Garden & Greenhouse


Stop Torturing Your Taste Buds – Growing Lettuce and Herbs Hydroponically!

Posted January 7th, 2013 by Garden & Greenhouse in , ,

CS Sam NFT08

Have you walked down the produce aisle? Pretty bleak, isn’t it? Chances are that the “fresh” vegetables that you see this time of year have traveled thousands of miles to your local store. Often harvested prematurely and leaving behind most of the flavor and nutrients, “truck-ripened” produce is unfortunately the status quo for the season. The fact of the matter is that the flavorless, colorless veggies available this time of year never stood a chance against hydroponically grown produce.

Just smell the tomatoes. You can tell without even tasting them that they will be flavorless. Not only are they harvested before they are at peak ripeness, but the varieties that are planted are not chosen for flavor! These forlorn fruit were chosen for uniformity and shipability only. Flavor is an afterthought. The farmer’s only concern is that his crop “matures” at the same time and can withstand traveling in a crate across the continent.

The same goes for the lettuce, peppers and cucumbers. I will bet that the plastic vegetables your kids or grandkids have in their play kitchen taste just as good. It does not have to be this way. You can take charge of your own food destiny and learn how easy it can be to have fresh vegetables in your home no matter the CS Sam NFT05season. Do you have a corner of the basement available? How about a spare closet? If so, you are only a few steps away from enhancing your quality of life by growing your own local, healthy vegetables year round. Your produce shouldn’t need a passport to get to your supermarket!

Recently, I wrote about some misconceptions that are often associated with hydroponic vegetable cultivation. I also touched on my favorite style of hydroponic growing, the nutrient film technique, or NFT method. This article dives a bit deeper into NFT growing and will focus on lettuce and herb production from seed to harvest. I want to convey just how easy it can be to grow hydroponic vegetables year round no matter your climate. A prudent grower starts by choosing varieties and cultivars of seeds that are proven successful. You will be way ahead of the game and have fewer problems throughout the growing process if you choose disease-resistant seeds. Whether you are a master gardener or a novice, learning the pros and cons of the various seeds available will make you a more successful grower.

Heirloom seed is becoming quite popular. There is something nostalgic about growing seeds handed down for generations. However, these seeds often do not have a natural resistance to diseases and pests. Harvests may be less consistent, but heirlooms are so flavorful! I love heirlooms but the majority of my seeds are chosen based on disease resistance and temperature tolerance.

Once you have your seeds chosen, it is time to plant. NFT lettuce production generally starts with sowing the seed into a propagation mat. This mat consists of small rockwool cubes that are preformed to fit into a standard 1020 flat. The cubes break apart individually when you are ready to transplant the seedling into your system. Rockwool cubes have great moisture holding capacity, good aeration, are clean and easy to use.

To germinate, lettuce seeds need light and cool temperatures of about 53° to 68°F. The rockwool should stay moist but not become overly saturated. Your seeds will germinate in 3 to 7 days and be ready to transplant into your NFT system after about three weeks. It is time to transplant when the roots start to emerge from the bottom of the rockwool and are approximately an inch in length.

Once transplanted into the NFT system, young plants need a good quality, well-formulated nutrient solution. I use a complete fertilizer blend called CNS17. This fertilizer is made up of all of the essential nutrients necessary for plant growth and is considered “complete.” Nutrient solutions can be heated in cooler climates or chilled in warmer climates to maintain proper temperature for growth. The ideal solution temperature is between 60° to 68°F. Most varieties of lettuce will produce about 10 to 12 crops per year in an NFT system. The average time in the NFT system is 4 to 6 weeks, but this is dependent on the season and variety grown. This timeframe does not include the 3 weeks seedlings spend in the propagation area before being transplanted into the NFT system.

If you have never tried hydroponic lettuce, you should. The shelf life, flavor, juiciness and crunch are amazing. My kids will actually have lettuce salad for an after school snack plus is it very healthy and delicious. We grow and market ours as “locally grown” and “pesticide free.” One of the latest trends in hydroponic lettuce marketing is selling what is called “living lettuce.” This lettuce is actually harvested with the roots still intact. The roots are neatly trimmed and put in a specially designed clam shell or sleeve with a little “nest” for the roots. This lettuce can stay fresh for up to a month!

Another easy way to get your feet wet with hydroponics is by growing NFT herbs. Herbs fall into two categories: warm season and cool season. Warm season herbs include basil, coriander(cilantro), rosemary, sage, oregano, marjoram and Italian parsley. The cool season herbs include mint, chives, garlic chives, lemon balm and arugula. Herbs have similar nutritional requirements to lettuce and can be grown right in the same system.

NFT herbs may be grown as a cut and re-grow crop. This is where approximately one third of the plant is harvested at any time and the crop grows new foliage for future cuttings. Most herb crops give several cuts before the plants need replacement. I have some of the most beautiful rosemary growing here in our hydroponic greenhouse. It has been thriving now for over 18 months and, like a fine wine, it seems to be getting better with age. Ask any good chef and they will tell you that fresh ingredients are the absolute best to work with. Why torture your taste buds any longer? Start growing your own delicious and nutritious hydroponic vegetables today.

Hydroponic growing is easy, clean and green. Almost any plant that can be grown conventionally can also be grown hydroponically. Hydroponic gardening takes up less space because you can grow right in your house, it uses up to 90% less water than soil growing due to the nutrient solution being constantly recycled, your plants are less susceptible to disease and best of all, getting started is surprisingly simple.

Sam Shroyer is has a bachelor’s degree in horticulture from South Dakota State University and 20 years of horticultural experience, it is his goal to “re-teach” the public that sustainability and self-sufficiency is well within everyone’s reach.

Subscribe to Garden & Greenhouse Magazine

Subscribe to Garden & Greenhouse Email Newsletter