Because hydroponics develops plants without soil, a hydroponic system frequently has a lot of moving parts: pumps, airstones, and the electricity to power them. But there are times when you just want to keep things simple. The Kratky technique shines in this situation.
It’s a method for growing hydroponically without the use of power, pumps, or wicks of any type. You don’t even need to add nutrients or modify your reservoir. It’s the closest thing we have ever seen to a truly “hands-off” growth method. Today we will discuss how to grow hydroponic Lettuce the Kratky way.
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Why grow Lettuce using the Kratky Hydroponics method
- Test after test has been done on the efficacy of various hydroponic builds, and Kratky consistently comes out on top in terms of crop yield. To prevent light from leaking through, choose a dark material.
- Setup is simple and inexpensive. Thanks to the idea’s adaptability. It may be created with items found around the house. Simply ensure that the seedling has plenty of room to establish roots.
- It’s as simple as it gets. You’re good to go as long as you get the nutrient solution right. You may wish to test the waters during the second week to make sure everything is in working order, but that is simply luck.
- Beginners will enjoy it. The Kratky approach will walk you through the fundamentals of a successful hydroponic setup.
- In comparison to other lettuce types, hydroponic lettuce grows faster. This is primarily due to the roots’ lack of need to expand out in search of nutrients in the soil. This is an added bonus, implying that you will generate money quickly.
- You won’t be spreading any soil-borne diseases onto your lettuce, which is a common problem for most gardeners.
- The lettuce can be grown in a bedroom, greenhouse, conservatory, rooftop, garage, window ledge, or corridor, among other places.
- With hydroponic lettuce, operating costs will be roughly 20% lower once the initial costs and installation have been paid for.
- Long-term lettuce yields can be achieved by spacing out your initial seed plantings by one week for a total of four weeks. Lettuce takes four weeks to mature.
- You won’t need to kill any soil-loving pests, which means you won’t have to spend money on pesticides. As a result, your lettuce will remain organic.
- Hydroponic lettuce is projected to grow 40 percent faster than soil-grown lettuce. This is due to the fact that you changed the growing conditions to make them lettuce-friendly. Lettuce will have access to all of the nutrients it requires as well.
Best varieties of lettuce to growing using Kratky method
Lettuces are often distinguished by the type of leaf they have or the shape of their heads. Depending on your preferences, these variants come in a variety of colors, sizes, and forms.
Mixes/blends of lettuce
These are a mix of several of the above kinds that are commonly obtained as pre-mixed seeds and cultivated in baby salad mixes with other leafy greens. This lettuce type is gaining popularity as a marketing variety for restaurant sales and farmers’ markets.
Whether it’s cos or Romaine, the choice is yours.
These lettuce cultivars are typically 8 to 12 inches tall and erect, with thick ribs and tightly folded, spoon-shaped leaves. The exterior leaves are typically deeper green, while the interior leaves are mellow to light green/white. Romaine lettuce types are grown for their baby leaves, which are used in salad mixes.
Bibb, Boston, or butterhead:
This is without question the most common greenhouse variety. Butterhead is a delicate cultivar with a soft, flowy, and ruffled green exterior and a creamy-colored to light green interior.
For the harvest, it’s almost entirely grown to full-head size.
Materials needed for growing Lettuce using Kratky Hydroponics method
- Tote: The capacity of the tote must be able to support a minimum of one gallon per plant. If you don’t have a tote with a raised lid, keep in mind that you’ll lose some volume between the lid and the net cups.
- Lettuce seeds: You can acquire these everywhere. They are relatively cheap, usually ranging from 1-3 thousand dollars for two or three dollars.
- A three-inch hole saw (and arbor): cuts the perfect size for utilizing the three-inch cups. Unless you obtain two-inch cups with wide lids, this isn’t necessarily true for the two-inch cup, and two-inch hole saw.
- Sponges: To contain the seed until it germinates and sprouts, grow sponges. Peat-based sponges, such as those sold by AeroGrow and Park Seed, or Rockwool can be used. To lower the pH of Rockwool, it must be pre-treated.
- Growing medium – You’ll need something with good aeration to anchor the plant. Hydroton clay pebbles or coco coir pieces work well.
- Nutrient medium: Nutrients can be found at your local hydroponics business or by searching online. Most, such as Maxibloom, Maxigrow, Dyna Grow, and others, will work perfectly. MasterBlend, MgSO4, and Ca(NO3)2. There’s more on that here.
- Grow light: Get daylight spectrum bulbs if possible. CFL and LED lights are also effective.
Steps to build the Kratky setup for growing Lettuce
Step 1: Using a hole saw, drill holes in the tote lid. Punch six holes in three shallow 10 gallon totes.
Step 2: Fill the net cup with grow media (clay pebbles, coco coir, etc.) and place the sponge inside. On the top of the sponge, place a little handful of seeds (3-5). It should have a little seed hole in the top.
Step 3: Fill the tote with a nutritional solution and place it somewhere it will stay. It should come up to a half-inch to an inch over the net cup’s bottom. To check the water level, put an empty net cup in there.
Step 4: Place the filled net cups in the lid with the top. What is the explanation for this? If you don’t use an airstone, this method ensures that they won’t dry out because your growing media is always wet.
As the plant grows, it will consume more water, lowering the water level – but by that time, your plant’s roots will have fallen into the nutritional solution.
“Aren’t air stones used for more than merely soaking the growing substrate in the seedling phase?” you might inquire. You’re right: this is where the Kratky Method’s beauty begins to shine.
As you are not refilling your reservoir, so your plants will continue to use water and expose more of the roots to the air, ensuring that they receive enough oxygen to survive and thrive.
Challenges of growing Lettuce using Kratky hydroponics
If you’re considering employing Kratky on a commercial scale, bear the following in mind:
1. Variables are more difficult to regulate.
Before you fill a tank with your source water, ensure the pH and nutrition solution is correct. Not doing this will make you test each tank’s EC and pH separately and then adjust each tank separately. This is a significant amount of work!
2. Difficult to control the temperature
Because the water is stationary, it can be more difficult to control the temperature. If you’re using a passive greenhouse, use caution with this strategy because your plants may not tolerate significant temperature variations at night.
3. As it grows in size, it gets less efficient in terms of time.
Cleaning out 20 tanks every few months isn’t too difficult, but cleaning out 100 tanks is a waste of time till you rent it out.
4. There will be minor annoyances and irregularities.
An inconsistent plant will grow if the ground underneath is not level or the plastic liner is not installed properly. The beginning point of the water level in respect to the raft will be unequal if the land is uneven.
If one end is too shallow, the roots may not be fully immersed in the water, resulting in a dead seedling a few days later. On the other hand, if you go too high on the other end, you’ll notice more bottom rotten leaves because the young transplant was likely oversaturated.
5. In a passive design, there will be some surprises.
Numerous frogs, grasshoppers, crickets, and spiders are attracted to the raft area in a passive greenhouse design that works well for Kratky. Nature finds its way in since the rafts are low to the ground and have open sidewalls.
This might be viewed as a positive because they are a sort of natural pest control, but they can also be frightening when they appear unexpectedly.
6. Quality raft material and a covering are required.
To protect your system from the elements, you’ll need a greenhouse or some other type of covering. But you’ll also need to keep rainwater out of the tanks.
You risk drowning your plants if the water level rises too high during the growth cycle. In terms of raft material, 3/4′′ thick foam board is the most cost-effective and long-lasting option.
Some Tips to remember while growing Lettuce the Kratky way
- Aluminum Foil (or some other covering) is required. The problem is that exposing the roots to light encourages the growth of algae, which can “steal” nutrients from your liquid plant food. You want all of that goodness to aid in the growth of your plant, not the algae.
- Make Sure the Lid Is Tight – You’ve worked hard to ensure that the water within the container is ideal for your new crop. Wouldn’t it be a shame if it rained and all that dirty water got inside your container? Or if a bug got inside and caused havoc on your delicate root system.
- You only have one chance to get it right, so do it right the first time. If you don’t get the pH right the first time and don’t check on the system subsequently, you may be dooming your plant from the start.
- Because individual testing is necessary, large-scale production can be tedious. At bigger sizes, testing the water for each container becomes inefficient. While some farmers have been successful in making larger systems economical, the majority choose to use electric systems for greater control.
Is Kratky the perfect choice for your Lettuce?
The Kratky method works well for you if you want to grow a lot more than you need quickly and effortlessly. If you want to sell a huge quantity of a few specific items to restaurants and grocery shops, this may not be the best option.
Overall, The Kratky approach is to new people who are interested in gardening. It’s quite basic, yet it can be extremely rewarding for someone who is just getting started. If you enjoy this, you’ll love learning everything else there is to know.
