of time.
In the spring, with each sunrise, the days become longer and the nights shorter. The temperature rises bit by bit. Winter turns into summer. This same natural progression has been happening year after year, millennium after millennium, since the world began. Over generations, plants evolved to recognize the subtle waxing and waning of the changing seasons and responded in ways that optimized their chances of survival.
Lettuce, for example, sends chemicals into its leaves that tell it to flower. My grandmother would have said the little guy is “going to seed.”
I peer down at the other lettuce plants near the cut stem. They look different than they did yesterday—taller. As the plants mature, an ancient process encoded in their DNA causes the stems to elongate and push skyward. Small flowers will soon form on top, grouping into clusters of tight buds, anxious to burst open. This process also causes the leaves to taste bitter.
I wonder if all of the lettuce is affected.
I planted several varieties last fall. From here I can see that all of this type look tall and are probably inedible.
What about the other loose-leaf varieties?
Certainly, all of the plants have been exposed to the same environmental conditions. However, some types have tendencies to flower earlier or later than others. I can select these types when sowing next-year’s crop.
Then I laugh out loud when remembering some of the latest research happening with plants. Science is uncovering an amazing picture of the social life of plants. We can’t see it, but these green guys communicate across distances with chemical gases.
Can one plant be telling another it’s
time to flower? It sounds absurd.
In my book, Baskets for Butterflies, I wrote about a small lizard named Lucky who could understand plant communication. Lucky heard a corn plant screaming, “Help, please save me from bugs!” When the insects attacked the plant, the victim made an odor, which it sent up into the air like a smoke signal. Lucky knew what kind of bugs were involved by the type of smell generated. Different bugs caused different smells.
This was written from a fictional perspective but inspired by emerging scientific research. Plants talk—to each other, to bugs, and to hungry lizards.
Are my lettuce plants telling one another that it’s time to flower? Who knows? But it’s definitely possible.
That’s all right because the last harvest of the season is seed for next year. I always leave the best and hardiest plants in the garden for this purpose. Since I have several loose-leaf types planted, they will cross-pollinate, which adversely affects the resulting seed. I must select only one variety to save and remove the others before they flower.
I walk down each row, slicing the stalks of all of the lettuce except one variety that has not yet gotten tall. I throw the others into the compost pile.
Then I stand there, wondering if my ‘culling’ of plants has caused a chemical panic in the garden.
How do you calm down and reassure a lettuce plant?
Ancient Native Americans sang to Corn, who, according to legend, was a living person. Modern science now sheds light on plant communication. Does this lend validity to the practice of song in the garden?
I add a bit of mulch to each row to cool down the soil, which may delay the lettuce plants from flowering. As I work, I find myself humming.