Aquaponic systems are known particularly for their quick and efficient plant growth without the use of soil. Cucumbers are one of these plants that seem to take advantage of this type of system.
Cucumbers can grow very well in aquaponic systems mainly because they are green leafy plants that thrive in an environment with lots of nitrogen nutrients. These nutrients are known as nitrates and are abundant in aquaponic systems.
Growing cucumbers is not such a hard feat. Simply place the seed in fertile soil or a seedling in an aquaponic system and it grows regardless. The aquaponic system, however, has an advantage to growing cucumbers which we will discuss in this article.
See our complete guide on aquaponics and what you need to know to run a successful system.
So how do you grow cucumbers in an aquaponic system?
Cucumbers are vines plants where vines can reach a distance of over twenty feet in some instances.
The plant can be bought as seedlings from the agro shop or grown in your own germination tray from dried seeds.
Either way, once the seedling is about 2 – 3 inches high with at least two leaves, they can be removed and replanted in the aquaponic system.
Replanting Cucumber Seedlings.
- Gently remove seedling from planting tray
- If dirt is used; remove the dirt gently without damaging the roots
- If using netcups; open support medium (usually rock wool) and place plant at the center of the rock wool.
- Place the rock wool in netcup ( 2? or greater)
- Place in the aquaponic system. ( either nft or dwc)
After a few days :
The fruit is sprouted firstly as a bud then into a flower which is pollinated by insects. The pollinated flower then forms into a small cucumber which grows until it?s ready to be harvested.
Once cucumbers Start to grow they can grow very wild so it can be worthwhile providing some type of support on which the vines grow. What I have found is that allowing the vine to grow above on a net or mesh system allows for an easy harvest of the fruit when it?s ready.
You don?t want to let the vines grow into the ground because insects and other pests can easily access and destroy the plant and fruit.
The root system in cucumbers is just as wild as the vines and can grow very long. The problem with this is that the roots ten to grow and plug plumbing fitting in the aquaponic system causes water to back up and overflow leading to water and nutrient loss.
So it is a good idea to keep this in mind when planting them in aquaponic systems.
I also found that growing them in an nft, modified nft (nutrient film technique) and DWC (deep waters culture) system, produces more plants in a smaller space.
Cucumbers can also grow in grow beds. So whichever system you make have these plants can adapt and make the best of their medium.
Why do cucumbers grow so well in aquaponics?
Cucumbers grow very well in aquaponics systems mainly because they are green and leafy water-loving plants.
Being green and leafy shouts out Nitrogen in the agriculture world. Nitrogen is available to plants in the form of nitrates in nature and aquaponics.
Nitrogen is an important component of chlorophyll, the compound by which plants use sunlight energy to produce sugars from water and carbon dioxide. This process is also known as photosynthesis.
In aquaponics nitrates are abundant under the right conditions.
Nitrates are produced by the process of nitrification. In this process, the ammonia found in the fish’s waste is converted into nitrite and then into nitrate by the friendly Nitrosomonas and Nitrobacter bacteria.
If it wasn?t for this process the nitrates would not be available in aquaponics systems, which is why farmers always ensure that the water conditions are right for the bacteria to do their work.
Cucumbers just reap the benefits from the nitrification process and bask in the abundance of nitrates available in the system. Which is why they grow so well.
What can cause cucumbers to fail in aquaponics?
As discussed, cucumbers love nitrates. If the nitrate concentration in the aquaponic system drops the plant growth and yield will also drop.
But what can cause nutrient levels to drop?
Aquaponic cucumbers require certain contains for optimal growth. The Temperature, pH, and sunlight conditions the plant are exposed to determine how well cucumbers grow in the system.
Temperature directly affects the pH of the water. The higher the temperature gets the more acidic the water becomes. This is because it?s easier for the water molecules to dissociate into hydrogen ions as water temperature increases.
Acidic conditions reduce the availability of nutrients for plants in aquaponic systems.
The pH scale measures how acidic or alkaline something is.
pH is measured in a range between 1.0 to 14.0
1.0 being the most acidic, 7.0 is neutral and 14.0 is the most alkaline.
Maintaining a slightly acidic condition between 6.0 to 7.0 is necessary for cucumbers plants to grow well.
Sunlight is necessary for all plant growth and for cucumbers it?s no different. Cucumber plants require full sunlight for them to reach their full bearing potential.
A lack of sunlight would cause reduced growth and fruit production.
Pest also plays a part in how well a crop produces in aquaponics. Aphids and leaf miners once allowed to multiply can wreak havoc on a healthy growing cucumber plant and this should be prevented to maintain healthy plants.
As far as pests go, my last cucumber crop came up well until the third week. There was no insects but the leaves were disappearing. I was baffled because everything was going so well and the scary thing is that there was no leaves on the ground.
It turn out that there was an iguana making a feast out of the lush green leaves and had me confused for days.
This is another type of pest to consider depending on your region.
The control of pests can ultimately make or break the growth and fruit production of any plant in an aquaponic system.
See our post on controlling pests in aquaponics.
When to harvest cucumbers?
Fruits are ready for harvesting between two to three weeks of transplanting.
Don?t allow to get too full in size. These tend to lose taste as they overly absorb water.
Cucumber plants tend to produce between ten to twenty cucumbers per plant. This can give you an average of how much yield you may achieve for the amount of seedlings you have planted.