Our Process.

Lef greens are delicious for a reason. They’re fresh, they’re healthy, and they’re locally grown. A lot goes into each box of our greens, which is why a lot of flavor comes out. Before that flavor bursts onto your plate, these greens go through a revolutionary and technically advanced journey unlike any other. We’d like to give you a peek inside. Click a topic below to learn more.



On our farm, every baby leaf starts from a non-GMO seed planted in a soft bed of peat moss. It’s here in our growing channels that the perfect combination of peat moss and moisture creates the ideal environment for our seeds to sprout. From there, they are sent to our specialized seeders that allow us to plant up to fifteen different varieties of lettuces, mustards, and Asian greens. Our specially designed growing channels have air space below the peat moss that allows roots to grow. Once seeded, the growing channels receive a fine mist and make their way via a network of rubber conveyor belts to the greenhouse where they will be germinated (the fun is about to begin).



Strong seedlings are the foundation for healthy plants, and healthy plants mean you have delicious greens. When the seedlings are young they need a lot of extra care. Their roots have not yet expanded enough to absorb water, so we utilize overhead misters and heated floors that provide pure, clean water and heat right where these little greens need them. We think of it as a spa treatment for plants. After two days, the seeds are germinated and are ready to be lifted automatically from the lower germination level to the upper growing level where there is lots of natural sunlight to grow our healthy greens.



Here is where our greens spend the majority of their time. They arrive in the upper level of the greenhouse as freshly germinated seedlings, moving along a network of fingers that pull the growing channels from one end of the greenhouse to the other. This process takes roughly two weeks from seedling to the perfect height for harvest. Now, ready for harvest, the greens in our growing channels are pushed off the growing line onto a rubber conveyor that will bring them to be harvested. Seven days a week, 365 days a year, we are growing and harvesting fresh baby greens with the mission of getting them on your plate within 24 hours of harvest.


Irrigation, or watering, is the key to our state-of-the-art hydroponic system. Drip emitters deliver precise amounts of water into the base of each growing channel.Through gravity, the water flows across the roots, nourishing the young greens. This helps us reduce our water needs by providing water right to the roots, as compared to overhead methods which apply water to the ground first, then the roots. Anything the plants don’t use gets collected and reused over again.

Water and nutrient management is vital in our process. Because our system only has to replace water and nutrients that the plants use, we reduce our water consumption and nutrient loss by up to 90%. We use 1/10 of the water and nutrients to produce 66 times more baby greens per acre than traditional in-soil production.

Water Filtration

Not all water is created equal, which is why we use a water filtration system comprised of specialized sand that removes large particles. It keeps our water clean from debris, allowing us to reuse it many times over. And that means even less water usage.

Heating, Cooling, and Ventilation

One key element to happy greens is a perfect temperature. That can be a challenge in the hot summer months and the brutal winters of New England, so we utilize several key systems to help maintain the balance. In the summer, cooling pads help create the ideal growing environment in our greenhouse. And during winter months we use high-efficiency natural gas boilers to generate heat. Regardless of the time of year, our greenhouse stays at a comfortable 75F.

Air movement becomes particularly important in regulating temperature. We vent through the center of the greenhouse, allowing us to draw filtered air in through the sides of our facility, and push hot air out the top. This allows us to keep the greenhouse evenly ventilated no matter what month it is.

Carbon Dioxide

Carbon Dioxide is a requirement for plant growth. In the winter months, when we’re preserving as much heat as possible, our greenhouse ventilates less frequently. Overtime the C02 levels drop, resulting in lower yields. The good news is, in the winter months we use our 97% efficient natural gas boilers to heat. With a specialized machine we can collect CO2 emissions and disperse them in the greenhouses right where the plants need them. Using permeable translucent tubes under the growing areas, the plants have access to the C02 needed to grow. By capturing and reusing our own emissions, we reduce our carbon footprint, while creating a perfect growing environment. Technology at its best, a win-win for the farm and our environment.

Supplemental Lighting

Growing in greenhouses allows us to generate huge amounts of heat and naturally capture about 80% of light from the sun. Most months of the year, this does the trick. However, in the winter months when light levels drop, we utilize supplemental lighting. The goal is to provide just the right amount of light to have healthy plants. With advancements in lighting technology, we can save energy and produce more light for our greens, so they taste as good in the winter as they do in the summer.



The two-week growing journey is complete and it’s time for harvest. Once our baby greens are ready to harvest, our growing channels move from the growing lines onto a conveyor belt and right into our state-of-the-art cooler. By harvesting our greens at a chilly 35°F, we rapidly remove heat and lock in the fresh taste, increasing post-harvest performance, extending shelf life, and preserving the deliciousness.

Conveyor belts can be made out of a variety of materials. These can include thermoplastics, metal, rubber, fabric and leather. The most popular material is a rubber composite because it is flexible, resistant, smooth and seamless. To learn more about conveyor belts, go to californiaindustrialrubber.net.

Once in the cooler, our greens are sent through our hands-free harvesting machine. It uses a double-blade system to cut the product at the perfect height. From here the greens are gently moved from one conveyor to the next until they reach the mixing lines. This is where the magic of our unique blends begins to take shape. Each batch stops and waits a specific amount of time before dropping to create a delicate layer of greens, so each bag you open has a precise blend inside.

From here, the greens move up a conveyor to a scale where they are weighed and accurately portioned out for each bag. If you don’t see terms like “washed and cleaned” or “triple-washed”, it’s because our baby greens are protected from field contaminants, such as dirt, insects, manures or harmful pesticides.



Once the greens are harvested, they’re ready to be placed inside our distinctively branded packages. The greens are weighed for food service or retail. We use special scales that collect the greens into dozen or more buckets – once a batch reaches the correct weight, it is dropped below and immediately sealed for freshness.

Packages then get dropped into our custom-made boxes, which use less cardboard and allow for increased airflow. This allows our product to maintain the cold chain after harvest, keeping our product tasty and fresh up to seven days longer than California-grown greens.

The final step is our quality check, which includes a full scan of every package of fresh greens. This ensures that, before a single package leaves our facility, its weight is accurate. But more importantly, the scan makes sure each package is 100% clean and free of debris. Nothing but fresh baby greens inside.

We also verify the labeling by inspecting the lot number and name of product, as well as the weight and the seal. This is our commitment to the customer; we do the checking so they don’t have to.


Food Safety

Sanitary cleaning practices are at the core of every food-safe farm. While most farms struggle with the ability to keep things consistently clean, at lef, we take cleaning very seriously. We have a unique opportunity to provide a safe and healthy environment for our greens to grow throughout every step of our process. Once the roots and growing media have been removed from the growing channel, the byproducts are sent to our composting area where we have the potential to compost our waste and repurpose it. Better than a landfill, isn’t it? Each growing channel that grew the last batch of greens is pressure washed and sent back cleaned and ready for the next fresh batch of seeds and growing media. Our commitment to clean doesn’t stop there, we also thoroughly clean our greenhouse and harvesting room daily. From top to bottom, we are committed to your safety by keeping our facility rigorously clean and sanitized.


Locally Grown, Non-GMO, Hydroponically Grown, Pesticide Free

Road Trip Lēf Farms is a local New England grower of fresh salad greens very few mouth-watering
salads start with a
seven-day road trip.
Time Zone Lēf Farms is a local New England grower of fresh salad greens fresh lettuce grown in
another time zone
isn’t fresh lettuce.
Stopwatch Lēf Farms is a local New England grower of fresh salad greens fresh should be measured
with a stopwatch.
not a calendar.
Week-old Lēf Farms is a local New England grower of fresh salad greens would you call
week-old lettuce fresh?
neither would we.
Vintage Lēf Farms is a local New England grower of fresh salad greens vintage:
Aged Lēf Farms is a local New England grower of fresh salad greens decidedly not
aged to perfection.

Did you know that more than 95% of the greens most people eat come all the way from California, Arizona and Mexico? That’s not exactly nearby, nor is it a recipe for freshness. Even many so-called “local” greens are really West Coast-grown — they just get new packaging slapped on at an East Coast repacking operation. After they’ve taken a long ride in the back of a shipping truck.

We think greens need to be grown where they’ll be eaten, so they hit your plate at the peak of freshness. That’s why all lef greens are hydroponically grown right here in the heart of New England. They’ll get to you within 24 quick hours of being harvested. And they’ll change your perception of just how fresh, healthy and flavorful local greens can actually be.