Grow lettuce and radish hydropinically at home with Mars Hydro Hydroline12

Lettuce and Cherry Belle radishes are popular vegetables on the family table. While it has been almost a year since the release of Mars Hydroline 12, and growing lettuce and growing radishes hydroponically are effective and easy, here is a step-by-step guide on how to grow lettuce and Cherry Belle radishes using the Hydroline12 hydroponic gardening kit.

What To Prepare Before You Get Started?

Growing hydroponically is easy, all you need is a Mars Hydroline12 hydroponic kit, seeds (lettuce or Radish Cherry Belle), nutrient solution, a TDS meter, a paper towel, and perlite.

The equipmnet you need to grow lettuce and cherry belle radish at home hydroponically

Perlite is not a necessary part of the growing process in lettuce grow, but it will be of great help when growing radishes.

Seed Treatment

The seeds have been carefully stored to prevent them from germinating on their own. So when you open the seed bag, seeds not knowing what’s happening will insist that it's not the right condition for them to grow and continue to sleep until they die from being drowned by your hydroponics. Therefore, the first and foremost thing to do before you put the seeds into the machine is to "wake up" the seeds.

To “wake up” the lettuce seeds, soak the seeds in hot water at 40 to 45 ℃ for 20 minutes, or in ordinary water for 6 - 8 hours.

To “wake up” the Cherry Belle Radish seeds, soak the seeds in ordinary water for 2 - 3 hours.

The handling of seeds: soak seeds and paper towel germination

Paper Towel Method For Germination

After the seeds are wakened up, there are two ways to go. One is that you put the seeds into the sponges on the Hydroline12 and start growing immediately, but it’s not effective. Some seeds may have become bad seeds after long-timer storage and won’t grow again. That’s why a manual germination operation is needed.

The Paper Towel Method is a simple but effective way to germinate. You cover the seeds with a moistened paper towel and in a day or two the seedlings will break out of their shells and feel the world. The temperature for lettuce to sprout is 15-20℃, while it’s 20-25 ℃for the Cherry Belle Radish. Some species or plants in lower temperatures may take a longer time to sprout, so for the complete guide to Paper Towel Method, clickhere. Besides, in some regions where it's too cold in winter, you may need to grab a seedling heat mat to make sure your germination temperature is suitable.

One thing you need to pay attention to is that it’s essential to wash the possible mucus on seeds due to soaking with water before you use the paper towel for germinating your seeds. This mucus can make the seeds susceptible to mold during germination, leading to rotten seeds.

It is possible not to germinate and directly put the wakened seeds into the Hydroline12? No problem! You can just throw one good seed into each sponge, and just let them grow!

You need to be sure that every seed you bought is a good seed. However, you will still come across troubles such as uneven emergence or seeds sown that don't come out. In this case, you must put 2-4 seeds into one sponge to ensure that at least one seed is alive and grow well! However, more troubles arise. It may happen that one sponge has two or more seedlings alive and it becomes so narrow for them to grow that you need to thin the seedlings into different sponges. So, to avoid these troubles and achieve more success, doing a simple Paper Towel Germination and pick up even seedlings to grow!


Preparation Of Hydroponic Solutions

Any organic-based houseplant fertilizer (nutrients) is good enough to be a hydroponic solution. If you don’t know which one to go for, please click here.

Since the nutrient solution has instructions on how to use it to mix the perfect horticultural nutrients for lettuce grow or radish grow, what we need to do is to adjust the EC value of the solution. 

For growing lettuce and Cherry Belle Radish hydroponically, the EC value should be 1.0-1.5 ms/cm (1000 - 1500 μs/cm). 

All you need to do is to mix the nutrient solution according to the instructions and add water until the TDS meter reading reaches this range.


Grow Lettuce & Radish Cherry Belle With Hydroline12

After the above things are prepared, let’s start growing at home.

Sow Seeds

Take out the sponges from the Hydroline12 hydroponic kit and place the planting sponges into the water to allow them to fully absorb water. Hydroline12 comes with  12 sponges, which means you can grow 12 plants at the same time.

Sow seeds (sprout seedlings) in each plant hole on the sponges. The sponge is placed in the planting basket, which is then placed in the Hydroline12 and finally covered with a planting dome to create a mini greenhouse where the seedlings can thrive.

When planting Cherry Belle radish, you can cover the top of the seeds with a grain of perlite to help with the upcoming growth phase. Perlite will provide small pressure to the fast-growing seedlings so as to keep the stems grow down into the sponges and not grow out of sponges and make the seedlings grow stronger. (When growing in hydroponics, the seedlings grow very fast!) 

Two ways to sow seeds in the sponges

It’s an optional operation that you can do to make your radish grow better, but if you don’t want to, it does not matter. But it's possible that the stems of seedlings will come out of the sponge and you need to cut the sponges in half and put the stems inside the sponges so that the seedlings can absorb the nutrients.

Hydroline12 Settings

The Mars Hydro Hydroline12 hydroponic gardening kit comes with a lighting source and various setting options such as 2 growing modes, 4 timers, and 5 dimming levels. It offers growers plenty of options for better and more precise cultivation, on the other hand, it makes it more difficult to choose the right settings.

To grow lettuce and Cherry Belle radish, set the Hydroline12 to the following settings:

  • Vegetable Mode
  • The lowest-height light post
  • The highest light intensity
  • 12 hours ON light schedule

The settings of Mars Hydro Hydroline12 hydroponic gardening led kit to grow lettuce and radish

Lighting intensity may be too strong for some varieties of lettuce or Cherry Belle radish due to differences in variety. Keep a close eye on the foliage and raise the light post an additional 5 inches once you notice burnt leaves to ensure proper growth.

Seedling Stage

Once a small leaf emerges, it means the seedling stage has started. And you can remove the growth domes to expose the seedlings to the air. Don't wait until the young seedlings have grown to the dome before doing so.

remove the grow domes when small leaf emerges

The seedling stage for both lettuce and Cherry Belle radish lasts for around 10 days. Lettuce prefers cooler temperatures; if it is left at higher temperatures, it will grow stems only, become bitter, spike, and bloom early. 

Therefore, the ambient temperature (or environment temperature) at this stage should be maintained between 18°C and 23°C.

Pay attention to changes in the concentration of the nutrient solution, preferably changing it once every 7-10 days.

Vegetative Stage

After around 10 days of seedling growth, both lettuce and Cherry Belle radish will enter the biomass accumulation phase - the vegetative stage. 

Vegetative stage of lettuce

At this stage, raise the EC value of your nutrient solution to the range of 1.5 -1.8 ms/cm (1500 - 1800 μs/cm), and change it every 7-10 days.

The lettuce needs 10 - 20 days of accumulation in the vegetative stage, and the Cherry Belle radish takes 20 - 25 days.

When growing lettuce, keep checking roots and leaves every 3-5 days to avoid bad or weak roots and to trim yellow leaves as these may lead to unproductive growth.

When the radish expands, it can be plucked to the outside of the planting hole, keeping only part of the root beard inside the sponge, which contributes to the expansion of its fruiting part.

Pluck out the radish to make it grow bigger

Harvest Of Lettuce and Cherry Belle Radish

You can expect harvests after vegetative growth. 

It takes a total of 20-30 days after you sow the seeds for the lettuce to be ready to harvest the leaves of lettuce, or 30-45 days if you want to harvest the entire lettuce. And if you don’t want to harvest it at present, be sure to shorten the lighting period from 12 hours a day to 8 hours a day. By decreasing the lighting time, the lettuce grows more slowly so that you won’t receive lettuce with poor taste later on.

Cherry Belle radishes, on the other hand, will take 30-35 days to be ready for harvest.


Tips To Grow Lettuce & Cherry Belle Using Hydroponics

  • There are times when young seedlings grow only the stems and not the leaves. The reason may be that the ambient temperature is too high or the light intensity is low. First, make sure your temperature is in the range of 18℃-23℃; second, if your temperature is optimal, increase the light intensity to the highest level.
  • The Seed Soaking Time and Germination Time:

Plant Type

Soak Seed in

Soaking Time

Germination Temperature

Germination Time

Lettuce 1

40-45℃ water

20 m


1-2 d

Lettuce 2


6-8 h


1-2 d

Cherry Belle


2-3 h


1-2 d

Wash the seeds completely after soaking.


  • Pay attention to changes in the concentration of the nutrient solution, and preferably change it once every 7-10 days.

Hydroponic Solution’s EC Value For Lettuce & Cherry Belle Radish

Seedling Stage

1.0-1.5 ms/cm (1000 - 1500 μs/cm)

Vegetative Stage

1.5-1.8 ms/cm (1500 - 1800 μs/cm)


  • The Settings of the Mars Hydro Hydroline12 Hydroponic Growing Kit throughout the entire growth of lettuce and Cherry Belle radish

Light Mode

Vegetable Mode

Light Post Height

The Lowest (11’’)

Light Intensity

The Highest

Lighting Period

12 H


Be sure to keep an eye on the root condition and leaf condition of your plants. If things like burnt or weak roots happen, instead of decreasing the light intensity, raise the light post height 5’’ more first.


To Round Up

The harvest of lettuce grow and radish grow using Hydroline12

Growing at home using hydroponics is easy and clean and 20% faster than growing with soil. And the Mars Hydro Hydroline12 makes it more convenient to grow not only lettuce and Cherry Belle radish but also other vegetables like tomatoes, peppers, basil, etc., It’s also capable of growing houseplants, and clones for medical plants.

Live an organic life and eat healthier with Mars Hydro, with Hydroline12.