How does Aquaponics compare with Soil Gardening?

Although we do produce both Permaculture and Aquaponics videos we were asked recently to compare the two methods and which one we preferred using ourselves – in our garden? Notice the caveat – in our garden! Its a difficult question to answer as each method has its strengths and weaknesses. There are some things that grow best in soil like potatoes, pumpkin and other root vegetables like carrots that perform very well in a humus rich no dig well mulched and manured soil garden.

Jade Perch rising to take some fish food

Then there are other things that are particularly well suited for aquaponics. Its just a matter of picking the right method that works best for you. We live close to the sea so our soil is mostly white silica sand. There is hardly any nutrients and whatever nutrients we do add tends to leach away very quickly. Imagine growing something on a sand dune? We do have a vegetable garden where we grow mainly root crops like potatoes in a no dig garden that has plenty of straw and horse manure applied. It works quite well until the chickens jump over the fence and start digging everything up. But watering it in the summer months is a nuisance as the warm winds tend to dry things out very quickly.

Pak Choi in the Soil garden compared to a similar seedling in Aquaponics

When we first installed our aquaponics system we had a lot of seedlings left over that we also put in the soil garden and as an experiment watched how the two systems compared as the weeks rolled on.
This was in the summer months and pests like grasshoppers were at their peak. The Pak Choi in the Aquaponics system was identical in size and shape to the seedling we also planted in the soil garden. The Pak Choi in the aquaponics system performed best as you can see from the photos. It didn’t seem to get attacked by pests and looked a darker richer green colour.

Aquaponic cucumber compared with store bought item

I wouldn’t say these tests are conclusive by any means or indeed scientific. The plants in the soil garden were planted at ground level where insects would have an easier target. The plants in the aquaponics system were planted at waist level and maybe out of reach of some insects. The aquaponics plants are not stressed due to the fact that they have a constant stream of nutrients at their disposal. Their roots are always moist.

Not so the soil plant. Although it was mulched, soil conditions can dry out stressing the plant somewhat. But both plants were in a sunny position and only a short distance from one another. The plant in the aquaponics system grew very well. The stalks snapped with a rich crunchy sound and made an excellent stir-fry. We couldn’t use the plant from the soil garden because of the condition it was in and it was eventually discarded. So much for the test.

Soil Gardens where we live constantly produces vegetables with ease when conditions are ripe and with little energy overheads. Aquaponics is a mechanical system and prone to failure if plumbing and pumps break down. But having said that, for growing salad vegetables like tomatoes and greens – we cannot compare how well an aquaponics system performs and our tomatoes will keep producing ripe fruit for over six months at a stretch. For a small family who need fresh green salads picked right before the evening meal – its a no brainer. Aquaponics rules!