LETTUCE

Over 200,000 acres of lettuce are harvested in the US annually.

Lettuce growers face the difficulties of heat and light sensitivity throughout the growing seasons.

Our seed treatments will address those issues and help get the most from your crop.

As the industry leader in lettuce seed technology, we process more lettuce seed than our two most important competitors combined. Making matters more interesting, lettuce seed is among the most complex of vegetable seeds to process. This complexity arises from the physiology of the lettuce seed itself and the range of environments where lettuce is grown—differentials of more than 65 degrees Farenheit can be found in lettuce-producing areas around the world.

The heart of the lettuce bowl

There is no end to lettuce season at Seed Dynamics. We process lettuce seed 365 days a year. Seed Dynamics is located in the heart of the Salinas, California “lettuce bowl.” So we know lettuce. Lettuce is the basis of every salad. It’s a species that thrives in cooler weather with moderate moisture. Lettuce does not like extreme heat or dry conditions and is sensitive to light. Many lettuce growers, however, are located in hot, dry areas. Seed Dynamics can help.

Lettuce problem #1: Light sensitive

Lettuce is especially light sensitive. Light is required for some lettuce seeds to grow. When seeds fail to germinate in the dark, they’re called “photosensitive” or “photodormant.” Once they do emerge, to grow a field of lettuce with heads that are all relatively the same size (uniform), the seedlings must all spend an equal amount of time in the sun. Seedlings that emerge just 2 or 3 days later than the main crop may never catch up in size, not only because the others have a head start, but also because of the competitive effects of their bigger neighbors.

Lettuce problem #2: Heat sensitive

The right soil planting conditions, moisture and light, are not the only requirements for successful lettuce seed germination. Temperature also influences germination,  even when light is not an issue. For example, planting unprimed lettuce seed in constant light at two different germination temperatures, coastal verses desert (cool vs. hot) germination and subsequent stand establishment in the elevated temperatures can be inadequate.

Double whammy: Heat and darkness

A worst-case scenario can occur when a seed is planted in a light-deprived environment that is also exposed to high temperatures. When these two environmental factors interact together, germination can be inhibited even more. If these negative environmental effects are not alleviated within a particular length of time, the lettuce seed will not germinate consistently, if at all. The seed can enter a state of dormancy and may not germinate for a long time even if the environmental conditions become optimal. That situation is called “photodormancy” or “thermodormancy.”  This can have a devastating impact on your harvest.

The solution: Priming lettuce seeds

Of all the commercially planted vegetable seeds, lettuce is the most often primed.  Priming is a water-based process that causes all seeds to germinate around the same time. Priming also helps the stand establish itself faster. The result is a more uniform plant stand that helps ensure maximum cartons per acre at harvest.

Pelleting can be yet another problem—so choose your pellets wisely

Yes, we pellet lettuce seeds. And yes, the pellet itself can make lettuce seeds even more vulnerable to light and temperature. A pellet, after all, prevents at least some light from reaching the seed. Planting pelleted seeds beneath the soil surface (a recommended practice to keep the pellets wet and cool during germination) adds a stress that raw seeds do not encounter on the surface.

Choosing a pellet type that allows germination under stress environments is critical. You must also be sure the pellet can split and open evenly upon exposure to water. Not all pelleted seed products are equal. Seed Dynamics Gro-Coat® pellets have proven the test of time—and our own rigorous, constant quality tests. They’re designed to help growers solve the problems of mechanical sowing while at the same time address the issues of heat and photosensitivity.