Aquaponics systems commonly involve raising freshwater fish because they can tolerate diverse water temperatures and pH…
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The decision to grow lettuce in aquaponics gardens has become a go-to and a cornerstone vegetable for both new and veteran gardeners alike. Available in a vast range of varieties, this staple ingredient of salads everywhere tends to have lower nutrient requirements than other plants and is therefore perfect for beginners or those with gardens that are just getting established.
In this article, we’ll take a look at the best way to grow lettuce in aquaponics gardens, specific care instructions, and how you can protect your treasured leaves from common pests and problems.
Why Grow Lettuce in your Aquaponics Garden?
If you are looking to grow a vegetable that offers plenty of variety and quick results, lettuce is a great choice. From crisp and juicy iceberg lettuce to succulent and slightly bitter Romaine, you can choose to plant one variety or several at the same time. Lettuce matures quite rapidly, and you can expect to see great results in an average of 40 days. There is something very satisfying about preparing a salad with the lettuce you grew yourself, and in just over a month, you could be doing just that.
Planting Your Lettuce Using a Raft System
For plants like lettuce, leafy greens, or herbs, a floating raft style bed is the best option. You can use a specially-made raft system or simply use a sheet of Styrofoam cut to about one inch in thickness. The raft should be able to float freely on top of the water while still allowing enough room for your filter tubes, feeding fish, etc. The typical size of aquaponics pots is 2 inches, so you would need to cut out holes large enough to accommodate your pots. An excellent way to do this is simply to draw around a pot directly on the Styrofoam and use that as your cutting guide.
You can choose to grow your lettuce from seeds or by using seedlings with roots. If you decide to use seeds, you will need to use a seed-starting medium, such as Rockwool or oasis cubes.
Ensuring the Correct pH Values
To ensure a successful crop, you need to start with the right pH level and maintain it throughout the growing process. pH testing kits are invaluable and should be an essential part of your aquaponics setup. These can cost as little as five dollars and can be found in most pool, pet, and hardware stores. The optimal pH for growing lettuce is between 6.0 and 6.2.
Lighting Levels and Temperature
Lettuce requires up to 18 hours of sunlight every day. If you can, position your system next to a sunny window. While this won’t give sufficient light all day, you could supplement natural daylight with some artificial grow lights that come on at sunset and switch off a few hours later.
When it comes to setting the right temperature, lettuce thrives in air temperatures above 60 degrees and below 75 degrees Fahrenheit. You should also aim to keep the water temperature at around 70 degrees Fahrenheit.
Ensuring the Right Level of Nutrients
With the right aquaponics setup, you may not need to add any nutrients to your system for lettuce cultivation. However, there are times when lettuce may need additional nutrients that your fish cannot supply. Calcium is one such nutrient. This can be applied directly to the leaves and has no adverse impact on the fish.
Protecting Your Lettuce From Pests
The last thing you want after investing so much time and effort into your lettuce is to find that it has been ravaged by insects or decimated by disease. You will need to choose pesticides that are not harmful to your fish or the plants themselves and apply these exactly as instructed by the manufacturer.
Get Started on Your Lettuce Aquaponics Cultivation Today
Lettuce is one of the easiest vegetables to grow in an aquaponic garden and one of the fastest. When you have the right conditions in place, there is no reason why you shouldn’t be enjoying delicious, crisp, and versatile salad leaves in a matter of weeks.